[PonchoV8]

On my pickup Rock Auto lists two compressor with component kits. What's the diff in the two compressors?

GPD Part # 9612768 Compressor Kit
HT6; 6 Gv; CK Classic

$158.79

GPD Part # 9611641 Compressor Kit
H6; 6 Gv; CK Classic

$195.79

[salem1912]

One has a T in it

Anyway found this on the S-10 site it may help.

Re: A/C compressor advice.

If you're going to replace the compressor outright, cross reference OE part numbers 1136519 or 1136521. The HT6 is the only compressor used that year but comes with two different clutch options with a 4" and 5" pulley. Look at the RPO codes in your glove box. If you have code ZN4, you need a compressor with OE part number 1136521 and 4" pulley. You'll need part number 1136519 without RPO code ZN4 and that will have the 5" pulley. As much as I love rock auto, you may want to consider amazon dot com instead if there isn't a discount code for rock auto. I found them to be very competitively priced and no shipping charges in many cases. I've been able to use a 5% discount code with all my purchases lately. It may be enough to just stick with rock auto. Plenty of the aftermarket companies use similar or same part numbers and most that I've seen will use the 4Seasons part numbers. For the HT6 compressors, 4S uses the following:
58950 - New compressor without core charge, crosses to 1136519
57950 - Remanufactured compressor with core charge, crosses to 1136519
58947 - New compressor without core charge, crosses to 1136521
57947 - Remanufactured compressor with core charge, crosses to 1136521

The 4S compressors run anywhere between $160-$225 +/- a few bucks on rock auto and amazon.

Some say good things about the Sanden replacement compressors for the HT6. What I've read is that they've eliminated all the faults of the HT6 with their own designs. The most particular fault being the belly leak at the middle seam of the compressor case. I have seen the compressor and it wont look like your OE compressor, but should bolt in just fine. The only place I've seen them available is on eBay so you've probably already seen what I'm talking about. Regardless of which compressor you choose, remember that you'll need to buy a new accumulator and orifice tube with the new compressor. You'll probably spend about $20 between both of those parts.

If you're a DIY guy, there are gasket kits for the original compressor available on eBay for $25. You'd at minimum need to change out that center gasket and clean out any corrosion on the lip of the case halves. I'd guess you may just need to separate the drive plate off and clean the surface rust with a wire wheel. Put it back together and set the air gap correctly and you might be back in business. I thought I was going to be able to salvage my compressor but it turned out some steel plates on the faces of the pistons shattered and chewed up the cylinders.

[PonchoV8]

Thanks. That could've been an issue if the wrong one was bought. No ZN4 code on mine. I wonder if the only diff is probably the pulley size?

Rock has the Sanden brand. I'm going with a new one (instead of reman), since this has leaked from the day I bought it and gotten worse. I got a lot of yrs and it's at 239K miles. I'm not a fan of the GM stock compressors. I've had 3 of these era of GM trucks and all had the same leaking A/C problems.

Looks like mine is the 5" version. I'm going with new dryer, expansion and orifice tube. I don't want to do it twice.

[PonchoV8]

Take a look at this pic. See all the oil covering the center of the compressor and all the way down the hose going to the condenser. This system has leaked (but worked with recharge) since 2006. The oil has been accumulating all that time.

Is this normal for compressor leakage or would you think this is hose leakage?