1991 LS 400 what kind of refrgerant and is available in a rechargeable can
134A is what is out there now. In 91 R12 was still being used, so your system will have to be retro fitted to use the new 134A. That includes evacuating the system and flushing the out the old oil, replacing all of the systems O-rings and adding new 134A compatable oil, installing new fittings, evacuating the system again to make sure there are no system leaks and then recharging with 134A.
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