Often air conditioners are judged by the difference between the ambient air and their discharge.

If I remember correctly 30 - 40 degree drop is pretty good, because the ambient air gets cooler as time goes by.

I just tested my '95 850 and got a difference of 40 degrees. When my dealer tested it, the technician recorded 37 degrees. I was told that it passed, but I did not ask what their guidelines were. (After reading posts at brickboard for several months, I suspect that for many dealers, the standard is whatever they think the customer will accept!) BTW using a drop of 35 degrees getting a reading of 37 would be a reasonable number in a garage that is kept around 65-70 degrees.

You could test a loaner or take one of the dealer's new or used cars for a test drive and see how your car compares to the dealer's.

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2 8s & 2 7s 600,000 miles total