8-Speed Automatic Transmission Assembly for 2019-2021 Ram 1500

A quick look at your own vehicle makes sure the right transmission shows up:

• Verify VIN indicates a 5th-generation 'New Style' Ram 1500 with 6-lug wheels.
• Confirm presence of the 48V eTorque system (look for the large aluminum RAM-branded box on top of the engine).
• Confirm 4x4 drivetrain with a transfer case.
• Locate the transmission ID tag on the driver's side rear bottom of the case to confirm '8HP75' and option code 'DFR'.

What the install really takes — plan and budget with confidence:

Special tools this job needs:

• Transmission jack
• E-Torx socket set
• Long T40 Torx bit (5 to 6 inches)
• 8mm hex socket (stubby or flexible)
• Bidirectional OBD2 scan tool (AlfaOBD, Autel, or Mopar wiTECH)
• Fluid transfer pump
• Torque wrench

Budget for these consumables at install:

• ZF Lifeguard 8 or Mopar 8 & 9 Speed ATF (part numbers 68218925AA/AB, 68157995AA/AB)
• Replacement plastic transmission pan assembly with integrated filter (Mopar 68225344AA or equivalent)
• Torque converter seal (front pump/input shaft seal)
• Rear output shaft seal
• Cooler-line flush solvent

What your vehicle’s computers will need after the swap:

What’s involved: TCM Adaptive Relearn (Quicklearn) and VIN-specific programming

sources differ: Arm 1 states TCM is integrated into the mechatronics unit and requires VIN-specific programming/flashing to match the truck's VIN/PCM; Arm 2 states TCM is a separate unit not included. Both agree a TCM adaptive relearn (Quicklearn) using a dealer-level scan tool (wiTECH, AlfaOBD, or Autel) is mandatory to prevent limp mode or harsh shifting.

Pro tips for a smooth first start-up — hand them to whoever does the install:

• Torque converter must be fully seated (clicking/dropping 3 times) before bolting to engine to avoid cracking the internal oil pump gear.
• Exhaust Y-pipe blocks access to drain/fill plugs and pan bolts; must unbolt exhaust or lift transmission 2-3 inches.
• Rear three pan bolts are obstructed by the crossmember and require a 5-6 inch long T40 Torx bit to prevent stripping.
• Fluid level must be checked with engine running, vehicle level, and fluid temperature strictly between 30°C (86°F) and 50°C (122°F).
• Factory plastic drain plug has a 10mm hex head that rounds out easily.
• Plastic oil pan bolts have very low torque specs and must be tightened in sequence to prevent cracking.

Easy to get right once you know them:

• Ordering for a non-eTorque (standard 12V) truck.
• Ordering for a 2WD truck (which has a different tailhousing and output shaft).
• Reusing the old plastic pan and contaminated integrated filter.
• Using generic ATF or ATF+4 instead of ZF Lifeguard 8 / Mopar 8 & 9 Speed fluid.
• Failing to perform the TCM adaptive Quicklearn reset before driving.
• Failing to professionally flush the transmission cooler lines.

Not issues with the units on this page — the manufacturer documented these for every transmission of this family, wherever you buy one. Handy for your installer: