Dodge Ram 68RFE Automatic Transmission

The Dodge Ram 68RFE Automatic Transmission, introduced by Chrysler in 2007.5, is a 6-speed electronically controlled transmission designed specifically for use behind diesel engines, especially the 6.7L Cummins Turbo Diesel found in Ram 2500 and 3500 heavy-duty trucks. The Dodge Ram 68RFE Automatic Transmission has since become one of the most discussed transmissions in the diesel community—praised for its towing capabilities but also criticized for certain reliability issues, especially under heavy stress or modification.

Whether you’re looking to better understand your Ram’s drivetrain, plan upgrades, or avoid common pitfalls, this guide will cover everything you need to know about the Dodge Ram 68RFE Automatic Transmission.

Background & Development

Before the Dodge Ram 68RFE Automatic Transmission, Ram diesel trucks used the 48RE, a 4-speed transmission that served well in the early 2000s. However, as emissions regulations tightened and engine power increased (especially with the release of the high-output 6.7L Cummins), there was a need for a more advanced, electronically integrated transmission with better fuel economy and towing performance.

The Dodge Ram 68RFE Automatic Transmission was Chrysler’s response—a modern 6-speed automatic based loosely on the 545RFE/45RFE architecture used in gas-powered trucks and SUVs but beefed up with heavier internal components and enhanced shift control logic.

Technical Specifications

Here’s a breakdown of the core technical specifications of the Dodge Ram 68RFE Automatic Transmission:

The wide gear ratio spread helps with both low-speed torque and high-speed efficiency, while the overdrive 5th and 6th gears reduce engine RPM at highway speeds, improving fuel economy.

Applications and Fitment

The Dodge Ram 68RFE Automatic Transmission is found in the following vehicles:

• 2007.5–2024 Ram 2500 & Ram 3500 (with 6.7L Cummins)

• Some commercial chassis cab models with similar powertrains

It is not used in Ram 1500s, nor is it paired with gasoline engines. The HEMI-powered trucks generally use the 545RFE, 65RFE, or 66RFE, while higher-output Cummins trucks (usually with the High-Output engine) may come with the Aisin AS69RC transmission instead.

Internal Design Features

The Dodge Ram 68RFE Automatic Transmission internal structure features several key improvements over its predecessors:

• Reinforced torque converter with lockup clutch

• 6-clutch packs (instead of 5 in earlier 545RFE designs)

• Larger planetary gear sets

• Low clutch-to-clutch overlap, improving shift quality

• Full electronic valve body with solenoid controls

Despite these upgrades, many components—especially in early models—still suffered from wear and were not always capable of handling the full torque output of tuned or heavily loaded trucks.

Common Issues and Failure Points

While the Dodge Ram 68RFE Automatic Transmission can perform well in stock applications, it’s known to have certain reliability issues—especially when subjected to hard towing, aggressive tuning, or high-mileage wear.

 Common Issues Include:

1. Torque Converter Failure

• The factory converter often wears out under high load.

• Symptoms include slipping, shuddering, or overheating.

• Converter clutch failure can lead to contamination of the transmission fluid.

2. Valve Body Malfunction

• Electronic solenoids and internal passages may fail or stick.

• Leads to delayed or harsh shifting, erratic gear behavior, and fault codes.

• This is one of the most commonly replaced parts on the Dodge Ram 68RFE Automatic Transmission.

3. Overheating

• Insufficient cooling during heavy towing or hill climbs.

• Transmission temperature sensors may not accurately detect heat until damage occurs.

• Prolonged overheating leads to fluid breakdown and premature component wear.

4. Clutch Pack Wear

• Over time, friction clutches (especially in 4th and 5th gear) can wear down.

• Can cause slipping, poor acceleration, or transmission fault codes.

• Performance tuning accelerates this wear significantly.

5. Inadequate Line Pressure

• The factory TCM tuning keeps pressure too low under load.

• Leads to clutch slippage and long-term damage.

• Can be corrected with tuning or valve body upgrades.

Maintenance Recommendations

Proper maintenance can dramatically improve the lifespan of the Dodge Ram 68RFE Automatic Transmission.

 Fluid & Filter Service:

• Interval: Every 30,000–50,000 miles

• Fluid: Mopar ATF+4 or equivalent full synthetic

• Filter Replacement: Use OEM or high-quality aftermarket filters

 Cooling:

• Install a transmission temperature gauge if towing.

• Consider a larger aftermarket cooler to reduce heat during hauls.

 Regular Inspections:

• Look for burnt or discolored fluid.

• Check for metal shavings in the pan.

• Scan for codes like P0868 (line pressure low) or P0750-P0770 (solenoid faults)

Performance Tuning and Aftermarket Upgrades

The Dodge Ram 68RFE Automatic Transmission is a common subject of performance modifications. Here’s what you should know:

 Transmission Tuning:

• Tuning the TCM increases line pressure, adjusts shift points, and improves clutch engagement.

• Companies like EFILive, MM3, or HP Tuners allow custom TCM tuning.

• Always match transmission tuning with engine tuning for reliability.

 Recommended Upgrades:

Cost Estimates:

• Basic rebuild: $2,500–$4,000

• Performance build: $5,000–$8,000+

• Standalone valve body: $700–$1,200

• Torque converter: $900–$2,000

Comparison to Other Transmissions

The Dodge Ram 68RFE Automatic Transmission isn’t the only transmission option for heavy-duty Ram trucks.

While many prefer the Aisin for its torque handling (up to 1,050 lb-ft), the Dodge Ram 68RFE Automatic Transmission is easier and cheaper to rebuild or upgrade with aftermarket parts.

Best Practices for Longevity

If you want your Dodge Ram 68RFE Automatic Transmission to last beyond 200,000 miles, here are some essential tips:

1. Avoid Excessive Tuning without proper supporting mods.

2. Install a deep transmission pan for better cooling and fluid capacity.

3. Use high-quality fluid and service regularly.

4. Upgrade the torque converter if towing regularly.

5. Monitor transmission temps using a digital gauge.

Conclusion

The Dodge Ram 68RFE Automatic Transmission is a decent factory transmission with a strong foundation but has well-known shortcomings when pushed beyond stock limits. For most daily drivers and light-duty towers, it performs adequately—especially if maintained properly. But for truck owners with performance tuning, heavy towing, or high-mileage needs, the factory 68RFE can become a weak point.

Fortunately, the aftermarket support is strong. With a few key upgrades—like a better torque converter, valve body, and tuning—the Dodge Ram 68RFE Automatic Transmission can become a reliable transmission capable of handling over 1,000 lb-ft of torque.