The items that usually wear out are the oring seals inside the clutch packs. They get abused from high trans temps (when towing) and contaminated oil, but that's it. Keep you're oil changed and your loads light and it shouldn't matter how many times you put it in neutral.
However, racing the engine and throwing it in drive may cause damage to the clutches themselves. I would think a minor blip on the peddle would be ok, but I have never had to do that in my car.
|