Jim -

Actually, thats not correct. While the condensers in your vehicles may appear quite similar in appearance, there is a significant difference in their design and construction.

The R-12 system uses the old-style tube and fin condenser whereas the R-134a system uses the parallel flow style of condenser. The PF condenser is superior in cooling performance to the tube and fin design but is more expensive to manufacture and quite difficult to thoroughly flush in the event of a compressor failure.

To the best of my knowledge, M-B factory fitted all '80s and '90s decade USA R-12 equipped vehicles with tube and fin style condensers, with the exception of the '91 350 SDL, which used a PF style condenser (126 830 29 70). This condenser can be used as a replacement for the R-12 condenser 126 830 27 70 by those looking to improve R-12 cooling performance or R-134a refrigerant conversions in W126 vehicles. The 29 70 is equipped with mounts for dual auxiliary fans, which greatly aid AC system performance.