TransGo 48RE HD2 Reprogramming Shift Kit (TGO48RE-HD2)

This is the TransGo HD2 reprogramming kit, part number 48RE-HD2, for the Dodge 48RE four-speed used behind the 5.9L Cummins in 2003-2008 Ram 2500 and 3500 trucks. It is a full valve body recalibration, not just a couple of springs: the kit contains replacement valves, calibrated springs, spacers, a new separator plate, gaskets, shims, bushings and the hardware to install them.

The stock 48RE calibration lets the clutches and bands slip longer than they should under a heavy load or with added power. The HD2 kit raises the line pressure curve and firms up the apply of each element, which increases clutch holding capacity and shortens the overlap between shifts. That is what cuts down on the burnt direct clutch, worn front band and slipping overdrive that 48RE units are known for when towing or running a tuned diesel.

Install is done with the valve body out of the truck on a clean bench. Work through the TransGo instruction sheet one section at a time: disassemble the valve body, swap in the new valves and springs where directed, replace the separator plate and gaskets, drill or plug passages exactly as the sheet calls for, then reassemble and torque the bolts to spec. Plan to set the bands and do a fresh fluid and filter service when it goes back together. It pairs well with an overhaul, since new clutches last longer on the higher pressure.

This kit is built for the 2003-2008 electronically governed 48RE. Check the year and model of your transmission before ordering; earlier 47RE/47RH and 46RE units use a different kit.