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.

1982 GMC Magnavan Automatic Trans, Trans Mfr CD 400/M40FACTORY OEM SERVICE PROCEDURE

Transmission Assembly: Remove, Install, and Overhaul

TRANS ID - 250, 250C, 350, 350C

Includes: R&I Transmission Assembly, inspect and replace necessary components and road test.

Applies To	Standard Hours	Skill Level
G3500,RWD	10.1	A
Combination Procedure: FLYWHEEL: Remove & Replace:
	0.3	C
Combination Procedure: TRANSFER CASE ASSEMBLY: Overhaul:
Spicer	2.9	A
Combination Procedure: TRANSFER CASE ASSEMBLY: Replace:
	0.3	C

TRANS ID - 400, 475, 3L80, 3L80HD

Includes: R&I Transmission Assembly, inspect and replace necessary components and road test.

Applies To	Standard Hours	Skill Level
	11.2	A
Combination Procedure: FLYWHEEL: Remove & Replace:
	0.3	C

TRANS ID - 700-R4, 4L60, 4L60E, 4L65E, 4L70E

Includes: R&I Transmission Assembly, inspect and replace necessary components and road test.

Applies To	Note	Standard Hours	Warranty Hours	Skill Level
G3500,RWD		10.2		A

Factory Service Tools

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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.