Transmission Assembly for 2016-2021 Buick & Chevrolet • Encore, Trax
Product Notes Read before buying
This is an All-Wheel Drive (AWD) transmission. It will not fit Front-Wheel Drive (FWD) models. Please verify your vehicle is AWD and has the 1.4L LUV engine (8th digit of VIN is 'B') before ordering.
Voice or type your vehicle details and Wrenchy will confirm fitment in seconds.
Vehicle Fitment Guide
This part fits the following vehicles:
| SubmodelSUB- MODEL |
Body Style | Years | Engine | Attributes |
|---|---|---|---|---|
| Base | SUV | 2016 | L4 1.4L Turbo | AWD | Automatic |
| Convenience | SUV | 2016 | L4 1.4L Turbo | AWD | Automatic |
| Leather | SUV | 2016 | L4 1.4L Turbo | AWD | Automatic |
| Premium | SUV | 2016 - 2018 | L4 1.4L Turbo | AWD | Automatic |
| Sport Touring | SUV | 2016 - 2020 | L4 1.4L Turbo | AWD | Automatic |
| Essence | SUV | 2017 - 2020 | L4 1.4L Turbo | AWD | Automatic |
| Preferred | SUV | 2017 - 2021 | L4 1.4L Turbo | AWD | Automatic |
| Preferred II | SUV | 2017 - 2018 | L4 1.4L Turbo | AWD | Automatic |
| 2019 |
| SubmodelSUB- MODEL |
Body Style | Years | Engine | Attributes |
|---|---|---|---|---|
| LS | SUV | 2016 - 2021 | L4 1.4L Turbo | AWD | Automatic |
| LT | SUV | 2016 - 2021 | L4 1.4L Turbo | AWD | Automatic |
| LTZ | SUV | 2016 | L4 1.4L Turbo | AWD | Automatic |
| Premier | SUV | 2017 - 2020 | L4 1.4L Turbo | AWD | Automatic |
| 2018 - 2019 |
Know This Transmission Before You Buy
The research behind our purchase interview — recalls, bulletins and real install economics for this transmission family:
A quick look at your own vehicle makes sure the right transmission shows up:
- Confirm the 8th digit of the VIN is 'B' (1.4L Turbo LUV engine).
- Verify the vehicle is All-Wheel Drive (AWD).
- Locate the Service Parts Identification sticker and confirm RPO code MNK or MH8, and final drive ratio FXH.
- Verify the 4-character broadcast code on the metallic ID tag of the original transmission matches the replacement unit.
What the install really takes — plan and budget with confidence:
Special tools this job needs:
- Engine support fixture
- Transmission jack
- J2534 pass-through programming tool
- Scan tool capable of reading TFT and initiating adaptive relearn
- Subframe alignment tools
Budget for these consumables at install:
- DEXRON-VI Full Synthetic ATF (7.4 to 9.5 quarts for dry fill)
- Torque converter seal
- Axle seals
- Transmission filter and pan gasket kit (filter is internal and requires splitting case if replaced internally, but external service kits exist)
- Dedicated transmission line flushing solvent
What your vehicle’s computers will need after the swap:
What’s involved: VIN-specific programming and TCM Adaptive Relearn
The integrated TEHCM is programmed to the donor vehicle's VIN. It must be reprogrammed using a J2534 pass-through device with GM SPS2 subscription, or the original TEHCM must be swapped into the replacement unit. A Transmission Adaptive Values Learn (Fast Learn) procedure is mandatory post-install using a GM MDI/GDS2 or equivalent professional scan tool.
Pro tips for a smooth first start-up — hand them to whoever does the install:
- Torque Converter Seating: Ensure the converter is fully seated (typically recessed ~1 inch) by rotating it until it drops multiple times. Failure to do so will crack the internal fluid pump upon bolting to the engine.
- Fluid Level Check Temperature: No dipstick is present. Check fluid level via the side check plug only when transmission fluid temperature is strictly between 85°C and 95°C (or 70°C and 80°C depending on specific GM service manual version) with the engine idling and vehicle level.
- AWD Transfer Case (PTU) Alignment: Inspect and replace output shaft seals between transmission and PTU, and lubricate splines with high-pressure grease.
- Cooler Line Flushing: Must thoroughly flush lines to prevent old debris from contaminating the replacement unit and voiding the warranty.
Easy to get right once you know them:
- Ordering the FWD version for an AWD vehicle or vice versa.
- Reusing the old torque converter, which introduces trapped metal debris into the replacement transmission.
- Skipping the TCM Adaptive Relearn procedure, leading to immediate clutch wear and harsh shifting.
- Failing to program the donor VIN, locking the transmission into limp-home mode.
- Improper fluid level checks due to not following the strict temperature-based plug procedure.
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:
🔎 Recommended at install: Inspect the start-stop accumulator to ensure all bolts are present and torqued to specification before installation.
🔎 Recommended at install: Replace wave plate if worn; Gen 2 and Gen 3 designs have largely resolved this issue.
🔎 Recommended at install: Inspect pump cover and replace worn pressure regulator valve to prevent loss of line pressure and clutch burn-up.
🔎 Recommended at install: Check for loose pins in the main connector, loose TCM ground, or wiring harness rubbing against engine block before replacing TEHCM.
🔎 Recommended at install: Replace the driver-side axle seal and inspect the internal differential case axle support bushing for wear.
🔎 Recommended at install: Diagnose torque converter clutch (TCC) or address fluid contamination.
Researched from factory recalls, TSBs and OEM service data (reference unit 400-10156-2136061). Unit-specific details — mileage, condition, warranty, freight — are covered in the checkout interview.
Policies, in plain English.
Shipping & Handling
- Ships by LTL freight on a pallet — a real freight truck, not a parcel van
- Your checkout freight quote covers delivery to your door (liftgate service included for residential addresses)
- The carrier calls ahead to schedule a delivery window — someone must be present to receive it
- Typically palletized and picked up within 2–3 business days; transit time depends on distance
120-Day Warranty
This part includes a 120-day warranty.
- If the part fails within the warranty window, we'll replace it or refund per the coverage terms
- Coverage is parts-only — installation labor is not included
- Warranty covers defects — not installation errors, misuse, or damage after installation
Your pre-purchase interview reviews these exact terms with you before anything is charged.
Returns (30 Days)
We accept returns of uninstalled parts within 30 days of delivery for this part.
- Defective parts: We will replace the part or issue a refund at our discretion
- Programming: "Needs to be programmed to my vehicle" is not a valid return reason. Many modules require dealer programming — we're happy to help connect you with resources if your dealer says it's not programmable
- Return shipping: This part ships by freight (LTL) — the part price is refundable per the terms above, but shipping costs are non-refundable and return freight follows the seller's return terms. Your pre-purchase interview walks through the exact numbers before you buy
- Parts must be returned in original packaging and unmodified condition
- Poorly packaged returns that arrive damaged will not be credited
Damaged in Shipping?
Freight damage is rare — and you're fully protected when you do two things at delivery:
- Inspect before you sign — you're allowed time to look the pallet over while the driver waits
- Write any damage on the delivery receipt before signing — that one line is what makes a freight claim succeed
- Severe damage? Refuse the delivery — it goes back at no cost to you and we make it right
- Photograph the pallet before unwrapping; report concealed damage within 24 hours of delivery
We handle the carrier claim — you just help document it. Your pre-purchase interview walks through this checklist too.
Order Cancellation
Cancel before shipment for a full refund. Once the pallet has been built, a preparation charge may apply — and once the freight carrier picks it up, shipping costs are non-refundable and standard return terms apply. Your pre-purchase interview shows the exact numbers before you pay.
Expert Guides
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Identify the exact GM Hydra-Matic 6T40 AWD variant, learn what causes premature failure, and know exactly what to look for when buying a used replacement unit.
Read Full Guide →Related Trouble Codes (OBD-II)
7 matching guidesIf your scan tool is showing one of these trouble codes, this part is a common fix. Each guide explains the code, how to diagnose it, and exactly what to replace.
Miscellaneous Information
OEM Part Numbers:
General Motors: 19354015, 19354030, 24275778, 24280898, 24280904
Other: 1818265C1C, 6HRW, 6RRW, 7HRW
Fits Years: 2016 2017 2018 2019 2020 2021
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This unit ships with the selling yard's 120-day warranty. Longer plans can be requested during checkout.
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