Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
1989 GMC Forward Control 5.7 K, Automatic, 3L80/M40FACTORY OEM SERVICE PROCEDURE
Overhaul - Gm 117 4-Speed: Application
TRANSMISSION APPLICATION
| Vehicle Application | Transmission Model | |
|---|---|---|
| Blazer & Jimmy (K & V Series, 1983-92 (4WD) | SM465 (M20) | |
| Parcel Van (P Series) 1983-92 | SM465 (M20) | |
| Pickup & Sierra | ||
| 1983-92 (2WD) (C & R Series) | SM465 (M20) | |
| 1983-92 (4WD) (K & V Series) | SM465 (M20) | |
| Suburban | ||
| 1983-92 (2WD) (C & R Series) | SM465 (M20) | |
| 1983-92 (4WD) (K & V Series) | SM465 (M20) | |
Factory Service Tools
Use the Manual With the Right Hardware
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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