Product Description
The REVMAX 478-604 Low Reverse Drum is a high-quality replacement component designed for 47RH, 47RE, and 48RE automatic transmissions used behind the legendary 5.9L Cummins diesel engine. The low reverse drum is a critical internal transmission component responsible for holding the low/reverse clutch assembly during reverse and low gear operation.
Over time, the inside of the drum can become scored or worn due to heat, debris, or restricted cooler flow. When this occurs, clutch engagement and transmission reliability can suffer. Replacing the drum during a rebuild helps restore proper clutch engagement and prevents future failure.
The RevMax 478-604 is engineered as a direct replacement for factory components and is commonly installed during transmission overhauls to ensure proper operation of the low/reverse clutch pack.
Key Features:
- Direct replacement low reverse drum
- Designed for heavy-duty diesel transmission applications
- Restores proper operation of the low/reverse clutch assembly
- Ideal during full transmission rebuilds
- High-quality construction for long service life
Fitment:
- 1994–2002 Dodge Ram 2500 / 3500 – 5.9L Cummins with 47RH transmission
- 1996–2002 Dodge Ram 2500 / 3500 – 5.9L Cummins with 47RE transmission
- 2003–2007 Dodge Ram 2500 / 3500 – 5.9L Cummins with 48RE transmission
| Specifications for REVMAX 478-604 | |
|---|---|
| UPC | 193564455130 |
| GTIN | 193564455130 |
| Shipping Info | Shipping Weight: 6 lbs Package Dimensions: 10 in x 10 in x 6 in |
| Prop 65 | WARNING: Cancer & Reproductive Harm – www.P65Warnings.ca.gov |
FAQ
What does the low reverse drum do in a 47RE or 48RE transmission?The low reverse drum houses the clutch pack responsible for holding the transmission in reverse gear and low gear operation. If the drum becomes worn or scored, clutch engagement can suffer.
When should the low reverse drum be replaced?
It should be replaced anytime the internal surface shows scoring, heat damage, or wear. Many builders replace it proactively during a full transmission rebuild.
Will this fit both 47RE and 48RE transmissions?
Yes. The RevMax 478-604 is designed for use with 47RH, 47RE, and 48RE Dodge Cummins transmissions.
Is this an OEM replacement or upgraded part?
This drum is designed as a direct replacement for the factory component, making it ideal for transmission rebuilds or repair situations.
Do I need additional parts during installation?
If the drum shows wear, it is recommended to inspect or replace the governor support housing and clutch components that ride against it during the rebuild process.
