6-Speed Automatic Transmission Assembly for 2015-2017 Chevrolet & GMC

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

• Verify AWD drivetrain by checking for a rear differential and driveshaft.
• Verify engine size is the 2.4L 4-cylinder (not the 3.6L V6).
• Check the SPID sticker in the glove box or spare tire well for RPO code MHC.
• Locate the metallic ID tag on top of the transmission case and verify the 4-character code matches a 2015-2017 AWD 2.4L calibration (e.g., 5EGW, 5MDW, 6EGW, 6MDW).

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

Special tools this job needs:

• Transverse engine support bar
• Transmission jack
• Subframe/cradle jacks
• GM-compatible scan tool (GM MDI or J2534 pass-thru)

Budget for these consumables at install:

• DEXRON-VI automatic transmission fluid (approx. 9.0 quarts / 8.5 liters for dry fill)
• Torque converter seal (GM Part #24230687 or equivalent)
• Left and right axle seals
• High-pressure transmission cooler-line flush solvent
• Side cover (valve body cover) gasket (if opened for inspection)

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

What’s involved: VIN-Specific Programming & Transmission Adaptive Relearn (Fast Learn)

The TEHCM must be flashed with the vehicle's specific VIN using GM Service Programming System (SPS). Immediately following programming, a Transmission Adaptive Values Learn (Fast Learn) must be performed using a GM-compatible scan tool to calibrate solenoids to clutch volumes. While Arm 2 notes a full VIN-reflash is not always strictly mandatory when swapping a used unit with its original TEHCM, both arms agree that the Fast Learn is mandatory and a full flash is highly recommended to prevent immediate clutch damage and resolve shift quality issues. Cautious choice: full programming is required.

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

• Torque Converter Seating: Must be rotated and clicked inward three distinct times to fully engage the fluid pump. Failure to seat it fully will crack the internal pump gear upon bolting to the engine, destroying the transmission.
• No Dipstick Fluid Fill Procedure: Fluid level must be checked via the side check plug at operating temperature (185°F to 203°F) with the engine running and vehicle level. Checking cold or engine off causes severe underfilling.
• Engine Dowel Pins: Ensure alignment dowel pins are present in the engine block to prevent high-speed vibration, axle seal leaks, and pump failure.
• AWD Transfer Case (PTU) Splines: Clean and apply high-quality water-resistant grease to the splines before mating to prevent binding.
• TEHCM Generation Compatibility: The 2015 model uses a Gen II TEHCM, which is not interchangeable with pre-2012 Gen I units.

Easy to get right once you know them:

• Buying an internal filter expecting a standard pan-drop service (the 6T45 filter is internal and requires splitting the case to replace).
• Skipping the VIN programming and expecting plug-and-play operation (causes no-start or limp mode).
• Failing to perform the Fast Learn adaptive reset (causes immediate harsh shifting and premature clutch wear).
• Guessing the fluid level due to the lack of a dipstick.
• Reusing the old torque converter or failing to flush the cooler lines, which pumps metal shavings from the failed unit into the replacement transmission.
• Ordering a 2.4L transmission for a 3.6L V6 vehicle, or a FWD version for an AWD vehicle.

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: