8-Speed Automatic Transmission Assembly for 2019-2024 Ram 2500, 3500

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

• Verify the 8th digit of the VIN is 'J' (6.4L Heavy Duty Hemi V8 engine).
• Confirm the vehicle is a 4x4 (four-wheel drive) model.
• Verify the transmission sales code is DFX (8-speed automatic 8HP75-LCV) and not DG7 (6-speed 68RFE).
• Locate the barcode sticker or metal tag on the driver's side of the transmission case to verify part number 68449199AA or P52854997AB.

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

Special tools this job needs:

• Heavy-duty transmission jack
• High-clearance jack stands
• Torque converter clutch alignment tool
• Fluid transfer pump
• Professional-grade scan tool (wiTECH 2.0 or AlfaOBD)
• Security Gateway (SGW) bypass module (for 2018+ Ram trucks)
• Extensions and swivels for bellhousing/torque converter bolts
• Cooler line disconnect tool

Budget for these consumables at install:

• Mopar 8 & 9 Speed ATF or ZF Lifeguard 8 fluid (approx. 9.0 quarts for dry fill, 5.5 to 7.0 quarts for service fill)
• Integrated filter and plastic oil pan assembly (Mopar 68225344AA or ZF equivalent)
• New single-use aluminum pan bolts
• Torque converter seal (front pump/input shaft seal)
• Transfer case adapter seal
• Engine rear main seal (recommended best practice)
• Professional-grade transmission cooler line flush solvent/machine

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

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

The replacement TCM must be flashed with the vehicle's specific VIN and configuration using a dealer-level scan tool (wiTECH 2.0) or compatible advanced aftermarket tool (AlfaOBD). Skipping this step will trigger security codes, limp-home mode, or prevent starting. An adaptive memory reset/Quick Learn is mandatory before driving.

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

• Torque converter must be fully seated with three distinct clicks/drops before bolting to the engine. Failure to seat it fully will crack the internal oil pump gear upon tightening.
• Strict fluid fill procedure: No dipstick is present. Fluid must be filled through the side plug and checked with the engine running, vehicle level, and fluid temperature strictly between 30°C and 50°C (86°F to 122°F).
• Aluminum pan bolts are single-use torque-to-yield and must be replaced to prevent snapping or fluid leaks.
• A complete cooler and line flush is mandatory to prevent debris from the failed transmission from contaminating the replacement unit.
• Torque converter bolts are accessed by removing the starter motor; do not use impact tools on these bolts to avoid rounding.

Easy to get right once you know them:

• Ordering the wrong 8HP75 variant (e.g., from a Ram 1500 5.7L or Jeep) which has a different bellhousing, case casting, and tailhousing.
• Failing to perform the electronic Quick Learn adaptive reset before driving, leading to immediate clutch damage.
• Checking the transmission fluid level with the engine off, which results in severe underfilling.
• Skipping the transmission cooler and line flush, causing immediate contamination and failure of the replacement unit.
• Assuming the transmission is plug-and-play without performing the required TCM VIN programming.

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: