A/C PAG Oil

[majorasshole]

I found a leak in my condensor, so I got my condenser yesterday in the mail, so I went down to my Auto parts store to pick up some PAG oil to add to the system and they had 3 types, PAG 46, 100 and 150. I asked them what I should use and they told me I have to call my dealer. I called 3 different Chevy dealers trying to find out what I should use and they told me they sell their own proprietary PAG oil and there is no weight and of course they don’t have it in stock and they have to special order it and will take 3 weeks to get it. I also need 525 viscosity mineral oil to lubricate the o-rings which of course, same deal. Can anyone advise if you know which one I should use? I have an ’01 chevy monte carlo.

Thanks

Topic

[Marc Robertson]

PAG 150 for the 2001 Chevrolet Monty Carlo.

[spelunkerd]

Another tricky thing with this is the ‘how much’ question. It seems that guys just put in a little, unless they are recharging a new system where they can be more exacting. Any advice?

[Marc Robertson]

The typical rule of thumb for automotive AC units is about 1-2 oz per component replaced except the compressor. Then you would measure the amount that is in the unit and replace it. The whole system will typically have about 8-10 oz in it.

Of course, if there are specifications for the particular system available, go with those.

Just be sure to use PAG with automotive and not POE or mineral oil. I made the mistake of using POE once because it is what r134a hermetically sealed systems use, automotive uses PAG.

[John B Kobberstad]

Invest in a good Factory Service Manual. It will tell you what and how much you need. Every component in the system accounts for a part of the total needed. You replace it you add the appropriate amount of OIL. Call the manufacturer of the compressor that you have to get info on what PAG OIL viscosity they use in that compressor. I called Denso to find that in my compressor they use PAG 46 for my 1996 Neon. I would not mix OIL use the same viscosity oil. The number after PAG is the viscosity. Just use a dab of whatever PAG oil you use, to lubricate the O rings. Since your system has probably lost all its refrigerant you may want to just do a flush and remove all the possible contaminants in the system and fill with all new oil and refrigerant and also replace all the O rings and the S valves. That way you shouldn’t have to service it again soon and no moisture on the inside of the windows in the winter. If you don’t have all the proper equipment needed to do the job, manifold gages, vacuum pump, etc take it in and have it serviced. I guess that Chevy dealer won’t be working on A/C if they don’t have the OIL

[EricTheCarGuy]

+1 the service manual will have the amount of oil listed for the component replaced.

[Author]

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