"Slug/Clunk" From AC Compressor when Clutch Engaging

Hi there. I've used the search function, and read up on the AC Compressor Noise issue that appears to be common to these trucks. I drive a 2013 SR5 Double Cab with the 4.0 V6...close to 28,000 miles, 1 year & 5 months since purchase.

Is this worthy of a trip to the dealer while under warranty? I'm a parts/service manager for our family business, and realize that AC repair and parts are expensive. There is a violent enough action taking place that I can "feel" a slight shudder through the vehicle accompanied with the sound.

I've made a habit of turning off the AC before shutting the truck down, and the noise continues to show up randomly.

Thanks!

 

My truck has always had that clunk it was bad enough sometimes that it feels like the tranny is dropping in to 1st when stopped.

 

Did you ever bring it to the dealership's attention?

 

On a hot day, with the internal fan on high, watch the compressor as it cycles and see if there is a slipping clutch. If you're getting a distinctive clunk, the compressor may be failing internally, building up mechanical resistance with the clutch failing to turn the compressor for a few seconds.
Regardless, get with the dealer to address it for possible future warranty.

 

Ok I'll make a point of watching for a slipping clutch. Thanks for the heads-up. I will try to take a short video & post it if I can get someone's help today.

 

It's normal (but not exactly ideal). After your a/c system sits unused for a period of time, some of the oil will pool on the input side of the compressor along with some refrigerant that condenses and liquifies. When you first start the compressor after it's sat overnight, this little pool of liquid gets thrown into the compressor. As you may know, liquids don't compress so it causes a strain on the compressor veins as it passes through, making this clunk. Older vehicles were designed with a small reservoir just before the compressor to eliminate this problem, but many manufacturers don't do this anymore as they feel it's an unnecessary added cost.

If you want to avoid this thunk, drive for a while before turning on the a/c to let the engine bay heat up which will cause this little pocket of cooled and condensed liquid to heat up and evaporate.

 

Impressive knowledge. I'm just starting to learn more about HVAC and farm equipment AC system as our company sells orchard tractors that are AC-equipped. Thank you for your input.