48RE Shift Kit 2003-2008, new and ready to install. Fits the 48RE. Ships fast from the USA.
If your Ram 2500 or 3500 with the 5.9L Cummins or 8.0L V10 and a 48RE shifts soft, flares into third or overdrive under a load, or the converter clutch slips once the engine has been turned up, this TransGo valve body kit is aimed at that problem. It is a new TransGo 48RE kit in TransGo's current Reprogramming Kit packaging, built for the 2003-2008 diesel and V10 48RE. TransGo's own instructions say the kit increases torque capacity, firms up lockup and shifts, and reduces converter drainback, and call it perfect for diesel trucks.
The 48RE is a hydraulically shifted four-speed. The governor pressure solenoid and transducer schedule the 1-2 and 2-3 shifts, separate solenoids handle overdrive and converter lockup, and line pressure is set by the pressure regulator valve and the throttle valve, which on 2005 and later diesel trucks is moved by an electronic throttle valve actuator instead of a cable. A stock valve body is calibrated for comfort, not for a Cummins making more torque than the factory. This kit changes the pressure regulator springs, adds a check ball and accumulator spring changes, installs a new design manual valve that keeps the converter charged in Park, and adds a lockup bracket, so the clutches and bands apply faster and harder and spend less time slipping.
A shift kit corrects calibration, not broken parts. If the truck is already slipping, a code is set, or the fluid is burnt, find out why first. Our 48RE harsh and delayed shifts guide covers pressure and governor causes, and 48RE shift solenoid symptoms shows how to test the overdrive and lockup solenoids. TransGo also warns that wear in the boost valve bore causes repeated rear band failure and lazy pressure rise, so check that bore while the valve body is out.
TransGo lists this kit for 2003-2008 48RE units in diesel and V10 trucks. Two checks matter before you order. First, TransGo says to read the 8th digit of the VIN: C is a 48RE and 6 is a 47RE. Second, the kit only fits valve bodies that have the balance hole in the main separator plate shown in the instructions; if your plate does not have it, TransGo directs you to its TFOD-Diesel kit instead. It is also not compatible with a 46/47RE hybrid valve body or a 48RE body already modified by someone else. See every 48RE part we carry on our 48RE parts page.
| Fits | 48RE 2003-2008 |
| Part type | Shift Kit |
| Condition | New |
| Brand | TransGo |
| Ships | From the USA |
| Warranty | 1-year |
Doing this repair right usually means replacing these at the same time. Same transmission, ships together.
It fits 2003-2008 48RE transmissions in diesel and V10 trucks. Check the 8th digit of your VIN: TransGo says C means a 48RE and 6 means a 47RE. Then confirm your separator plate has the balance hole shown in the instructions.
The kit firms shifts and lockup on purpose. TransGo makes several steps optional, such as the extra lockup holes and the green TV spring, so you can tune it. TransGo also notes that a triple disc converter in a stock daily driver can lead to rough 3-4 or lockup complaints.
No. The kit installs in the valve body, which comes out through the pan. A few steps involve drilling and filing the valve body, so it is best done on a bench with the instructions in front of you.
This one is TransGo's 48RE kit in the current Reprogramming Kit packaging for the full 2003-2008 range. Both follow TransGo's 48RE instructions; the right choice depends on your year and valve body, and we can help if you send your VIN.
ATF+4. Check the level hot in Neutral, since the new manual valve keeps the converter charged in Park and gives a misleading reading there.
