Automotive Air Conditioning Information Forum

i'm using the 20-132 bracket set for the sanden comp. i can get just the comp. bracket for the r4 if needed. i'm leary of using a r4 comp. they have a bad rep.

The R4 would go 80,000+ miles around here in a Suburban with dual A/C running limo duty.

What seemed to kill them was either running them with a low charge, or exterior corrosion.

Cheap remans from sketchy sellers made them sound worse than they really were. Add to that the learning curve - in 1995 we were just starting to see serpentine and parallel flow condensers. People were still trying to flush those condensers after a compressor failure. Not realizing the condenser was the primary filter.

Around the same time we heard a lot of talk about Ford compressors & "black death". Axial piston FS10 style compressors failing for "no reason" leaving black goo in the system. Lubrication failures with polymer piston rings and SEC PAG. Lots of learning went on in the early 90's with 134a, condenser & lube changes.

Todays lubricants, better manufacturing tolerances than ever before - and a better understanding of the refrigerant system requirements would make a new R4 an acceptable compressor. It has enough volume for your needs, it is a direct bolt on & is compatible with your existing CCOT system. Your only problem with your system right now is a lack of pumping capacity. An R4 is the most direct bolt on solution.

Use the standard piston R4 with the small diameter serpentine clutch (Ex. 1995 Suburban application) and avoid the "scroll replacement" - china slapped a small scroll in an R4 can and they have a really poor reputation around here.

Again, the R4 does not do well running on a low charge - but neither does ANY other compressor.

The SEC PAG oils of the 1990's were garbage. We ran BVA POE 100 in all of the R4 compressors without any issues. Idling for hours in the 110f heat.

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wow. more good info. thanks again! what would be a good brand for a new r4?

I have not bought a new R4 for a few years. Contact Tim, he will know which supplier has their act together. I buy compressors from him.

Use whatever oil the compressor manufacturer recommends. If it is PAG, make sure it is the DEC variety.

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thanks again.

Original GM R4. Still not the quietest compressor out there. So take notice before ordering.

https://ackits.net/product/14-20189/

Way to go Tim. Actual Delco parts!

No, never going to be the quietest unit. Using the steel can for the refrigerant circuit is good from a thermodynamic standpoint, but it does transmit some cylinder noise. But they got the job done in large vehicles for decades.

bohica2xo wrote:Way to go Tim. Actual Delco parts!

No, never going to be the quietest unit. Using the steel can for the refrigerant circuit is good from a thermodynamic standpoint, but it does transmit some cylinder noise. But they got the job done in large vehicles for decades.

Just making notice these are a little noisy and not defective. People hear a little noise and what to exchange. After sending 2 or 3 units. It gets costly for a non-issue.

Yeah, the NVH department at most automakers should be fired. Liquid filled engine mounts and every other non-functional cost increaser they can find. I heard some whiner complaining recently that he could hear the fuel injectors clicking at idle with the hood up. I told him to trade it for a Nissan Leaf.

New cars are so quiet now that any noise is perceived as "bad". People at car shows wince at the sound of my flat tappet solid lifter cam, when I park next to them.