A/C Compressor Issues

[Ragingsoul]

Year: 04
Make: Chevy
Model: Tahoe LT
Engine Size: 5.3 V8 Vin: Z
Refrigerant Type: R134
Country of Origin: United States

I am getting ready to change out my a/c compressor, accumulator, orifice and o'rings. I have the Denso 10S20F a/c compressor. In the information that I have read it comes with 1.4 oz. (40ml) already in the unit. But I ma confused on whether I need to add more oil when I go to change it out. I have read that I am suppose to measure how much oil is drained and I know that on the old compressor I found a puddle of oil under the vehicle. So how do I determine how much more oil I would need?

Thank you for any and all help.

[JohnHere]

The specs that I have for 2003-2006 Tahoe, all engines, are as follows:

Config. 1: Without rear A/C, 25.5 ounces R-134a, 8.0 ounces PAG-46.
Config. 2: With rear A/C, 43.0 ounces R-134a, 11.0 ounces PAG-46.

A little guesswork comes into play here. But if you have Config. 1, you probably already have about 1-1/2 ounces each of PAG-46 remaining in the condenser, evaporator, and lines, leaving about 5 ounces to add elsewhere. I would drain the compressor and add 3-1/2 ounces to it and 1-1/2 ounces to the new accumulator.

If you have Config. 2, you probably already have about 1-1/2 ounces each of PAG-46 remaining in the condenser, each of the two evaporators, and lines, leaving about 6-1/2 ounces to add elsewhere. I would drain the compressor and add 4-1/2 ounces to it and 2 ounces to the new accumulator.