A/c Compressor Making Noise

leesfeed · February 24, 2011

Hello! I have A 2002 Yukon XL with 152,000 miles with the 5.3 litre. We recently started using the A/C. When the vehicle has been off for a while and you start it up, turn the A/C on, put it in drive and give it gas, there is a loud grinding sound followed by a thud. This only happens when the A/C button is selected to the on position and when the vehicle has been off for a bit. It also only happens from a stop after you give it gas. The A/C blows ice cold. The sound is similar to that of someone grinding gears in a standard transmission followed by a thud. I was told that it may be the compressor clutch going out and that I could get a compressor rebuild kit for it. If so, will I need to take the compressor completely out of the engine compartment to get the clutch assembly off? Thanks for any advice!

leesfeed · February 25, 2011

Today I had my wife press the accelerator pedal while I was under the hood. When the RPM's got to 1500 the A/C compressor sounded like it was about the come apart. The sound was a grinding metallic sound with a high pitch squeal. I actually stepped back at one point because I thought the thing was going to fly out of the engine compartment. Also, when the A/C button in the cab is on the compressor pulls the engine down and makes the entire truck shake as well as the engine. Any ideas on what might be causing this sound? Thanks!

HawkScot · February 25, 2011

Sure sounds like it could be a clutch going out, but I think the clutch may be a symptom, not the root cause. If your compressor is turning that hard, you have other AC problems (probably compressor). The clutch is unable to lockup due to the high load, hence the squealing. You could get a new compressor, complete with new clutch and put it on yourself, but you still would need to evacuate the system and charge it. While it is open, you may want to change a few things, such as the orifice tube (little screen that can get clogged over time) and perhaps the dryer.

Get it checked out at a shop that does AC work.

You might want to unplug the electrical connector on the compressor in the mean time to keep from frying the serpentine belt if the AC gets turned on until it gets fixed.

leesfeed · March 3, 2011

Sure sounds like it could be a clutch going out, but I think the clutch may be a symptom, not the root cause. If your compressor is turning that hard, you have other AC problems (probably compressor). The clutch is unable to lockup due to the high load, hence the squealing. You could get a new compressor, complete with new clutch and put it on yourself, but you still would need to evacuate the system and charge it. While it is open, you may want to change a few things, such as the orifice tube (little screen that can get clogged over time) and perhaps the dryer.

Get it checked out at a shop that does AC work.

You might want to unplug the electrical connector on the compressor in the mean time to keep from frying the serpentine belt if the AC gets turned on until it gets fixed.

You were right! It was the clutch going bad. I bought a brand new compressor with a clutch already on it and changed the expancion valve, belt and tensioner pulley. My mechanic said the pulley had a broken spring and the compressor was about to shut down completely. I got it all changed out now and blowing at 40 degrees! I just had the knock sensors and wiring harness changed last week in it. Now time to replace the oil pan gasket so it will stop leaking on my carport!!