I had my W124 recharged last year. The mechanic added (?) R134 to the R12, I think it was. He said that the 2 of them together, get colder than either one can achieve on its own. When he was done, the a/c wasn't great, but better than it'd ever been.

My experience with a/c on 2 different Benz's I owned, is that they simply made (or bought from another manufacturer), a really, really crummy a/c system. It's my estimation, that they're adequate, at best, so long as it doesn't get real hot out. That's why you see a lot of older Benz's, and BMW's, with tinted windows.

I live in the south, and it gets a mite toasty down here. When the temp is 87, like even just a week ago, it can cool the car down within reason after maybe 3 or 4 minutes. But today was 91, plus the car was sitting in the sun for a few hours (the heat builds up in the seats, dash, etc.), and even after 1/2 hour of driving, some of it at 65 mph, with the fan on high, and recirculate on, it never cooled the car down properly.

My guess is that the a/c is simply doing, all it was designed to do,and above a certain temperature, say 90, it just ....can't handle it . Their a/c systems weren't made right to begin with. One Mercedes mechanic told me the problem with their systems is that the (?) evaporator or the coils, are simply too small; it simply can't get rid of too much heat.

1) What's your take on this scenario? Anyone from the south here who has a Benz that cools well in this August heat?

2) Who made the a/c units for Benz? I heard they were American made AC Delco.

3) Where were the a/c's put on the cars? I talked to one guy who swore that any a/c units, were added on to the car when it arrived in the US, zero were put on in the factory, a claim I doubt.

4) What do you all think about that 'new' freon that says something like "13 degrees colder than R12" on the can? Anyone tried it, and is it any good?

1991 300d, 163,000