since your selling it, and you want air first, I say 2 choices.

1- convert to 134a= full system flush, replace exp valve, drier, orings, add ester oil and have a shop vac and charge it. or get a vac pump and charge it w/ the cans from the mcparts.

or do the same thing and charge it with r12. there are still shops that do r 12 work, you may need to spend an hour on the phone. r 12 is about 4?x more $$ than 134a, so the cost to charge it will be more, you can get a quote per pound on the phone.

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1984 123.193 372,xxx miles, room for Seven.

1999 Dodge Durango Cummins 4BTAA 47RE 5k lb 4x4 getting 25+mpgs, room for Seven.