Can I Trust A 3rd Gen 4-speed 48RE automatic transmission in a 2004 With 173K Miles?

[Goose55]

How reliable is the four-speed automatic transmission that comes with a 2004 Dodge ram 5.9 L Cummins diesel?

The 4-speed 48RE automatic transmission in a 2004 5.9L Cummins Ram is
generally considered the weakest link in an otherwise durable truck. While stock power levels and diligent maintenance (regular fluid changes/band adjustments) can provide decent longevity, they are prone to failure under heavy towing or engine tuning, often requiring upgraded torque converters or rebuilds.
Key Reliability Factors:

• Weak Points: The factory torque converter is a major weak point, and the transmission struggles with the high torque output of the 5.9L engine.
• Maintenance Needs: Requires meticulous maintenance, including regular band adjustments and fluid changes to prevent premature failure.
• Towing & Tuning: Increased power from engine tuners often leads to failure, while heavy, consistent towing can cause overheating.
• Common Issues: Potential problems include slipping, shuttle shifting, and governor pressure issues.

For longevity, many owners invest in aftermarket upgrades, such as those from ATS Diesel Performance.

 

[star_deceiver]

If it drives fine and shifts fine it’s probably fine. But rebuilt 48RE don’t cost that much so add a couple grand to the budget.

 

[hemihustlin]

how much power you looking to push through that transmission?