48RE Master Rebuild Kit 2004, new and ready to install. Fits the 48RE. Ships fast from the USA.
A 2004 Ram 2500 or 3500 with the 5.9L Cummins that slips on the 3-4 shift with a load behind it, won't hold overdrive, or has black fluid and friction material in the pan is past the point of a fluid service. This new 48RE master rebuild kit for the 2004 model year is the parts side of a full overhaul. The kit photo shows bands, friction discs, steel plates, a pan filter, the gasket set, lip seals, sealing rings and O-rings, so the unit can be resealed and every clutch pack renewed at once.
The 48RE is a three-speed main box, with front and rear clutches and a front kickdown and rear low-reverse band, plus a bolt-on overdrive section with its own overdrive and direct clutches. Sonnax notes that 48RE production began in 2003 with clutch pack and gear train changes over the 47RE. The factory spec table lists 5 front clutch discs, 4 rear, 5 overdrive discs on the standard build or 6 on the Diesel HO, and a 23-disc single-sided direct clutch stack. That direct pack is the reason a 48RE kit costs more than a light-duty four-speed kit. A master kit covers the soft parts plus the wear items; an overhaul kit covers seals and gaskets only.
Check level and condition with the engine idling, fluid hot and the selector in Neutral. Pull the pan and look at what is in it. Make sure the problem is not electrical: a dropped transmission control relay puts the truck in third-gear limp mode and can look like a dead transmission. Our 48RE Cummins problems guide walks through what actually fails on these trucks, and the 48RE rebuild cost breakdown shows where the bill grows once hard parts are found bad.
This kit is listed for 2004 48RE units in Ram 2500 and 3500 Cummins trucks. Two things to check on a 2004 build. First, count the overdrive clutch pack on teardown, because the spec splits it between 5 and 6 discs depending on the version. Second, a 2004 diesel still uses the cable-type throttle valve system; Transmission Digest dates the throttle valve actuator to 2005 diesel trucks. If you are unsure which version you have, send us your year and VIN before ordering. Our 2003-2007 master kit and the rest of the 48RE parts are listed for comparison.
Most 2004 rebuilds also benefit from a 48RE shift kit to correct known valve body wear, and if the pump is scored, a replacement 48RE pump is cheaper than a comeback.
| Fits | 48RE 2004 |
| Part type | Master Rebuild Kit |
| Condition | New |
| Brand | OEM |
| Ships | From the USA |
| Warranty | 1-year |
Doing this repair right usually means replacing these at the same time. Same transmission, ships together.
The kit photo shows bands, friction discs, steel plates, a filter, gaskets, lip seals, sealing rings and O-rings. It does not include hard parts such as drums, the pump, shafts or the torque converter.
Do not count on it. Sonnax notes the 48RE has clutch pack and gear train changes over the 47RE, and the clutch counts in a 48RE are specific, including a 23-disc direct clutch pack.
The factory spec lists 5 overdrive discs on the standard build and 6 on the Diesel HO. Count the pack when you take it apart, or send us your VIN before ordering.
Plan on a converter, a cooler and line flush, and a new drainback valve. Inspect the pump, input shaft, bushings and thrust washers. Many rebuilders add a shift kit to correct valve body wear.
A pan-and-filter service takes about 8 pints of ATF+4, but an overhaul fill is 29 to 33 pints per Chrysler's capacity chart. Set the final level hot, in Neutral, with the engine idling.
