Evacuated/Vacuum Pumped A/C System

[mpd13078]

I evacuated / vacuum pumped my '02 TB a/c system because I replaced my accumulator & orifice tube. How much & what viscosity PAG oil should I put back into the system when I recharge it? Still the original compressor.

Thanks.


I forgot to mention TB does have rear air controls if it makes a difference.

 

[Mooseman]

I merged your two posts. Please use the edit button within the 10 minute time limit as per forum rules.

When replacing the accumulator, you need to replace at least 2 oz of oil or the same amount that was poured out of it. Vacuuming it out will not remove oil.

For the viscosity, the manual only gives a part number of 12345923. A reference chart I found says it's equivalent to PAG 150.

 

[mpd13078]

Auto zone pulled up their a/c compressors on the computer & everyone listed to use PAG oil 46.

I found the following information:

http://www.techchoiceparts.com/refrigerant-and-oil-capacities/abcd#chevrolet

General Motors issues Bulletin # 02-01-39-004B replacing PAG 150 oil with a lower viscocity oil. Thus, TechChoice now indicates PAG 46 (P46D) oil for those vehicles.

Thanks for the reply Mooseman.

 

[Mooseman]

Digging a little deeper into this, looks like GM used to use the PAG 150 (12345923) in everything, even those systems that use Sanden compressors that normally use PAG 46 in other vehicles. Discussions in other forums have two schools of thought where the higher viscosity protects the compressor better and the lower viscosity oil has better additives and has been used without issues in other vehicles.

My own experience says that the 150 is good as my 02 TB with 280k km (174k miles) still has the original compressor and working well. I haven't heard of a failed compressor yet on this platform except for issues with the clutch which are repairable. It is possible that GM or Sanden may have found issues when using 150 and decided to switch to 46. Since GM now specifies 46, I'd go with that.