[jlbrock63]

I'm finding the climate control on '18-'19 and newer doesn't work like I think it should. On a hot day with a/c going, the fan starts slowing down within minutes of starting up, and cab never cools down like it should. With temp set at 72, start off on a trip and cab is 130 degrees. After two hours, the cab is still above 90 degrees. Fan has slowed way down, and air coming out of vents is in the high 50's. Basically the same thing when it's cold and cab needs to warm up. Takes forever to get warm. Dealer has had my truck for over two months and still has no answers. Doors also rattle when going over bumps with rear wheels. They have no ideas. Bumps aren't that big.

 

[freonpushr]

Do you have dual climate controls? Are you using the 'Auto' setting or have you tried using max setting and higher fan speed?
With mine in 'Auto' setting, doesn't take long for the fan speed to drop a lot lower, and to keep my cab cooler on a 99+ degree day, I run my fan speed up higher. Your 50's supply air temp seems a little high though, unless it's on 'Auto' and not re-circulate.

 

[GBSierraSLE]

2 months at the dealer for this?

Have you put a scanner on it to check-out the HVAC system operation? Have you put gauges on it to check the A/C charge? Is your refrigerant low causing your evaporator core to freeze-up? Have you driven another truck to see if it operates in the same manner?

I do like freonpushr and just override it with the fan speed if needed in my truck.

 

[Farmguy]

There is also an 'auto fan speed' setting in the personalization menus. (Climate and Air Quality section)

Auto Fan Speed
This feature will set the auto fan speed.
Select Low, Medium, or High.

Without checking, I think I have it on medium.

I usually leave the system set to auto (and sync with the passenger side).
I open windows for a minute or two when starting out if the truck has been baking in the sun and all inside surfaces are stupid hot.
If (perhaps do to sun angle/direction) I find the cab too hot (or cold) I will adjust the temp up or down as necessary. Sometimes this will result in the fan speed (in auto) changing until it has the temp closer to the setting.
Sometimes this means that the passenger needs/wants to have a different temp setting on that side.

Make sure the sensor on the top of dash near the windshield isn't covered.

If it's putting out 50F air, it certainly sees like it is an airflow / airflow setting issue.

 

[jlbrock63]

Do you have dual climate controls? Are you using the 'Auto' setting or have you tried using max setting and higher fan speed?
With mine in 'Auto' setting, doesn't take long for the fan speed to drop a lot lower, and to keep my cab cooler on a 99+ degree day, I run my fan speed up higher. Your 50's supply air temp seems a little high though, unless it's on 'Auto' and not re-circulate.

My complaint is that the auto climate control doesn't work correctly. Comparing it to every other GM vehicle I have owned, this is the only one that it doesn't perform like it should. If I have it on auto and the temp set at 72, the truck should cool down to 72. It won't. The cab could be 130 degrees, and instead of it cranking out the cold air until it cools down somewhat, the fan starts slowing down after a couple of minutes after starting up. Never cools down like it should.

 

[jlbrock63]

The service manager took me for a ride in a new 2022, and it operates exactly the same way. Earlier on, checked out a 2021, and it was the same. Just a bad design. Fan speed in the settings is on high. Finally picked up my truck yesterday with no resolve. 11 weeks it sat there. I even called GM to see what could be done, and the end result was "try another dealer or see about trading it for a newer one", and "we can't force the dealers to do anything. It's up to them". I came uncorked on the woman and got disconnected. I've bought a lot of GM vehicles over the years.... And this might be the last.