I have done quite a bit of flat towing with stick equipped mercedes with no ill effect. I towed my 72 220d to the smokey mountains and back on a tow bar with no ill effect.

Now towing an automatic is a whole different story. If you want to flat tow you better run the engine or unhook the driveshaft.

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.