you can use the Walmart stuff, but it is better to use the hoses with the gauges unless you have a sightglass, if you put too much freon in it, it will not cool right You need to buy the R134a conversion kit they sell.In order to add freon. I know, because I have a 91 caprice 9c1.You first need to remove the old freon that's in the system, which is R12. you can take it to any ac place and they will do it for free. next is buying to kit right now it's around 30 something dollars. I did the conversion myself, and the AC blows nice and cold. Also you need to locate the lowside which is located on the passenger side, silver canister. I don't know where is the highside, but it's not nessasary to find it.It's the lowside you need to lok for. Im not sure but i think the highside is on the compressor itself. I hope this help's you. I own a shop and I do NOT know any shop that will do anything for free. If they did they would NOT be in business as it requires money for all the special tools. If you buy the "STUFF" from walmart then we again will NOT service you AC as it has stop leak in it and it will RUIN our $5,000 Machine.
r-12
The average amount of pounds a Chevy Caprice would take is 3 to 4 pounds. Freon is difficult to obtain and you have to know what you are doing to charge a car.
1.58 lb ( 3.50 kg)
Was built for R12, should be converted to R134a
It probably had R12 from the factory, this is now banned.There are "Drop in" replacements available.
Buy a kit a t Wal-Mart or auto parts comes with instructions
It should tell you on the air conditioning unit but it's more than likely R12. I have an '89 Caprice and it takes R12.
On my caprice I know because it was a police car it used R-12 and it can't be bought in stores. Only mechanics are authorized to carry it!
r12
R134
There is only one Freon, and that is R12. R12 Freon came installed in your 1991 Chevy. It may or may not have been changed over to R134 Refrigerant. If not change it over, as the cost of R12 is unbelievably high an is no longer in production.
Where do I put freon in a 2007 chevy impala