20 Most Recent 2008 GMC Sierra 2500HD 2WD Questions & Answers

Same for both doors? If not, I'd check the switch(s) on the drivers door (may be more than one), or may be just one that has multiple contacts and the ones for the lights may be faulty.

2008 GMC Sierra... | Answered on Jul 01, 2017

1. Loosen only, do not remove, the lower outside hidden headlamp bolt (2). 2. Depress the housing support tab with a flat-bladed tool downward in order to release the headlamp assembly from the support. 3. Pull the lamp assembly slightly forward to access the electrical connection. 4. Disconnect the forward lamp harness main electrical connector from the headlamp harness.
Headlamp Screws (Qty: 2)
1 Caution: Refer to Fastener Caution .
6 Nm (53 lb in)
O Headlamp Screw (Hidden)
6 Nm (53 lb in)
3 Headlamp Housing Support

Preliminary Procedure Remove Healamp
Remove either the LF or RF headlamp assembly. Refer to Headlamp Replacement (Chevrolet) Headlamp Replacement (GMC HD)
Headlamp Replacement (HD Diesel).
Headlamp Bulb (Hi)
Warning: Refer to Haiogen Bulb Warning .
Tip: Rotate the bulb socket a quarter turn counterclockwise and remove the bulb from the headlamp.
Headlamp Bulb (Lo)
Tip: Rotate the bulb socket a quarter turn counterclockwise and remove the bulb from the headlamp.

Need more come to https://www.autorepairhelp.us

change-headlight-bulb-2009-gmc-1pzbcmqursjjtd0qcfo11o2t-2-0.png change-headlight-bulb-2009-gmc-1pzbcmqursjjtd0qcfo11o2t-2-1.png

2008 GMC Sierra... | Answered on Jan 10, 2015

Your transmission computer is telling the transmission that the load for that gear is incorrect and will automatically put the transmission in the gear that will not overload your engine. Most of the time when you are going up hill the transmission will do the same. It is just trying to save you an engine rebuild.

2008 GMC Sierra... | Answered on Apr 25, 2014

Take the connectors off and flush with lots of hot water to remove all acids. Then reassemble and tighten properly using plenty of acid free grease/ grease for electrical coonectors.

2008 GMC Sierra... | Answered on Dec 16, 2013

Check for power at the socket. If you have power there bulb is not making good contact.

2008 GMC Sierra... | Answered on Nov 30, 2013

there is an adjustment screw on the headlight bucket

2008 GMC Sierra... | Answered on Sep 02, 2013


2008 GMC Sierra... | Answered on Feb 22, 2013

You have to remove the air intake filter and then kind of reach around up in there to change it. It can be done, but is a lot of work. On the duramax, it is even harder to do the driver side because of the dual batteries. You have to remove the battery, then the battery seat plate, and undo the winshield washer fluid tank and lean it forward. Then you can just sort of reach in and change both headlights. A very big pain to change a couple of headlights, but if you want HID's.... for the average person, changing a headlight now means a trip to that garage.

2008 GMC Sierra... | Answered on Jan 06, 2013

1st number is tread width (mm)265
r =speed rating
2nd is wheel size, in inches 16
the rule of thumb re tread width, is the tread should not exceed the inner wheel width,measured inside the wheel/tyre sealing area by more then 20mm.
otherwise car will tend to sway when steered for moose test.so check your wheels first...
r rating only good upto 100 mph intermitently...

2008 GMC Sierra... | Answered on Nov 30, 2012

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