A/C Problems

NCMALE76

MEMBER
1999 CHEVROLET TAHOE
V8
4WD
AUTOMATIC
167 MILES

I have the vehicle listed above 5.7L Vortec 4x4. When in stop and go traffic with the A/C on my truck sounds like a leaf blower or a transfer truck when I take off. If I give it half throttle or so it will go away when I get over 35 or so. Doesn't do it at highway speeds at all. If I do a lot of driving in stop and go traffic it gets really bad and the truck has no power at all, and I have to cut off the a/c and drive without it and in a few mins of driving the sound will go away. I am lost on this one and it is driving me crazy! Any ideas?

Tuesday, August 2nd, 2011 AT 9:41 PM

1 Reply

KASEKENNY

MECHANIC
18,907 POSTS

More than likely this is a fan clutch that is staying on high when you turn the A/C on, and it is just vibrating. When you turn the AC on the fan speed is defaulted too high to force the most amount of air over the condenser as possible so more than likely the clutch is just failing, and it sounds like an airplane.

Take a look at these guides that will help with this:

https://www.2carpros.com/articles/fan-clutch-symptoms

https://www.2carpros.com/articles/fan-clutch-removal

Please see the info below from the manual that will give any other details needed.

Please let us know what questions you have. Thanks

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