The 68RFE transmission, widely used in Dodge and Ram trucks, is a workhorse for heavy-duty applications. However, when it comes to towing, especially heavy loads, it can be pushed to its limits. Upgrading your 68RFE can significantly improve its reliability, performance, and durability. Here’s a comprehensive guide on upgrading your 68RFE for better towing performance.
Understanding the 68RFE Transmission
The 68RFE is a six-speed automatic transmission designed for heavy-duty applications, commonly paired with the Cummins 6.7L turbo diesel engine. While robust, it has certain weaknesses when faced with high torque and heavy towing:
- Heat Build-Up: Towing generates excessive heat, which can degrade the transmission fluid and wear out internal components.
- Weak Internal Components: Stock clutches, valve bodies, and torque converters may not handle extended towing stress.
- Limited Line Pressure: Stock line pressure limits holding capacity, leading to clutch slippage under high loads.
Addressing these shortcomings through targeted upgrades can transform your 68RFE into a towing powerhouse.
1. Upgrade the Torque Converter
The torque converter is a critical component for transferring engine power to the transmission. The stock torque converter in the 68RFE is prone to overheating and slippage during heavy towing.
Solution:
- Install a heavy-duty billet torque converter. These are designed to handle higher torque loads without overheating or slipping.
- Look for models with a multi-disc lock-up clutch for enhanced durability during long hauls.
Benefits:
- Improved power transfer.
- Reduced heat generation.
- Enhanced towing efficiency.
2. Reinforce the Valve Body
The valve body regulates hydraulic pressure and controls gear shifting. Under heavy towing conditions, the stock valve body may struggle to provide consistent line pressure, leading to gear slippage and heat build-up.
Solution:
- Upgrade to a performance valve body. Aftermarket options provide higher and more consistent line pressure to improve clutch engagement.
- Install a shift kit for faster, firmer shifts.
Benefits:
- Reduced clutch wear.
- Improved gear holding capacity.
- Smoother, more reliable shifting under load.
3. Increase Line Pressure
The 68RFE’s stock line pressure is often insufficient for heavy towing. Low pressure can cause clutches to slip, leading to premature wear.
Solution:
- Install a tuning device or pressure booster to increase line pressure.
- Many tuners also allow you to adjust transmission shift points and firmness to optimize towing performance.
Benefits:
- Stronger clutch engagement.
- Reduced likelihood of slippage.
- Improved longevity of internal components.
4. Upgrade the Transmission Cooler
Heat is the number one enemy of any transmission. Towing places a heavy thermal load on the 68RFE, especially in warm climates or mountainous terrain.
Solution:
- Install a high-capacity external transmission cooler. Plate-and-fin designs are more efficient than the stock cooler.
- Add a temperature gauge to monitor fluid temperatures and prevent overheating.
Benefits:
- Lower transmission temperatures.
- Extended fluid and component life.
- Improved reliability during long towing trips.
5. Strengthen the Clutch Packs
The 68RFE’s clutch packs are a known weak point under high torque loads. Prolonged slippage can lead to overheating and failure, particularly during heavy towing.
Solution:
- Upgrade to aftermarket clutch packs with higher friction material and increased holding capacity.
- Look for kits with additional clutches to increase surface area and improve durability.
Benefits:
- Better power handling capability.
- Reduced wear and tear.
- Enhanced performance under heavy loads.
6. Replace the Input Shaft
The stock input shaft in the 68RFE is sufficient for standard applications but may fail under the high torque loads associated with heavy towing.
Solution:
- Replace the stock input shaft with a billet steel shaft. These are designed to withstand significantly higher torque levels.
Benefits:
- Greater durability.
- Reduced risk of catastrophic failure.
7. Upgrade the Overdrive Clutch Assembly
The overdrive clutch assembly is another weak link in the 68RFE, particularly during prolonged highway towing.
Solution:
- Install a heavy-duty overdrive clutch assembly. These kits typically include upgraded clutches, steels, and stronger components to handle increased stress.
Benefits:
- Improved reliability in overdrive.
- Reduced wear during extended towing.
8. Install a Deep Transmission Pan
A deep transmission pan increases fluid capacity, which helps manage heat more effectively and improves lubrication.
Solution:
- Upgrade to an aftermarket aluminum deep pan with cooling fins and a drain plug for easy fluid changes.
Benefits:
- Improved cooling performance.
- Extended fluid life.
- Easier maintenance.
9. Use High-Quality Transmission Fluid
The quality of transmission fluid directly impacts performance and longevity. For towing, it’s essential to use fluid that can withstand high temperatures and stress.
Solution:
- Switch to a synthetic transmission fluid specifically designed for heavy-duty applications.
- Follow recommended fluid change intervals, especially after prolonged towing.
Benefits:
- Improved thermal stability.
- Reduced wear on internal components.
- Enhanced shifting performance.
10. Consider a Complete Transmission Rebuild
If you frequently tow heavy loads and your 68RFE has high mileage, a complete transmission rebuild may be the best option.
Solution:
- Opt for a performance rebuild kit that includes upgraded clutches, steels, bands, and other critical components.
- Work with a reputable transmission shop experienced with 68RFE upgrades.
Benefits:
- Comprehensive improvement in performance and durability.
- Peace of mind during heavy towing.
11. Tune the Engine and Transmission Together
A proper tune ensures that your engine and transmission work in harmony, optimizing towing performance and reliability.
Solution:
- Invest in a custom tune tailored for towing.
- Ensure that the tuner adjusts shift points, line pressure, and lock-up timing for maximum efficiency.
Benefits:
- Increased power and torque.
- Smoother shifting under load.
- Improved fuel economy during towing.
Conclusion
Upgrading your 68RFE transmission for better towing performance involves a combination of targeted upgrades to address its known weaknesses. Whether it’s enhancing the torque converter, improving cooling, or increasing clutch capacity, each upgrade contributes to a more robust and reliable transmission.
By investing in these upgrades, you’ll not only enhance your towing experience but also extend the life of your transmission, ensuring that your truck remains a dependable workhorse for years to come.
