How To Change Ac Belt

2500HD 8.1 · January 2, 2009

I need to change the serpentine belt on my 2004 Avalanch 5.3L, so I want to change the AC belt at the same time. I know there is a tension for the serpentine belt, but what is needed to remove the old belt and then tighten the new AC belt?

2000DV4.8 · January 2, 2009

The A/C has its own tensioner pulley. Pull off the serpentine belt first, then take off the A/C belt (I think a 1/4" drive ratchet will fit in the tensioner to pull it out of the way).

2500HD 8.1 · January 2, 2009

Cool. Thanks for the quick answer.

2000DV4.8 · January 2, 2009

No problemo.

CapitalTruck · January 2, 2009

Be sure to change the tensioners while you do this. They can be a sort of headache later (squealing). Cheap insurance.

2500HD 8.1 · January 3, 2009

I'm not one to skimp on maintenance, but is it really necessary to change the belt tensioners when changing the belts? Do these tensioners fail that often?

Impalacat · January 3, 2009

I wouldn't change the tensioner unless it was squealing, I've changed my belts and not the Tens. pulley and I have 101,700 miles, when it starts squealing I'll change it, It wouldn't hurt anything except your wallet.

rjirvine · January 3, 2009

How many miles on the vehicle? I enjoy the belts from the dealer, they are spendy, but high replacement interval, and they have never squeaked on me. I replaced serpentine and ac belt at 100k miles with tensioners. I shouldn't have to worry about them for another 100k miles. In previous trucks, i tried to go cheap on belts and suffered for it. Tip: keep the old belt in your truck for emergencies...(although with a good belt you should never need it). I had a belt cheap belt come apart in east jesus nevada, thank god I had my old one as a spare. I will never go cheap again. I believe the dealer belts are good for 150k miles.

scrapdaddy · January 3, 2009

if you are changing the ac belt change the tensioner to while you are down there.i had a 02 sierra with the 5.3 and if it is anything like that one. it is a real pain in the ass to get to. do it all while you are in there.

Wingnut · January 4, 2009

I wouldn't change either tensioner for two reasons.

1. They're pretty dang easy to get at and replace...Even a roadside repair would take me 20 minutes or so. It's not like you're pulling the front off the motor or something.

2. The tensioner usually doesn't go bad...It's the bearings. New tensioner can cost a LOT of money compared to $5 spent at a fastener store that carries bearings. If you've got the time and a vise (or a little ingenuity), just buy new bearings and press them into the old tensioner.

2500HD 8.1 · January 4, 2009

My Avalanche has 90K miles. I just bought it a few weeks ago, so I like to start fresh and change all the fluids and belts since I have to expect that it was not done by the previous owners. The belts are OK, but they look pretty shiny. No cracks, but for $70 or so I'm going to change them.

I have not had luck with finding the right size belts at local parts stores, so I buy them from GM thru GMpartsdirect.com. The price ends up being similar to Gatorback belts from Autozone, and you get the right size!!! I think I may leave the tensioners for now. They are not squeaking and Autozone stocks them just in case.