Chrysler 68RFE Transmission • Problems and Solutions (2023)

Introduction to 68RFE Transmission:

As the leading choice for high quality, proprietary 68RFE transmissions, conversion kits and parts, we are often bombarded with questions about their myriad problems and how to avoid them. As a result, it became clear that this popular and often problematic transmission needed its own installation in our Drivetrain 101 Education Section.

Are you ready to become an expert on the "infamous" 68RFE transmission? The Chrysler 68RFE transmission has been a step forward and a bane for the Cummins 6.7L community since 2007.5 when it became the successor to the heavily supported system48RE transmission.

The 48RE was based on the 727 TorqueFlite from the '60s and '70s, making it a reliable commodity; despite its unique imperfections. To become an expert on 47RE or 48RE,Check out our 101 shows on 47RE and 48RE here.

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Our goal is to ensure that you, the reader, are as informed as possible about the 68RFE transmission and your individual needs. Whether you're into daily driving or drag racing, if you're interested in learning more about the 68RFE transmission, this Drivetrain 101 is for you!

Neste Drivetrain 101, we will address the following:

- The most popular crashes we've seen on 68RFE broadcast

- Its functions related to TCM tuning and shift/lock protocol modification

- The strengths (believe it or not, there are quite a few!) of this stream

-Resources for relevant updates and upgrades

And a lot more!

Product features of the Chrysler 68RFE transmission:

-68Transmissões RFE
-68RFE torque converter
-68RFE conversion kits
-68RFE valve body
-68RFE-For you

Popular sources of information about shipments:-Top 5 benefits of an upgraded or built gearbox
-Why is the torque multiplication factor calculation so important?
-Top 5 ways to extend the life of a factory transmission

A brief history of the 68RFE transmission:

The 68RFE transmission came out at a time when the Ford 5R110 was in the midst of turning and the 6R140 was just an idea gaining momentum. At the General Motors end, the 6-speed Allison was in service and the LMM DuraMax had just emerged as the more emission-friendly LBZ. This meant Dodge played as usual to catch up with its outdated and inferior powertrain technology.

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Roughly speaking, the 68RFE transmission arrived in 2007.5, controlled by a standalone TCM mounted on the passenger side of the truck's firewall. This lasted until model year 2010, when not only the body style of the "4. Generation”, but also an all-in-one PCM system that obviated the need for a standalone control module for the transmission. The following year, 2011, it became apparent that the material used to manufacture the pumps and valve bodies (an extremely soft aluminum) was deteriorating rapidly, contributing to an excess of warranty claims for Mopar.

Of course, Mopar heard the news of warranty calls and took action to make a product that was marginally cheaper (let's be honest here) and anodized the casting itself to avoid the complications of bore wear over time. In fact, we have an entire Transmissions 101 dedicated to this particular topic. It can be seen here:

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This had an advantage, it partially minimized cross leakage. That's all. We've tried and tested anodized and non-anodized valve bodies and the conclusion is consistent and simple.In the factory configuration, anodized valve bodies appear to have the same problems as non-anodized valve bodies. They just seem to wear out more slowly.


Luckily, they tried to address the complications that plagued the 68RFE transmission in 2019. Unfortunately, they didn't properly address the issue. They have completely redesigned the pump and valve body to provide the torque converter lock-up clutch with reliable construction and precise control. All of this in good faith, but it doesn't address the most productive issues in this show, as we'll discuss below.

How the 68RFE Transmission Clutch Packs Work:

Each transmission has unique qualities in how it calculates shifting behavior, how it responds to solenoid inputs, and more. The 68RFE transmission is no different. Something that is critical to understanding the 68RFE transmission is understanding the clutch application chart. To do this we need to analyze the following information:

Reverse - Down/Reverse + Reverse

1st gear - slow/reverse + underdrive

2nd gear - 2nd clutch + underdrive

3rd gear - 4th clutch + underdrive

4ª Marcha - Overdrive + Underdrive

5. Gang - Overdrive + 4. Kupplung

6. Gang - Overdrive + 2. Kupplung

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This is a very common configuration for a 6 speed automatic transmission with dual overdrive torque converter. As you can see each gear consists of 2 clutch packs. This is because clutch packs are not assigned to specific gears (1, 2, 3, etc.), but to different transmission functions; often including hubs, baskets and the like. In most transmissions, a combination of planetary assemblies/clutch packs must be activated together to produce the desired input shaft to output shaft speed ratio.

To generate an arbitrary example that might make this more understandable, imagine losing 4th, 5th, and 6th gear. Based on the above data, it is clear that the overdrive clutch pack is the designated clutch pack based on the gears being driven and the clutch packs engaged in those different gears. If overdrive is only used on 3 gears and all 3 gears are not accessible then the likelihood is overdrive failure.

This diagnostic logic can be applied to virtually any transmission. The overdrive clutch pack is an exceptionally large failure point on these transmissions and that's why we pioneered our innovation68RFE Cherry Bomb.This would include the overdrive, underdrive and reverse sections of the input clutch drum to correct said error.

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68RFE Transmission TCM Tuning and Adaptability Protocol:

As previously mentioned, the 68RFE transmission attempted to make a direct (and miscalculated) turn in the Allison/TorqShift market. This transmission had to be electronically advanced and able to think for itself. Compare this to Tesla cars being able to drive themselves and other automakers trying to keep up with the technology. Allison has been at the forefront of adaptive shift technology from the start, and it was Mopar that eventually came on board.

The point is simple, the 68RFE transmission wasn't advanced enough in its logic to make really good decisions about shift timing and driving dynamics. As a result, the show suffers from constant confusion. Does he want to lock or unlock the torque converter? Which gear does he want? How much line pressure does he want now? The only solution to these extremely sporadic variables is TCM tuning.

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There are numerous aftermarket products that act as "plug and play boxes" and artificially increase the line pressure. We have gone to great lengths to understand how all of these products work and we have found that they all work very similarly. They are assemblies of resistors and logic gates used to "fake" transmission into certain behavior patterns.

*Pro-Dica*- Are you looking for a safe way to plug internal leaks and allow higher line pressure in clutch packs? One of the smartest and easiest transmission upgrades for the 66RFE transmission is a valve body. Consider airtight, ultra-fast shiftingNext generation valve bodies here🇧🇷 a very significant improvement.

These devices arenoa safe method of increasing line pressure and should be avoided. The best tuning rigs (and we don't get a dime to say so) in our opinion are EFI Live and EZ Lynk for the 6.7-liter Cummins. Both prove to be excellent systems for implementing high-quality TCM tuning under the guidance of a qualified tuning professional.

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-Yrepresents the commanded line pressure based on the calculations to the right of the equals sign.

-Mrepresents gain, a variable used to correlate engine load to rail pressure requirements. Tuners adjust this value to increase line pressure.

(Video) 68rfe problems

-xrepresents engine load, a factor used by on-board computers to process and understand the resistance exerted on engine torque.

-Brepresents a baseline of minimum line pressures that must be commanded in each forward gear.

When we talk about the TCM fit and adjustability protocol, it's important that we talk about clutch volume indices, also known colloquially as “CVIs”. CVIs are a rational time metric for applying piston travel distance. This unit of information is used to understand the remaining three-dimensional volume of the clutch based on the engagement times of the clutches at the moment their respective solenoid was energized and the circuit was closed; returns an electrical continuity signal to the onboard TCM.

The TCM then uses both binary and Boolean logic to evaluate which solenoids are on and off and what logical decisions the onboard computers controlling the transmission will make. In simpler terms, the longer the clutches take to engage, the less friction there is left in the clutches themselves, according to the 68RFE transmission control module. Based on this information, the transmission will retard or advance the solenoid timing accordingly to improve shift response. Below is a list of the average CVI ranges as mandated by the Automatic Transmission Rebuilder's Association:

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Putting all this information together should give you a much better idea of ​​how the 68RFE transmission brain works. It's all too common for transmission specialists to sue the mechanical and hydraulic side of the trade and pay little attention to the electronics that turn them fully on. We will now continuously, in no particular order, cover the critical components of the 68RFE transmission and their problems, fixes, and upgrades. As we provide additional reading on each of these components, we will answer these 3 questions for each critical component:

- WHY does it break?

- HOW do I prevent it from breaking?

- WHAT can I use to make it stronger?

Problem #1 - The torque converter

The torque converter of the 68RFE transmission is actually very efficient in some respects. It has a huge stator (the most powerful of the Big 3, believe it or not!) and a double-sided friction element, shaft. This makes it a viable factory-form competitor in head-to-head competition.

Unfortunately, it has numerous diseases. It can't handle the power of a tuned truck, even at its smoothest tune. It might survive, but it's temporary and the physics are against you. The stator spring itself is prone to failure, as is common on some Dodge converters. This is caused by your lower oil seal which can be upgraded to an aftermarket torque converter like ours.68RFE Project Carbon™ triple disc torque converter.

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These torque converters also have unnecessarily high stall speeds. This is evidence of Mopar's emissions compliance and is not based on any practical or functional reason. The solution here is to minimize friction within the torque converter by opening up the ribs on the stator itself. This slows the stall speed, allowing the torque to reach the ground safely and efficiently. Many people describe this as a feeling of "empowerment," but it's actually an illusion. The truck simply replaces lost torque that didn't make it to the bottom in the factory torque converter, which is plentiful and parasitic.

Problem #2 - The high pressure oil pump

The 68RFE transmission has a very unique pump design with 3 pump gears instead of the standard 2. This should help the 68RFE generate line pressure quickly, reliably and efficiently. The good thing about this design is that it's really fast and efficient!

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However, the problem is reliability. This pump empties its bores very quickly and starts to leak just like the valve body. There are many reasons for a pump failure, but we will cover the bigger points as follows:

- The center pump gear wears out badly and causes oil reversal problems.

- There is a little known pump drain circuit that needs to be closed to permanently eliminate this issue.

- The pump's internal valve train needs a complete overhaul for longevity. The valves are heavily made of magnesium (Mg) and nickel (Ni), two elements that are fierce when held in an aluminum (Al) port.

- The accumulator piston for the TCC has a tendency to fall against its support during converter clutch actuation. This can be fixed by recalibrating the pump accumulation system with different hardware.

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Another understandable data point is that the 68RFE transmission oil pump acts as the torque converter valve body. They go hand in hand, and when one fails, the other usually fails. Our68RFEProject Carbon™ High Pressure Oil PumpIt combines all of these critical modifications into one and is a good platform for gear designs where there are doubts about the integrity or performance of an OEM pump.

Problem #3 - The input shaft

(Video) 68RFE Transmission Teardown inspection - Spanish - Transmission Repair

The input shaft of the 68RFE transmission is a very simple part of the equation. It is responsible for collecting and delivering all the power that comes out of the torque converter68RFE input clutch hub.The point here is pretty easy to guess, the factory input shaft was never made for aggressive use. In fact, it was hardly made for factory use. The 68RFE transmission input shaft is an inflated version of the 545RFE input shaft. In fact, we've attached a photo of a billet 545RFE input shaft below, does it look familiar?

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The 68RFE transmission's input shaft is instantly undermined in power and performance, just as it is undermined by drag and the powerful locking action of a billet three-plate torque converter. It is made of alloy mild steel with low stress and huge yield. The OEM input shaft is not necessarily lossless, it is very safe to use at modest power levels. It's even standard on some of our simplest transmissions, like oursXtreme Tow™68RFE Transmission🇧🇷 Thing is, once you start raising high expectations, the factory axle just isn't good enough.

The next logical step is a300M billet 68RFE transmission input shaft.This becomes necessary for anyone planning to increase launch, heavy tow, add significant amounts of power, or simply invest in safety and longevity. We see these input shafts reliably surviving up to around 900hp, but we've seen several success stories at higher numbers. For everyone over 850hp we recommend theMaraging steel 68RFE input shaft.

Problem #4 - The input clutch drum

The input clutch drum on 68RFE transmissions is a complex composite component with many different purposes. In fact, all gears use at least one of the clutches in the drum. The input drum of the 68RFE transmission consists of (front to back) reverse, overdrive and underdrive. It is basically built around a large reluctance wheel that communicates with the input shaft speed sensor. This reluctance wheel is known as the "input clutch hub" and is often replaced with a spline in heavy-duty applications. Below is a photo of a 68RFE billet inlet clutch hub.

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This drum has several diseases. The first is that it flexes outward due to a physical force known as "centrifugal inertia". This is the same force that allows you to spin in circles while swinging a bucket full of water, and the water will stay in the bucket as long as you spin fast enough. This is solved in a number of ways, but the most popular is the patented Overdrive/Reverse PistonTambor Sonnax 68RFE Smart-Tech.

It also lacks the clutch volume needed to securely engage the overdrive clutch pack. The 68RFE transmission's overdrive clutch pack consists of .051 inch thick clutches (no kidding, they really are that thin) stuck in a hot, malfunctioning, severely restricting drum. While there is too much data to reasonably include in this article, it is safe to say that every 68RFE transmission we make has a completely redesigned overdrive section. This is widely considered to be this transmission's biggest Achilles' heel and we do not offer a stock overdrive stack on any of our transmissionsbuilt 68RFE transmission.

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A final and equally valid affliction for the 68RFE transmission's input clutch drum is the overdrive hub. The overdrive hub (pictured above) is the splined part that the overdrive clutches sit on. During 3-4 upshifts, this hub is speed synchronized to the input shaft against the truck's ground. The problem with this is that just like an input shaft, it will microfracture and fail. If you're doing the 3-4 gear change with the torque converter lock-up assembly engaged (as tuners often do), you're putting incredible stress on that particular component. As a result one68RFE overdrive hub for extreme useshould always be used for proper applications.

Problem #5 – The Support Center

 The center support of the 68RFE transmission is unique. Each gear (except low gears) with overdrive OR underdrive must use at least one of the two clutch packs in the center bracket. The center bracket houses the 2nd and 4th clutches and is located just behind the input clutch drum assembly. It should be noted that these 2 clutches correspond directly to planetary arrangements that conflict with each other in the final gear ratio. As a result, these claws cannot be applied without forcing the person to "win". These clutches should never attempt to engage simultaneously.

These clutches rarely fail, but when they do, it's usually the cause of a valve body leak (as discussed later in this post) or the culprit of the huge power increase. Luckily we have both covered in ours68RFE Transmission Conversion Kitsand other complete transfers. While there are many ways to solve this problem, adding clutches to the center member assembly is a surefire way to increase torque capacity.

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These center brackets are also prone to failing or excessive wear on the inside, sometimes necessitating a complete replacement. For more information about our center's support, visit our68RFE Project Carbon™ Center Support Kit.Steel billet options are available for customers looking for extra high performance alternatives.

Problem #6 – The low/reverse drum

 Fortunately, the 68RFE Transmission Low/Reverse Drum is a generally powerful and durable system. However, there is one major flaw in this component that is worth understanding. This point of failure is known as "low/reverse sprag".

The Low/Reverse Sprag is a “roller clutch” style component that tends to physically snap or break at the rear end of the transmission due to impact. The reel seats inside the clamp body are plastic (seriously) and can withstand pretty much ANY impact. The impulse start is the number one cause of error here. A general rule of thumb here is simple: if you plan to unleash the momentum, plan to68RFEProject Carbon™ Reverse/Low Reamer.

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Spreaders are nothing new. In fact, they date back over half a century in the world of automatic transmissions. In the past, sprag solutions have included, but are not limited to: soldering the spragin position, bolting to the box, and more. All of this is implausible due to the location of the spring within the 68RFE gearbox; placed between two critical oil kitchens. Our only option is to deploy a stronger alternative.

Problem #7 - The valve body

The 68RFE broadcast community talks no more thanas hellvalve body. In fact, it was such a hot topic of discussion that we individually created our own Transmissions 101 post on the subject, seehere!However, we will cover wave peaks here.

As with the 68RFE transmission's high-pressure oil pump, the valve train is machined from aggressive, low-grade metals that are undesirable in their intended applications. The valve body is just no different.

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(Video) 68rfe Valve Body - Failures & Fixes | ATS Diesel

In fact, it's worse on every applicable metric. We simply tested the new 68RFE transmission valve bodies on data in the past and found that theyathas a noticeable cross-leakagestraight from the factory!The amount of cross leakage generally approached 2-3 inches of vacuum pressure. That's not enough to defeat the function of the valve body, but it's certainly not perfect.

With our thorough understanding of the 68RFE transmission's valve body, its leaking valves, accumulator system, separator plate and other immense imperfections, we can go back to the drawing board and use that knowledge to develop a truly superior product. That's why we're so proud of oursSeries of 68RFE valve bodies!Alternatively, our bestsellerProject Carbon™ 68RFE-Ventilkörper-Upgrade-KitIt's an amazing way to fix all of these problems at a fraction of the cost.

Tip: To avoid premature bore wear, regularly service the gearbox with our

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Problem #8 – The electronics

Automatic transmission electronics is always a risky business. This is actually not about the factory, but about the opposite. The aftermarket is notorious for trying to save money by making cheaper electronics overseas or sourcing them from third-party manufacturers. The problem here is that most manufacturers are smart enough to patent their own electronics, preventing the aftermarket from properly reproducing their quality.

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While not necessarily an industry standard, Next Gen Diesel includes in-box electronics with our 2-year unlimited mileage warranty. As a result, we need to compile data on the most likely failures as well as the most successful solutions available for this transfer.

What we've found time and time again is that true OEM electronics like the68RFE Mopar OEM Upgrade Solenoid Packare the only viable options for a successful transmission rebuild.

Problem #9 - The jacks (seriously!)

It's not common for bushings to be on a list, but we didn't make that list 'easy' for the 68RFE gearbox. Therefore, we must assert the lower factory bushings. The OEM bushing design is a very cheap and outdated Babbitt material, common in the diesel world but long forgotten in other parts of the transmission engineering industry.

The reason for this is that Babbitt bushings, by design, don't last very long. They typically have a lifespan of around 150,000 to 200,000 miles in average "peak bell curve" applications. At about twice the cost, upgrading to bronze bushings can become questionable. However, if we look at some basic scientific facts, we will see that the solution is right in front of us.

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The bushings in an automatic transmission have two enemies; One is heat, the other is oil pollution. Bronze is virtually impervious to both. Bronze is strong enough to withstand the effects of oil failures with minimal impact. In terms of heat, bronze is saturated (begins the process of transitioning from the solid to the liquid state of matter) at 1,742 degrees Fahrenheit at 14.7 PSI barometric pressure (sea level). The long and short is easy, you don't hurt the brass bushings, spend the extra $40. You will thank us in the future.

Problem #10 - The oil pan

The factory transmission oil pan was designed to achieve one thing only, and that is to save money. This pan is stamped from heated sheet steel that is not strong enough to withstand shock or abuse. The pans are also incredibly shallow, making the factory filters barely work properly.

This is an objectively terrible decision and does not contribute to the longevity, health or function of the transmission. One thing to consider when considering a deep transmission failure is the additional time between transmission maintenance intervals. Adding 20 to 30% more oil extends the time between transmission services by about the same amount. The same logic applies to heat as well.

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Other benefits of an aftermarket pan include the implementation of a drain plug. This makes servicing your transmission extremely quick, easy and clean. The works pan offers none of these benefits, making it the least qualified option of them all. ONE68RFE Transmission Deep Transmission Panoramashould be among your first considerations when updating this problematic transfer.

Problem No. 11 - That Flexplate

Flexplates are a very misunderstood part of the powertrain equation. It seems the only discussion in the flexible board market is how to ensure they don't break. While it's important to have a strong, well-balanced flexplate, the flexplate serves a higher purpose.

Think of the flexplate as a giant shock absorber for the torque converter. There is enormous pressure inside the torque converter, which can only escape between the outside diameter of the input shaft and the inside diameter of the oil pump stator bracket. If you're using an OEM pump, you're already at a huge disadvantage.

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The solution is a balanced flexible board that meets SFI approval standards. However, it should also be a flexible board that is not unnecessarily bulky or thick. This is a Pyrrhic victory (a greater loss than a victory in the Force) because overly large flexplates don't have the versatility or flexibility to truly serve their intended purpose. As a result, the moderate stiffness of our SFI-approved flexplates, as well as their overwhelming strength, make them credible advocates of healthy, successful gear design.


(Video) HAD TO GO REALLY BAD! Ram 2500 68RFE is toast

The 68RFE transmission has been talked about endlessly since 2007.5. It was an endless conversation about what works, what doesn't, and why. No two trucks are identical, nor should there be two 68RFE transmissions. However, with the data compiled above, you should be well on your way to making an informed decision as to which 68RFE gearbox or parts are right for your application. To learn more, clickhereor call and speak to one of our experts!

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What causes 68RFE to fail? ›

The most common failure point of the 68RFE is the Overdrive clutches. The OD clutch assembly from OE has significant weak points, even at stock power levels. Add increased engine power, larger tires or a heavy load, and there is a very high probability this will be the first failure of the 68RFE.

Can a 68RFE be reliable? ›

68RFE trucks can be identified easily because the transmission oil dipstick is on the passenger side of the engine bay. Despite all of the impending doom the 68RFE and it's abysmal valve body bring forth, it is a powerfully reliable transmission after being properly built.

How much does it cost to replace a 68RFE transmission? ›

Remanufactured 68RFE Transmission Price
$4204$1800In Store
$3879$1800In Store
$3925$1000In Store

Has the 68RFE been improved? ›

In 2019 Chrysler made several changes to the 68RFE. These changes included adding an auxiliary valve body, adding a dedicated TCC control solenoid, and changing the TCC regulator valve. Other changes include modifications to the valve body and the channel casting for controlled reverse and underdrive venting.

What temp should a 68RFE run at? ›

So here is a fact you should remember: the ideal maximum transmission temperature is 200°F. For every 20 degrees you go above 200 you reduce the expected life span of the transmission by a factor of 2. Simply put, at 220 degrees you can expect ½ the life span, at 240 a ¼ and at 260 it is reduced to 1/8th.

What are the symptoms of a failing diesel transmission? ›

Transmission failure - our bet is that it's not something you budget for on a regular basis.
5 Signs Your Diesel Transmission Needs Repair
  • Irregular Gear Shifting. ...
  • Grinding or Shaking Gears. ...
  • Is Your Car Noisier Than Usual? ...
  • Unusually Colored Transmission Fluid.
4 Dec 2017

How much HP can a stock 68RFE handle? ›

With quality transmission control module (TCM) tuning, the stock 68RFE can support 500rwhp and 1,000 lb-ft or more, but it won't survive boosted, four-wheel drive launches for very long—and maybe not even once if the Low/Reverse sprag explodes (which is common).

How strong is the 68RFE? ›

With the 68RFE locked in fifth gear and an open bottle of nitrous in the mix, the truck put down a jaw-dropping 1,436 hp and 2,578 lb-ft.

Can you tune a 68RFE transmission? ›

68RFE automatic transmission equipped trucks, you have the option to add transmission tuning. One of the major benefits of having such an electronically controlled transmission are that so many factors, such as converter lock up, line pressure, and shift patterns can be controlled electronically.

Is it cheaper to rebuild a transmission or buy a new transmission? ›

When repairing a transmission you are basically replacing the minimum amount of parts so that the transmission is brought back to good working condition. This typically costs less, so it is smart to get the right diagnosis of your transmission the first time around.

How many quarts of fluid does a 68RFE hold? ›

The 68RFE transmission with a deep pan requires at least 22 quarts of ATF to fill when completely dry. Transmissions equipped with the factory pan hold about 17 quarts of ATF.

Is it worth fixing a transmission? ›

If the price of a new transmission is no more than 40% to 60% of your car's value, then it's probably worth the cost of repair. If your transmission is in good condition, there are benefits to repairing it rather than scrapping it entirely.

Which heavy duty diesel truck is the most reliable? ›

The Most Reliable Diesel Trucks of All Time
  • 1999-2003 Ford F-250/F-350 Super Duty (7.3-Liter Power Stroke) ...
  • 2001-2004 Chevrolet Silverado/GMC Sierra 2500/3500 (6.6-Liter Duramax LB7) ...
  • 2006-2007 Chevrolet Silverado/GMC Sierra (6.6-Liter Duramax LBZ) ...
  • 1994-1998 Dodge Ram 2500/3500 (5.9-Liter, 12-Valve Cummins)
16 Jul 2022

What is the best Cummins engine ever made? ›

Cummins guys will fight until their dying breath that the Cummins 5.9 is arguably the best diesel engine ever made while CAT or PowerStroke gents will look in disbelief at the verbal diarrhea spewing forth from their buddies' mouths. The debate is as old as Rudolf Diesel himself.

Does 68RFE have overdrive? ›

One of the most common problems we keep seeing is the 68RFE overdrive clutches burning beyond recognition. Most of the overdrive clutch failures in these transmissions are due to valve body track erosion, which is caused by excessive torque from engines with tuners installed in the computer software.

How many quarts does a 68RFE filter change? ›

Add approximately 10 quarts for stock pan or 14 quarts for deep pan.

Does a 68RFE have a spin on filter? ›

This is an upgraded steel nipple to replace the plastic spin on nipple for the 68RFE spin on filter used on the 2007.5 to 2022 Ram trucks with the 68RFE transmission. A 1/2 Allen wrench is required to remove the nipple from the filter.

What transmission temp is too hot when towing? ›

When you're towing, the added drag and weight of the trailer will make your transmission work harder. Hard work means the internal temperature of your transmission will rise. What is this? To keep your transmission running at a safe temperature, keep the reading between 160 and 220 degrees.

How much does it cost to rebuild a diesel transmission? ›

What's the Diesel Transmission Rebuild Cost? While cost varies based on car model and other such factors, in most cases, you'll have to spend anywhere between $1,500 and $3,000 on the rebuild.

How do I know if my transmission is ruined? ›

What Are the Transmission Failure Symptoms?
  1. Refusal to Switch Gears. If your vehicle refuses or struggles to change gears, you are more than likely facing a problem with your transmission system. ...
  2. Burning Smell. ...
  3. Noises When in Neutral. ...
  4. Slipping Gears. ...
  5. Dragging Clutch. ...
  6. Leaking Fluid. ...
  7. Check Engine Light. ...
  8. Grinding or Shaking.
16 Mar 2017

What are the top 5 signs of transmission problems? ›

If you're having transmission problems, you might have any of these 5 symptoms:
  • Strange Smells.
  • Slipping Transmission (Delayed Reaction or Delayed Engagement)
  • Transmission Warning Light.
  • Transmission Fluid Leak.
  • Grinding or Odd Sounds.
17 May 2019

What is considered high mileage on a 6.7 Cummins? ›

Like the Duramax, Cummins diesel engines can be expected to last a long time. Between 350,000 and 500,000 miles is usually considered high mileage on a Cummins diesel.

What is the most powerful Cummins engine in a truck? ›

Producing up to 4,400 hp, the QSK95 is not only Cummins most powerful engine: it's the most powerful in the ULTRA-class truck category.

Who makes the Ram 68RFE transmission? ›

Unlike the 68RFE, which is built by Chrysler, Aisin Seiki and Aisin AW build the Aisin transmissions for use in RAM trucks and other Chrysler vehicles.

What is the toughest transmission? ›

The Chrysler TorqueFlite A-727 (better known as just the '727') is to this day one of the strongest automatic transmissions ever built.

What is the Holy Grail of Cummins? ›

Finding one of these truck in good shape is difficult but finding one with a 5-speed NV4500 manual transmission backing the Cummins is nearly impossible leading some Cummins enthusiasts to nickname it the Holy Grail.

What is the strongest truck transmission? ›

The Allison 1000 transmission, equipped in 2001 to present Chevrolet and GMC trucks of all types, is the single King of the transmission world.

What controls line pressure in a 68RFE? ›

Under most driving conditions, pump output greatly exceeds what's needed to keep the clutches applied. The 68RFE pressure control sys- tem monitors input torque and adjusts the pressure accordingly.

How many speeds does a 68RFE have? ›

The 68RFE has a design change that allows for fulltime 6-speed and increased torque ratios (figure 1).

How many hours does it take to rebuild a transmission? ›

Most repairs are fairly quick. Flushing the fluid, sealing, and recalibration can be done within a day. Replacing the shift solenoids takes a day or two. A full rebuild, however, is very time and labor-intensive and will typically take three to four days.

Are Rebuilt transmissions as good as new? ›

While a transmission rebuild involves incorporating many brand new gaskets, seals and other parts into your car's existing transmission, the core gears and their alignments remain the same and will still be ideal for your particular vehicle.

How much does it cost in labor to install a transmission? ›

The exact transmission cost will vary, based on your particular vehicle and your service department of choice, but you can expect to pay in the ballpark of $1,800 and $3,400 for brand new parts – and don't forget about the labor costs, which can run between $79 and $189.

What fluid does a 68RFE take? ›

This kit includes both transmission filters, 7 quarts of Mopar fluid, and pan sealant.

How often should you change transmission fluid Cummins? ›

Manual transmissions typically require service every 30,000 miles to 60,000 miles or so. The reason for this is that transmission fluid in manuals can get contaminated due to the wear and tear of components. Automatic transmissions usually require service every 60,000 miles to 100,000 miles or so.

What is 68RFE tuning? ›

2010-2018 68RFE Transmission calibrations optimize shift points and torque converter lock up, reduce shift times, and increase line pressure. Our transmission tuning offers you the highest level of performance and drivability in both stock and aftermarket transmissions!

Is it better to replace a transmission or buy a new car? ›

Transmission Mileage

If your car is manual or dual-clutch, the transmission can fail sooner than an automatic or automated manual. Opting for a brand-new transmission is best because spending money on repairs can be costlier and counterproductive over the years.

What does it cost to rebuild a transmission? ›

Replacements can range from $1,800 to $3,400. Depending on the repair shop and technicians, labor charges can range from $500 to $1,200. Here's a quick overview of the average transmission replacement cost: Remanufactured transmission – $1,300 to $3,400.

What happens when your transmission blows while driving? ›


In this case, your car could refuse to move, change gears, or there could be decreased or total lack of power while driving. If you are experiencing these problems take your car in immediately.

What is the longest lasting heavy duty truck? ›

The Honda Ridgeline comes in at first place in the category of trucks most likely to last 200,000 miles.

What is the most reliable diesel of all time? ›

1999-2003 Ford F-250/F-350 Super Duty (7.3-Liter Power Stroke) MotorTrend comes out of the gate with some oomph. The first choice for the most reliable diesel pickup trucks of all time is the 1999-2003 Ford F-250/F-350 Super Duty with the 7.3-Power Stroke plant.

How long should you let a diesel idle before driving? ›

Myth: Diesel engines need to warm up at idle for 5 to 10 minutes or more especially on cold days before driving them. Fact: This is one of the most common myths about diesel engines. Most engine manufacturers recommend that newer diesel engines idle for no more than 3 minutes before driving.

Which diesel engine has least problems? ›

The 7.3L Powerstroke is still considered one of the most reliable diesel engines ever made. It also has plenty of power for most applications, with 500 pound-feet of torque and 235 horsepower. It was built for the long haul, too with an air-to-air intercooler, oil-based fueling, and durable internal hard parts.

What is the strongest diesel engine in the world? ›

This jaw-dropper is the Wärtsilä RT-flex96C, the world's largest and most powerful diesel engine. Built in Finland, the RT-flex96C's fourteen cylinders can generate 107,389HP with more than 7,000,000Nm of torque — that's enough to power an entire suburban town.

Is Cummins a million mile engine? ›

The Cummins Million Mile Club recognizes owners of Cummins engines that have accumulated over one million miles in service.

Why does the 68RFE fail? ›

The most common failure point of the 68RFE is the Overdrive clutches. The OD clutch assembly from OE has significant weak points, even at stock power levels. Add increased engine power, larger tires or a heavy load, and there is a very high probability this will be the first failure of the 68RFE.

What causes Cummins turbo failure? ›

Undoubtedly the most common reason for turbocharger failures is the presence of problems in engine lubrication. If you have oil starvation this can lead to turbo failure and catastrophic engine damage. Oil Contamination. This could result from a poor-quality oil filter.

What are the signs of blown head gasket in 6.7 Cummins? ›

Bad head gasket symptoms
  • White smoke coming from the tailpipe.
  • unexplained coolant loss with no leaks.
  • Milky white coloration in the oil.
  • Engine overheating.

What year did Ram 2500 have transmission problems? ›

The transmissions that are related to common complaints and recalls for Dodge Ram trucks are five and six-speed automatic transmissions. These were found in the 2009 Dodge Ram and 2010 through 2017 Ram models 1500, 2500, 3500, 4500, and 5500.

How much power can a built 68RFE handle? ›

With quality transmission control module (TCM) tuning, the stock 68RFE can support 500rwhp and 1,000 lb-ft or more, but it won't survive boosted, four-wheel drive launches for very long—and maybe not even once if the Low/Reverse sprag explodes (which is common).

How often do Turbos need to be replaced? ›

Most turbochargers need to be replaced between 100,000 and 150,000 miles. If you are good at maintaining your car and get timely oil changes your turbocharger may last even longer than that.

What are the symptoms of a failed turbo? ›

The symptoms of a damaged or failing turbo are:
  • Loss of power.
  • Slower, louder acceleration.
  • Difficulty maintaining high speeds.
  • Blue/grey smoke coming from the exhaust.
  • Engine dashboard light is showing.

What does a failing turbo sound like? ›

Loud noises: If your vehicle has a bad turbo, you may hear loud noises that sound like whining or screeching. So if your vehicle is running and you hear a loud whining sound that increases in volume as the problem goes unfixed, this is most likely to do a turbo problem.

What happens if you drive a diesel with a blown head gasket? ›

Without this support, the engine will soon overheat if you keep driving – leading to further cracking and damage to your engine. And that can mean needing to pay for expensive repairs or replacement parts.

Can you drive a diesel with a blown head gasket? ›

Most of the time, trouble with your vehicle's head gasket starts out as a small crack before it is fully blown. Overtime, those cracks will widen if they aren't dealt with properly, leading to further damage and pricier repairs. That's why you should never drive with a cracked head gasket!

How can you tell the difference between a blown head gasket and a blown gasket? ›

When they blow, intake manifold gaskets and head gaskets will typically leak different substances. A blown intake manifold gasket may cause air or fuel to leak. A blown head gasket, on the other hand, will typically cause combustion gases, coolant or oil to leak.

What year Dodge Cummins to stay away from? ›

The Dodge Cummins engine has been around since 1989, providing power to the Dodge Ram. That's three decades of hard work - there are bound to be Dodge Cummins years to avoid after all that time. We recommend staying away from the 1991, 1992, 1993, 1999, 2001, 2003, 2006, 2007, 2008, and 2011 models.

What is the most reliable 2500 diesel truck? ›

Best Used Diesel Pickup Trucks To Buy
  • Dodge Ram 2500. When it comes to legendary long-lasting performance and durability, it's hard to beat a Ram 2500 heavy-duty pickup. ...
  • Chevrolet Silverado 2500HD. ...
  • Ford F-250 Super Duty. ...
  • Nissan Titan XD.

Who makes 68RFE transmission? ›

Unlike the 68RFE, which is built by Chrysler, Aisin Seiki and Aisin AW build the Aisin transmissions for use in RAM trucks and other Chrysler vehicles.


1. 68RFE Transmission Full Rebuild Part 1
(Automatic Transmission)
2. 2008 Ram 2500HD 68RFE Transmission Problems
(Phillip Bailey)
3. 68RFE Problems & Fixes
(The Diesel Podcast)
4. 68RFE Failure Causes
5. How to improve your 68RFE? Valve Body and Solenoid pack replacement 68RFE Sonnax BILLET
(Precision Transmission)
(pure panoRAMa)
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