2008 GMC Sierra 3500 HD Repair and Maintenance
A guide to problems, costs, maintenance and repair for your 2008 GMC Sierra 3500 HD
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2008 GMC Sierra 3500 HD ProblemsReduced Power and Check Engine Light
The GMC Sierra 3500 HD uses a throttle position sensor (TPS) which commonly fails and causes:
- Check engine light illumination
- Reduced Power message
- OBD trouble code P2135
This issue is related to the throttle position sensor, and can be caused by faulty wiring to the TPS, bad connection at the TPS, or a failed TPS.
To correct this issue, the wiring harness, connector, and throttle position sensor must be inspected, tested, and/or replaced. The most common cause is a faulty TPS.
A Loose or worn gas cap may cause Check Engine Light to illuminate.
The spark plugs should be replaced every 100,000 miles. Our technicians recommend replacing the spark plug wires also at this time.
2008 GMC Sierra 3500 HD QuestionsI pull a 16000 lb rv and it keeps overheating on me going up hills or passes (1 answer)
pulling it up like a 6% grade it will overheat and I have to pull over and let it cool down??
when docking trailer, low revving and slow moving steering becomes non-power. Brakes are quite often "soft" even when steering seems fine. Mechanic says rotors are fissured and needs new pads. Pump is leaking. Is this a Hydroboost thing or just steering pump. Is $3400.00 a reasonable pr...
2008 GMC Sierra 3500 HD RecallsFront Passenger Air Bag Defective
In a crash that deploys the passenger front air bag, the inflator of the air bag can rupture, causing metal debris to strike vehicle occupants. Dealers will replace the front passenger air bag inflator free of charge to correct the concern.
If too much current is drawn from the auxiliary battery, the fusible link can melt, causing risk of fire. Dealers will replace the jumper harness with one that includes a 40 amp inline fuse, and provide vehicle owners with supplemental owners manual information free of charge to resolve the problem.
The heated washer module under the hood could overheat due to excessive current draw. Under certain conditions, this could result in an under hood fire. This previous recall attempt in 2008 to repair this concern did not have the expected success. Dealers will now permanently disable and remove the heated washer module to correct this concern. This recall is expected to begin on June 20, 2010.