I've just started using the AC on my truck recently, and it has a pretty steady lope. It only happens when stopped in gear at idle. It's a bone stock '96 3/4 ton 4x4 automatic with about 118,500 miles. Only acts up at idle with the AC on. Any thoughts?

 

Idle might be a little low, should be around 750 in drive with ac on.

 

Thanks for the quick response. I think mine is around 4-500 when the ac is on. I'll try stepping it up.

 

X2 gorms answer.
750-800 is a better idle RPM range to shoot for.