For the most part, toe in is a carry over from the bias ply tire days. Not nearly so necessary with radials. I have run a number of cars with zero toe and had excellent tire wear as a result.

My wife had a Mini Cooper that my daughter wrecked. It had about 100,000 miles at the time of the accident and never had any tire wear issues. After the accident it went through a pair of tires so fast I didn't even notice before they were gone. My wife took it to the shop where the work had been done and after setting it up on the machine they said everything was within spec.

I didn't even think of checking toe because I thought something was wrong as a result of the accident. I took it to my own local shop and they said everything was within spec. I asked them if I could go watch the process. The guy set it up on his $30,000 worth of Hunter gear and it was showing significant toe in. He defended himself by showing me the book that indicated that much toe in was within spec. He wasn't very cooperative, so I took it home, got out the jackstand, nail, vise grips and tape measure. The wife and I set it in the driveway and tires lasted seemingly forever after that.

I've had similar situations, although not so drastic with MB's. If you want good tire wear, set it on zero.

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

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