6-Speed Automatic Transmission Assembly for 2015-2019 Chevrolet & GMC

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

• Verify VIN 8th digit is G (6.0L L96 V8 gas) or B (6.0L LC8 gas/CNG).
• Verify RPO code MYD on the SPID sticker in the glove box.
• Confirm vehicle is 4x4 / 4WD with a front driveshaft and transfer case.
• Verify transmission case tag code is 4DHA, 3DHA, 5DHA, 6DHA, or 7DHA.

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

Special tools this job needs:

• Heavy-duty transmission jack (rated for at least 500 lbs)
• Torque converter depth gauge or straightedge
• Transmission cooler line flushing kit
• GM-compatible J2534 pass-through programming tool (e.g., GM MDI2)
• Professional-grade diagnostic scan tool

Budget for these consumables at install:

• DEXRON-VI Automatic Transmission Fluid (12.4 to 13 quarts for dry fill)
• Transmission Filter & Pan Gasket (GM Genuine Filter Part # 24236517 / ACDelco 24236933, Gasket Part # 24226850)
• Torque Converter Pump Seal (Front Pump Seal)
• Transmission Cooler Line Flush Solvent

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

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

The internal TCM/TEHCM must be programmed with the vehicle's VIN using a J2534 pass-through tool and GM's SPS2 software to prevent immobilizer codes and limp mode. Alternatively, the original functional TEHCM can be swapped. A Service Fast Learn procedure is mandatory post-install.

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

• Torque Converter Seating: Must engage three distinct times (three clicks) and sit at least 1 inch inward from the bellhousing face. Forcing the bolts with an unseated converter will crack the front pump.
• Mandatory Cooler Line Flush: Debris from the previous failure must be completely flushed out to prevent immediate contamination of the replacement unit.
• Upgrade the Thermal Bypass Valve: Replace the original valve with the updated 158F version to prevent overheating.
• Precise Fluid Level Check: Check on level ground at 86F to 122F fluid temperature while idling in Park via the level check plug.
• Bellhousing Dowel Pins: Ensure alignment dowel pins are present and clean on the engine block.

Easy to get right once you know them:

• Skipping the VIN Programming: Assuming the unit is plug-and-play, resulting in a no-crank or limp mode.
• Forcing the Bellhousing Bolts: Drawing the transmission and engine together with bolts when the torque converter is not fully seated, cracking the pump.
• Reusing the Old Torque Converter: Contaminating the replacement transmission with metal debris trapped in the old converter.
• Skipping the Transmission Fast Learn: Failing to run the adaptive relearn, causing harsh shifts and clutch damage.
• Buying the Wrong Drivetrain Version: Purchasing a 4x4 transmission for a 2WD truck.

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: