ATSG 48RE Transmission Repair and Rebuild Manual

This is the ATSG TechTran technical manual for the Chrysler 48RE, the heavy-duty four-speed automatic bolted behind the 5.9L Cummins in 2003-2007 Ram 2500 and 3500 trucks. The same book covers the 46RE and 47RE, so it carries the whole A518/A618 electronic family from the early 46RE Grand Cherokee and Dakota units through the 47RE and on to the 48RE. If you work on RE-series Mopar units at all, this is the reference that stays open on the bench.

Content is the material you need with the case split: principles of operation for each gear range, the clutch and band application chart, governor pressure solenoid and governor pressure transducer operation, valve body identification and separator plate differences between the 46RE, 47RE and 48RE, electrical diagrams with wiring harness and connector locations, and the full disassembly and reassembly sequence with component identification photos. Diagnosis and troubleshooting charts are included alongside the electronic control section.

The reason this book earns its space is the governor circuit. Most 47RE and 48RE complaints that walk in the door - no 3-4 shift, harsh or delayed shifts, a truck that stays in second, a lockup that will not release - trace back to a governor pressure solenoid, a failed transducer, or a worn governor bore in the valve body. The pressure charts in this manual let you decide whether you are chasing electronics or a mechanical problem before you drop the pan, and the valve body ID pages keep you from installing the wrong separator plate on reassembly.

ATSG (Automatic Transmission Service Group) writes these TechTran manuals for working rebuilders, not for the parts counter. Printed format, 11 x 8.3 inches, roughly 13 ounces, sized to lay flat next to a torn-down unit.