PAG oil capacity question

[Erik]

Hey all. Does anyone know the PAG oil capacity for the AC system when using a remanufactured A6 compressor (Four Seasons) on a R134A system? The system is open, I'm going to replace the compressor, accumulator and orifice tube and I'm going to flush the system. The new compressor says it has 3 ounces in it, but the chart they provide doesn't give me an answer for the overall capacity in our trucks. I have read both 8 ounces and 11 ounces. Does anyone know which is correct? Thanks!

 

[CookieSoup]

im not sure but im interested to find out

 

[Erik]

The best I can tell from the compressor chart, it says 10 ounces of mineral oil for the A6 compressor in vehicles with no rear ac. So I'm gonna go with 10 ounces of PAG - 8 in the compressor and 2 in the accumulator. We'll see how this works out.

 

[75gmck25]

I would not go over 10, although the specs do call for 10.5-11.0. You should be charging with less R134a (usually 75% of R12 charge), so less oil makes sense.

Did you buy an actual A6, or is it one of the new clones (Pro6Ten?). My original A6 died due to the black death, and the rebuilt I got did not last well either. I got a Sanden and brackets from Vintage Air, and had hoses made to adapt them to the old system. It works well, especially now that I've found my leak (high pressure cutoff switch body was slowly leaking).

Bruce

 

[yevgenievich]

Sanden guide has good info on AC system oil capacity and couple of ways to calculate given the size of the AC system. Given a6 compressor I think it would still apply using the upper limit of the allowable fill levels
https://www.gmsquarebody.com/threads/sanden-service-guide.22419/