1999 GMC Sierra 2500 Repair and Maintenance
A guide to problems, costs, maintenance and repair for your 1999 GMC Sierra 2500
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1999 GMC Sierra 2500 ProblemsImproper HVAC Temperature and/or Air Delivery Due to Failed Mode Door Actuator
One or more heater & AC (HVAC) temperature and/or air delivery mode door actuator may fail, resulting in improper temperature or air delivery. If this occurs, fault code(s) should be stored in the HVAC control module which should assist in diagnoses.
Illumination of the Check Engine Light can be caused by a loose or worn gas cap.
The spark plugs should be replaced every 100,000 miles. Our technicians recommend replacing the spark plug wires also at this time.
1999 GMC Sierra 2500 Questionswhen i refilled the transfer case I am hearing a whistle noise is that normal? (1 answer)
my transfer case was not going into gears right with my 4x4 gm sierra 2500 1999 model. i refilled it with the transfer oil. but i am hearing a whistle noise, it is shifting now and not jumping like the emergency brake is on..do you know what the whistle noise could be???? I am stuck in the mounta...
how can you check to see if the transfer case for my 4x4 needs fluid
I replaced all the brake lines with Cunifer then bled them at the wheels. The one that goes from the control box (under cab) to rear wheels is leaking. It is screwed in fully and tight but when pressure is applied fluid comes out around the line/fitting. I flared them all the same but none of th...