PennSilverTaco's "Perfect 5-Lug Regular Cab" Build, Aspergers, and General BS MegaThread!

Sounds like the compressor. The clutch locks up and turns the compressor when the AC is on. When it's off, the the AC pulley acts like an idler and does nothing. It just sits there and free spins. I'd have it replaced sooner than later. If the compressor locks up, it can throw the belt. Shredded belt can wipe out other things.

 

I'm most concerned about not having A/C in July!

 

I'd run with the windows down until it's fixed.
Walking sucks........

If you throw the belt, the water pump and alternator wont work. You'll be walking for sure then.

 

Well the thing is, it actually seems to work better with the air on. At least the clutch is spinning with the air on...

 

That too but having thrown a belt before best case you have no steering and alternator either..

 

Will throwing the belt ruin the engine?

 

In and of itself not having the belt won't ruin things, as long as you stop it in short order so you don't overheat.

That said if the belt snaps loose and whips around, all bets are off.

 

Luckily, I'm not doing a lot of driving, but I seriously feel like it's safer with the A/C on...

 

On another note, I drove it without an alternator once...

 

You said above,

How does it run better if it's shaking with the AC on?

 

You can until you have about 9v left in the battery.
Newer vehicles anything in the low 11v and modules start turning off. All bets are off on newer cars/trucks.

 

Because at least the clutch is spinning with the air on. If the clutch is not spinning with the air off, then I feel like that could wear through the belt, and in turn cause it to snap. Should I get the belt replaced AGAIN (even though it was just replaced a couple weeks ago), just in case this has caused premature wear?

 

The clutch is NOT supposed to spin with the AC OFF.
Only the pulley will spin. The clutch is on the FRONT of the pulley.
So what you are seeing when looking at the AC compressor is not the pulley. It's the clutch.
If your pulley was not spinning, we wouldn't be having this conversation. You'd be without a truck. It would be at the shop now.

 

It definitely seems like something on the compressor isn't spinning that should be spinning. What the hell else could be causing this? Why does the truck whine and moan when the A/C is off?

 

Here is a decent video on what the AC clutch does
https://youtu.be/PErA_sFcTHA?si=grwV-tj38UhwP-cB

 

I swear that the compressor pulley is not spinning...

 

@TnShooter

Why does the truck whine when the A/C isn't on?

 

If the compressor pulley isn’t spinning, you’ll smell burning belt.
And you won’t have a belt in about 1 min or less.

I’ve never seen an AC pulley lockup. I’ve only seen the compressor lock up.
The compressor always goes before the pulley bearings.

 

And why does the truck not whine when it is in park or neutral?

 

Could just be how the compressor is failing.
When the compressor is on, the load on the shaft is greater.
This can dampen the noise and vibrations. But it’s short lived. As the compressor usually fails shortly after.

The AC will also add load to all the other pulleys on the engine too.
Maybe it’s another pulley?
I’d take the belt off and spin all the pulleys.

Your mechanic will know what it is, or have a good idea.