[Ernestowynn]

I have a 2017 ZR2 diesel we purchased new. Now has ~100k on it and we are noticing that there is sometimes a loud whine (I initially thought transmission), but the AC is blowing warm. Then if I shut the truck off and restart, it seems to then go away and the AC works properly. Very random but I’m concerned because it is now out of warranty. Anyone else experience anything like this?

 

[oak1971]

I have a 2017 ZR2 diesel we purchased new. Now has ~100k on it and we are noticing that there is sometimes a loud whine (I initially thought transmission), but the AC is blowing warm. Then if I shut the truck off and restart, it seems to then go away and the AC works properly. Very random but I’m concerned because it is now out of warranty. Anyone else experience anything like this?

I cant't say for certain as I never worked for GM, however I did work for a large corporation in Quality/Reliability at the latter part of my 25 year career as a Lab Tech. A good 85% of the testing we conducted (testing which continued 24/7 until complete) involved what we called "Design Life Testing". There were engineering studies that predicted based on retuned units from consumers just how long a product would last. Our testing in the Lab prior to a new product release and at various intervals during the life of the product, involved determining if the product would perform to specifications to the end of our warranty period. I suspect yet cannot confirm the same is the case in the automotive industry even though I did work in the auto industry for 20 years before moving on.

Short version, most parts are only designed to last long enough to fail on your dime.

 

[Ernestowynn]

Hope your wrong but it’s sure possible. It seems like it’s working or computer/ignition related. Like i said, it works perfectly when working but then other times, it just randomly starts making an external fan whine (quite loud) and seems to be bogged down when this happens). Very strange deal

 

[scarfile]

I have a 2017 ZR2 diesel we purchased new. Now has ~100k on it and we are noticing that there is sometimes a loud whine (I initially thought transmission), but the AC is blowing warm. Then if I shut the truck off and restart, it seems to then go away and the AC works properly. Very random but I’m concerned because it is now out of warranty. Anyone else experience anything like this?

Bearings

 

[Dmax Dan]

Sounds like what my truck is doing at 90k now. Originally, I was worried that I was chasing a blown head gasket or cracked head, but I was miraculously losing coolant which was unrelated. I did have to replace my fan clutch recently. My AC makes noise when slowing down to idle and occasionally when I turn the AC off at idle. I plan to just let it go until it bites the dust and replace it then. Hopefully it will last until my timing belt interval.

 

[Dmax Dan]

I forgot to mention, if your AC is blowing warm and you’re not certain what the issue is, I would rent the combustion gas tester at any auto store, just to rule out head gaskets. With our high compression, combustion gasses are forced into the coolant system, not leaking into the cylinder like in the gassers. Fingers crossed it’s just time for a new AC.

 

[splitley]

I have a 2017 ZR2 diesel we purchased new. Now has ~100k on it and we are noticing that there is sometimes a loud whine (I initially thought transmission), but the AC is blowing warm. Then if I shut the truck off and restart, it seems to then go away and the AC works properly. Very random but I’m concerned because it is now out of warranty. Anyone else experience anything like this?

Yep my 16 Colorado did it while it was still under warranty, chevy dealer said they couldn't diagnose til it stopped working completely, well after a year I took it to a GMC dealer and they fixed it in 1 visit, bad compressor, didn't throw any codes, you need a mechanic not a code reader!

 

[Ernestowynn]

I have a 2017 ZR2 diesel we purchased new. Now has ~100k on it and we are noticing that there is sometimes a loud whine (I initially thought transmission), but the AC is blowing warm. Then if I shut the truck off and restart, it seems to then go away and the AC works properly. Very random but I’m concerned because it is now out of warranty. Anyone else experience anything like this?

More info, this randomly happens and when it does, the temp gauge stops working, ac stops working and loud fan whine. Then if I stop and shut off the engine, restart it goes away but sometimes it is throwing a p0119 ECT sensor? I’m not sure. I ordered a new ect sensor today and will change it out next week. I believe it’s an electrical problem either sensor, thermostat, short in wiring or something. Very random and difficult to pin down cause just yet.

 

[Inacanyon]

Check for wiring chaffing.

hearing the harness on the back of the ac compressor wears through

 

[Ernestowynn]

I’ll check for that. Thanks for the good advice

 

[terryjm1]

My intermittent AC issue recurred on my most recent 1000 mile trip. It always coincides with transition to high heat and humidity climates. In my case, most typically, around the Amarillo, TX / Oklahoma border. Now, I make extra effort to notice it as it begins. As long as I turn off the AC, not the blower, and allow outside air to circulate, after about 10 minutes it returns to normal. However, I have to continue to let In outside air (turn off recirculate) or it returns in short order. For some reason, it is freezing up during these conditions when recirculating inside air.

 

[Roberto V.]

I have a 2017 ZR2 diesel we purchased new. Now has ~100k on it and we are noticing that there is sometimes a loud whine (I initially thought transmission), but the AC is blowing warm. Then if I shut the truck off and restart, it seems to then go away and the AC works properly. Very random but I’m concerned because it is now out of warranty. Anyone else experience anything like this?

Hello! Any news about this? My 2020 2.5 Colorado has 20k miles. I have already changed the compressor, and guess what? The same problem today!
The new compressor only lasted two days.

 

[SFLTruck]

Hello! Any news about this? My 2020 2.5 Colorado has 20k miles. I have already changed the compressor, and guess what? The same problem today!
The new compressor only lasted two days.

Is the compressor locking up?

 

[DieselDrax]

Hello! Any news about this? My 2020 2.5 Colorado has 20k miles. I have already changed the compressor, and guess what? The same problem today!
The new compressor only lasted two days.

Shouldn't all this be covered under warranty?

 

[Roberto V.]

Is the compressor locking up?

I don’t know what You mean lol. But out of the blue th A/C started working again. I really dont know whats the problem

 

[Roberto V.]

Shouldn't all this be covered under warranty?

Ibhave purchased the car in the US and moved it to my country. No warranty can be applied