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.
2002 GMC C3500 HD 6.5 F, AutomaticFACTORY OEM SERVICE PROCEDURE
Installation Procedure
- Install the injection lines at the pump. Refer to Fuel System Description .
- Uncap the lines and pump fittings.
- Refer to the tags for the correct installation.
- Install the injection lines at the nozzles.
NOTE: Refer to FASTENER NOTICE . - Uncap the lines and the nozzles.
Tighten
Tighten the fittings to 25 N.m (18 lb ft).
- Install the injection line clips at the loom brackets.
- Remove the J 39664 manifold cover set.
- Install the intake manifold. Refer to INTAKE MANIFOLD REPLACEMENT - UPPER and INTAKE MANIFOLD REPLACEMENT - LOWER .
- Install the negative battery cables.
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.