The 68RFE transmission is a heavy-duty automatic transmission used in many Dodge Ram trucks. While it was designed for power and durability, 68RFE transmission failure is a common issue owners encounter—especially under heavy towing, high-horsepower, or poor maintenance conditions.

What is the cause of a 68RFE transmission failure?

Did you ever wonder what causes a 68RFE transmission to meet an early demise? Below are the most frequent causes of 68RFE transmission failure and what you can do to prevent them.

Torque Converter Failure

The torque converter transfers power from the engine to the transmission. When its lockup clutch slips or fails, it creates excessive heat and metal debris that circulates through the system. That contamination burns seals, damages clutch packs, and causes slipping or shuddering.

Why it fails:

• Weak single-disc lockup design

• Low line pressure

• Contaminated or overheated fluid

How to prevent it:Upgrade to a triple-disc billet torque converter with stronger lockup clutches, anti-ballooning plates, and precision balancing. It keeps power transfer efficient and eliminates converter shudder under load.

Valve Body Issues

The valve body is the hydraulic brain of the 68RFE. It controls fluid flow to engage gears and clutch packs. When passages wear out or valves leak, you get erratic shifting, delayed engagement, or harsh upshifts.

Why it fails:

• Poor factory machining tolerances

• Cross-leaks and worn valves

• Contaminated transmission fluid

How to prevent it:Install a billet aluminum valve body engineered for precision and durability. RedLine’s billet valve body improves fluid control, increases clutch holding power, and stabilizes line pressure — keeping your 68RFE alive under extreme load.

Clutch Pack Burnout

Clutch packs are responsible for engaging and holding each gear. When they lose hydraulic pressure or face excessive heat, they slip and burn — turning friction material into sludge that spreads through the transmission.

Why it fails:

• Low line pressure

• Weak valve body calibration

• Insufficient cooling when towing

How to prevent it:Upgrade to performance clutch packs with high-energy friction plates and stronger steels. Combine them with a high-pressure pump and billet valve body for stable engagement and long-term durability.

Solenoid and Electrical Failures

The solenoid pack controls hydraulic pressure electronically. When it fails, shift timing goes out the window — leading to erratic gear changes or loss of specific gears.

Why it fails:

• Overheating

• Fluid contamination

• Poor electrical grounding

How to prevent it:Replace with a heavy-duty solenoid block featuring upgraded seals, improved circuitry, and better fluid isolation. Keep fluid clean and temperatures low with an upgraded cooler system.

Overheating

Heat is the #1 enemy of every automatic transmission. At 220°F, fluid breaks down; at 250°F, clutch life drops dramatically. The 68RFE’s stock cooler simply can’t keep up with heavy towing or modified trucks.

Why it fails:

• Slipping torque converter

• Weak factory cooler

• Excess fluid aeration

How to prevent it:Add a high-capacity auxiliary cooler and change transmission fluid regularly. Keep your converter locked when possible and ensure your line pressure stays strong. Cooler fluid means longer clutch life.

Underload and Line Pressure Drops

Most people assume towing kills transmissions — but running too little pressure under light load can be just as damaging. The factory programming often lowers pressure when it shouldn’t, letting clutches slip and wear prematurely.

Why it fails:

• Factory tuning drops line pressure

• Weak pump output

• Internal cross-leaks

How to prevent it:Upgrade to a high-pressure pump and custom tuning that maintains proper clutch pressure across all conditions. Consistent pressure equals consistent reliability.

Input and Output Shaft Failure

When you add power or towing stress, the 68RFE’s input and output shafts become weak links. A twisted or snapped shaft instantly ends the drive and often ruins the converter and case.

Why it fails:

• Soft factory steel

• Shock loads from aggressive driving

• Excess torque from tuned engines

How to prevent it:Install billet input and output shafts made from 300M or Maraging steel. They resist twisting and breakage under massive torque — critical for performance or heavy towing.

The 68RFE transmission fails not because it’s badly designed, but because it’s underbuilt for the real torque of a 6.7L Cummins. Every weak link — from the torque converter to the valve body — has a proven upgrade.

When you build a RedLine 68RFE, you get:

• A triple-disc billet torque converter

• A billet valve body with precision hydraulic control

• A high-pressure pump for consistent line pressure

• Billet shafts, performance clutches, and superior assembly standards

At RedLine Transmissions, we don’t just rebuild — we re-engineer. Every RedLine 68RFE transmission is built to outperform, outlast, and out-tow anything else on the road.

Ready to Build Your 68RFE the Right Way?

Don’t wait for a failure to happen.Upgrade your 68RFE with a RedLine performance transmission built to handle real-world torque, towing, and horsepower. Explore our full line of 68RFE transmission builds

At RedLine Transmissions, we don’t just rebuild—we re-engineer. Every RedLine 68RFE transmission is built to outperform, outlast, and out-tow anything else on the road.

RedLine Builds It Better. For you.