Thanks, Moppie, for your quick reply. The reason I asked, and please excuse my ignorance on the subject, is that my dealer just did a 60,000 mile service on my 1993 manual 5-speed. The following appears on the invoice: "Service Automatic Trans - Z0501" and "ATF pennzoil - 36". A few weeks after the service the clutch began to slip. Was the wrong oil used and could that cause the problems with the clutch? I'm taking the car back in tomorrow. Thanks again for your help.