What is "414b". I recently bought a case of MacFreeze-supposedly a Freon replacement fluid. Is this the same kind of stuff as 414b? Advertisement says this stuff works better than R134a-more like R12-colder air less load on the compressor-less horsepower loss. Supposedly this stuff is compatible with either R12 or R134a Systems-no compressor oil change neccessary. No mention of "membrane" problems. What is the membrane anyway? There are other competitive products out there like Feeze 12 which is a different formulation. Is this one a problem also?
As for R134 Wal-Mart sells it with a fill tube and pressure gauge for about $25. It is easy to put it in yourself. Comes with instructions, hard to screw-up. Low pressure side schrader fill valve is on the passenger side of the engine near the shock tower. Hose won't connect to the high pressure side-different fitting. See other posts on this forum. Mine was overfilled. Wal-Mart also sells R-134a with stop leak, leak detection die and system cleaner. No license needed. Remember R-12 and R134a cannot be mixed.
Rave