GM LSx truck A/C belt installing later version

[wirelessF]

In later model Gen IV LS engine trucks (before 2013) GM removed the 4 rib serp belt/tensioner system for the A/C compressor to a stretch fit belt only. This gets rid of the tensioner allowing the tight fit of the belt to provide tension. The GenIII and GenIV uses the same compressor and pulley sizes so this is a cheaper way to replace the A/C belt without buying a new tensioner. You will need to buy the stretch fit belt install tool.

Tools needed:

3/8" socket wrench
Short extension
15mm deep well socket
24mm socket
Stretch-fit belt install tool

NAPA part numbers for the belt and stretch fit tool:

Remove the 6rib belt via the 15mm bolt on the tensioner turning clockwise. Then remove the 4rib belt using the 3/8" end of the socket wrench.

Then remove the two 15mm bolts holding the A/C belt tensioner.

Position the new belt by looping it behind the crank pulley then hook the belt onto the compressor pulley.

Then take the install tool, grasp the belt on top of the install tool and pre-tension/wrap it around the top and behind of the crank pulley so the tool stays in place.

Then use the 24mm socket and wrench to manually turn the crank to fully seat the belt onto the pulley. Then reinstall 6 rib belt and all done.

 

[Shannow]

Nice write-up, thanks.

 

[DoubleWasp]

What is service life like between the stretch-fit and a standard belt supported by an automatic tensioner?

 

[SteveSRT8]

In our fleet the older tensioner style AC belts wear very well. But the tensioner itself is problematic after 100k miles. The belts seem to last a very long time IME, at least as long as the serpentine...

 

[EvanD]

I am gonna try this next. Thank you for the info

 

[Colt45ws]

Seems like a good idea. Modern EPDM belts last practically forever, its just the pullies and stuff that wears first. One less thing to go wrong.

 

[SteveSRT8]

Originally Posted By: Colt45ws
Seems like a good idea. Modern EPDM belts last practically forever, its just the pullies and stuff that wears first. One less thing to go wrong.


Yes indeed, this setup puts that tensioner right near the ground so it gets water and debris in it constantly. We have never broken the belt on these, it's always the tensioner that goes. All our newer trucks use no tensioner...

 

[wirelessF]

Forgot to add this but while turning the crank pulley use your other hand under the A/C pulley to align the belt as the belt wraps under the crank pulley. As the bottom of the belt wraps around the crank pulley, the belt might become misaligned as it seats into place.

What you didn't see in the pics are two belts that I messed up. These belts can't be easily removed unless you have the Lisle Stretch Belt Installer/Remover combo tool which might come in handy if working on engines with stretch belts.

 

[Colt45ws]

Can you unbolt the compressor and let it fall off, or is that more trouble than its worth?

 

[Shannow]

Originally Posted By: wirelessF
What you didn't see in the pics are two belts that I messed up. These belts can't be easily removed unless you have the Lisle Stretch Belt Installer/Remover combo tool which might come in handy if working on engines with stretch belts.


Since you just mentioned it I started looking there's a NAPA one as well.

I just did the belt on my Nissan, and even 'though it's tensioned, a tool like that would be handy, I had to unbolt the alternator, move it full travel, and still swear like a sailor to get the belt on.

The NAPA or Lisle one would be sweet...Lisle one less then $25 on ebay...PLUS $70 pandH to Australia.

 

[TXCarGeek]

Old thread here, but I have an '08 Silverado that is still using the tension pulley for the AC belt. Need to replace it and got to wondering about using the stretch belt....came across this thread with delight!

Is there certainty that the compressors are the same? Looking at Rockauto, the compressors seem to change around the time GM switched to the stretch belt. Would there be any difference in the bearings between compressors using a tensioner and compressors using a stretch belt?

I want to switch to the stretch belt but I would hate to fry the bearings on my compressor from too much tension.

 

[Tomioka]

Old thread here, but I have an '08 Silverado that is still using the tension pulley for the AC belt. Need to replace it and got to wondering about using the stretch belt....came across this thread with delight!

Is there certainty that the compressors are the same? Looking at Rockauto, the compressors seem to change around the time GM switched to the stretch belt. Would there be any difference in the bearings between compressors using a tensioner and compressors using a stretch belt?

I want to switch to the stretch belt but I would hate to fry the bearings on my compressor from too much tension.

All I know is that they both use the Denso 10S20F style compressor so there shouldn't be any change in the compressor size or how it mounts to the engine. Not sure about the pulley bearing between the two but the bearing is super common for Denso compressors and is easily serviceable if they were to fail (and fail a lot.)

If you want to go with an OEM stretch belt the part number is 19210691. It comes with the belt and installation tool included to install the belt.

 

[TXCarGeek]

All I know is that they both use the Denso 10S20F style compressor so there shouldn't be any change in the compressor size or how it mounts to the engine. Not sure about the pulley bearing between the two but the bearing is super common for Denso compressors and is easily serviceable if they were to fail (and fail a lot.)

If you want to go with an OEM stretch belt the part number is 19210691. It comes with the belt and installation tool included to install the belt.

I think I've seen you post about switching to the stretch belt in another thread...no issues with yours so far? The Continental stretch belt is $18 at autozone. Going to pick that up and give the ziptie trick a go.

 

[Tomioka]

5 years since starting the original thread starter with a previous username...no problems with the stretch belt.

 

[TXCarGeek]

5 years since starting the original thread starter with a previous username...no problems with the stretch belt.

Awesome to hear. I'm glad I decided to look into this. My '08 BMW 550i uses a stretch belt for the A/C compressor and I figured I would look to see if GM ever switched to a stretch belt on their trucks...cool that they did and that folks have switched over to it on older trucks.