There is a small motor ( about 3-1/2" to 4" in diameter and about 8" long ) on the upper left hand side ( if your outside looking down at it ). Sit's behind the headlight. What is it ?
Go's on and off while the vehicle is running. makes a lot of noise. I think it might be some kind of pump. It sounds like a compresser when it's running.
Not familiar with your truck, but it sounds like you've described the air conditioning compressor. It'll engage and disengage as necessary.
Thanks ytlas,..... Even if I don't have the AC on ?
Post a picture - there's an "add photo" button in the reply box, that way everyone can be certain of what you are trying to identify.
If it has a pully with a belt on it, it would be the AC compressor. It is the clutch going on and off that you are hearing.
It is the air compressor for the rear air suspension. It inflates the air bags on the rear of the vehicle. This is a self leveling system so when it detects that the suspension is low it turns on the air compressor to inflate the air bags to the correct level. If it 97 coming on a lot, you need to check the lines and suspension for a small air leak
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