AC Compressor Replacements

[l008com]

I was trying to find a cheap AC compressor for my truck. $450 is crazy to fix AC when I live in Boston. I only need AC on like 5-10 days a year. I found this one on ebay and it seems good enough and cheap enough, BUT....
It claims it only works with "Envoys" with the 5.3 V8. That must be an uninformed seller though, right? The V8 TB and V8 Envoy must have identical AC Compressors???

https://www.ebay.com/itm/New-A-C-AC...h=item1a38df907e:g:DIoAAOSw--1WtSk4#vi-ilComp

 

[budwich]

go to rockauto and put in your vehicle info and will see a list of possible compressors. I think in most cases, you will find a compressor and dryer for about $250 or less. Anyways, open any of those listed, and check the info... look at the part numbers and compare with the listing on the auction and you will have your answer.

 

[Mooseman]

Although I have never checked, is it the same compressor for shortie and XL/EXT/XUV? The LWB trucks have rear A/C so bigger capacity. I know the orifice tube is different.

 

[m.mcmillen]

Try 1800 radiator and a/c. I have used several of their compressors on cars that the owner didn’t want to spend a lot of money on an older car. So far, I haven’t had an issue.

They sell a lot of China made stuff but also some higher end parts too.

 

[l008com]

rockauto.com has four compressors listed for 5.3 gmc envoy, and all four list compatability with trailblazers and the other clones too. I don't think there is a "gmc only" compressor, so hopefully this works out.

 

[JerryIrons]

Stay away from 4 seasons, twice I bought one, and was sorry both times. I heard immediate whine as soon as they are put in use.

 

[budwich]

Phew!! I just ordered the UAC kit... hope it ends up good.

 

[l008com]

Update: My mechanic tried to install the new compressor yesterday and it did not fit. My compressor has a 2-pin electrical connector but the new one has a 3-pin. Anyone have any thoughts on this? My truck is a 5.3 V8 and it does have automatic climate control, thus according to another thread on another forum, it's supposed to be using the 3 pin compressor. That thread also suggested the extra wire was just a status indicator. So in theory if I can swap the connectors and get the pins right, this new compressor shoudl work just fine in my truck.

Anyone had to deal with any of this before?

 

[budwich]

was your truck "modded" with by adding the auto climate control? The status indicator wire goes to the PCM, I think... so if your "modded" truck was ACing fine, connecting only 2 of the wires that operate the clutch, should work.

 

[l008com]

I got the truck with 110K on it. Everything looks stock but who really knows what happened in it's previous life.

That said, i've looked up my compressor on every parts website I can think of and they all show me a 3 pin compressor. Even if they 'modded' in the climate control, they wouldn't also swap in a 2 pin compressor, it just doesn't make sense. Is there an official GM website I can look up my VIN on for parts? I'll see if it gives a different result than the others.

 

[budwich]

hmmm.... there are vin look up site to find out original equipment spec... but they are usually a pay site.... although some may have access that they are willing to "share". My next guess would be pull the electrical schematics. Further, my 2008 4.2 had its compressor replaced recently, and I see that the clutch connector only has two wires. I have to check the engine compartment to see what's up with the new as the garage didn't indicate there was any install issue.

A quick check of the GM service manual shows only two wires to the compressor and no mention of a difference between engine types.

 

[l008com]

If you look up your 2008 or my 2008 on most parts sites, it will show you a 3 pin compressor. It's almost enough to make you say screw it and save the gas.

 

[budwich]

if you look at this thread https://gmtnation.com/forums/threads/ac-compressor-clutch-does-not-engage.18876/
one the first page, there is the pdf of schematic for a 2003 which shows the three wires.

I can't readily see the connector on my truck but is appears to be connected accordingly as I don't see any splicing .... but perhaps there is splicing at the compressor. I don't recall when I got the kit from rockauto whether the box included another connector that could be spliced in place of the existing one. Note at rockauto, the GM compressor picture clearly shows a 2 wire connector at the compressor... while other compressors in the list don't really provide a good view of the connector.

A quick look at one auction in ebay shows a "three wire" compressor BUT in the list of compatible trucks, it doesn't show a 2008 4.2... just the v8's. I am thinking that the non-oem guys got the compatibility wrong.

 

[budwich]

I see from the gm si, that the schematic change for 2008 and 2009. Basically, as you know already that the third wire is a "status wire" going to the HVAC control module which you don't have so it doesn't matter. The 2 wires that energize the clutch are the only 2 you need. I would take the connector off the old compressor and splice it into the new one.

further, looking at rockauto again for the 5.3... four seasons picture of the compressor shows two connectors (I think), one 2 pin and one 3 pin so they look like they can be either.