I replaced all the rubber hoses, using better "barrier hose". For the large suction hose, I used "reduced barrier" for a smaller OD. You need to cut the shells off the fittings to re-use, since I don't think they are available. M-B used thick ferrules, but you can get them off w/ a hacksaw, screwdrivers, and vise. If changing to a newish parallel-flow condenser or Sanden compressor, you can use more common O-ring fittings at those ends. If you don't have a ferrule crimper (I do), you can use Oeticker stepless ear clamps (ebay) and perhaps even PEX ferrules from Home Depot for some hose sizes. Download a hose catalog (Gates or Goodyear) and check dimensions. Replace all O-rings with HBNR type (usually green). Fill with oil w/ uV dye so you can find future leaks easier. I used PAO 68 oil which works with all refrigerants and Duracool HC refrigerant. R-134A is a potent greenhouse gas so is being discontinued.

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1984 & 1985 CA 300D's
1964 & 65 Mopar's - Valiant, Dart, Newport
1996 & 2002 Chrysler minivans