There is no set time or mileage at which a transmission will fail. There are just too many variables. How it's driven, city, highway, and how well it is maintained.

If it is still working normally, keep it serviced frequently and keep going down the road. If it ain't broke, don't fix it.

The main destroyer of a/t's is heat. For every 10 degrees above normal fluid temp the life of the fluid is cut in half. The fluid temp is not determined solely by ambient. Fluid temp will increase a little in stop & go driving, and a LOT when towing.

Hope this helps.

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2001 SLK 320 six speed manual
2014 Porsche Cayenne six speed manual

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