10-Speed Automatic Transmission Assembly for 2019-2020 Chevrolet & GMC

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

• Locate the QR code certification label on the driver's door B-pillar or glovebox RPO sticker to confirm RPO code MQB.
• Confirm the truck is equipped with either the 5.3L V8 (L84) or 6.2L V8 (L87) gas engine.
• Ensure the truck is a 4x4 (Four-Wheel Drive) model.

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

Special tools this job needs:

• Transmission jack
• Heavy-duty jack stands
• Engine support fixture
• GM-compatible scan tool / J2534 pass-through device
• Digital torque wrench
• Fluid transfer pump

Budget for these consumables at install:

• Dexron ULV (Ultra Low Viscosity) Automatic Transmission Fluid ONLY
• New transmission filter (ACDelco TF937 or equivalent)
• New pan gasket
• New front pump/torque converter input shaft seal
• One-time-use transmission filter stretch bolts
• Cooler line flush solvent/machine

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

What’s involved: TUN/PUN Calibration & Service Fast Learn

The 10L80 requires the TCM to be programmed with the specific valve body characterization data (TUN/PUN) of the replacement unit using a GM dealer-level scan tool (such as GM SPS2 / Techline Connect with a J2534 pass-through device). After programming, a Fast Service Relearn (adaptive relearn) must be executed to teach the TCM clutch apply volumes.

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

• Torque Converter Seating: Ensure the torque converter is fully seated onto the input shaft and pump gears (three distinct clicks/clunks). If not fully seated, tightening the bellhousing bolts will shatter the transmission pump gear.
• Exhaust Pipe Clearance: The exhaust crossover pipe runs directly under the transmission pan. Loosen the exhaust flange or use a ratchet strap to pull the exhaust pipe down slightly to gain clearance and avoid damaging the valve body.
• No Dipstick / Bottom Fill: Fluid must be pumped in from underneath, and the level must be checked via the side check-plug while the transmission is running at the exact GM-specified temperature (167°F - 176°F).
• Thermal Bypass Valve (TBV): The TBV is located inside the valve body on gas-powered trucks. If the old transmission overheated or failed, the cooler and bypass valve must be thoroughly hot-flushed or replaced to prevent debris from contaminating the new unit.

Easy to get right once you know them:

• Using the Wrong Fluid: Filling the transmission with Dexron VI or standard synthetic ATF instead of Dexron ULV, which causes immediate clutch chatter, slipping, and complete failure.
• Skipping the TUN/PUN Programming and Relearn: Driving the vehicle immediately without programming the new TUN code and performing the Service Fast Learn, resulting in immediate harsh shifting and clutch damage.
• Failing to Flush the Cooler Lines: Reusing a contaminated cooler and lines, which washes metal debris from the previous failure directly into the new valve body.
• Improper Fluid Level: Underfilling or overfilling due to checking the fluid level without following the exact temperature-based side check-plug procedure.
• Forcing the Bellhousing Bolts: Using the bolts to pull the transmission and engine together when the torque converter is not fully seated, breaking the pump.

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: