richieracket said:
just going to pass along some info--please set the torches on stun only.
Have an 02' Jetta tdi here with tons of metal in the pan and bad reverse, only 81k. So i'm calling all the suppliers and shops i can getting prices and info on a reman. 3 separate suppliers have told me Pentosian IS the problem. They have a bulletin from an independent lab stating pentosian does not respond well under superheated conditions and toasts the trans, thus creating the abundant premature trans failures. Two have told me they will rebuild and refill with only a reputalbe synthetic fluid, and will not use pentosin even if i supply it. It will void their warranty. They insist they have been implementing this procedure for years with no adverse affects and no returning transmissions.
Let the execution begin.
To echo ScorpionBoy, most interesting. I wonder who this lab is, and how it was that they came to investigate the VW ATF? I also wonder if any other labs have verified their claims, or if they're the "lone wolf".
Perhaps the issue isn't the fluid, but rather the mechanism by which the transmission is cooled - if the "superheated" condition didn't occur, perhaps the VW juice would be okay.
Of course, if memory serves the 01M 4-spd on MK4 vehicles is plumbed into the engine coolant system, instead of the more traditional way where there's a separate trans. fluid cooler in the radiator. I can't imagine how you could run an auxilliary transmission cooler without overcooling the engine (which usually isn't good for the engine). This would also suggest that if you were to have a severe engine overheating condition, the tranny could end up getting cooked as well (collateral damage).
I always thought it was interesting how VW chose to deal with transmission cooling on the MK4s, but until you posted this, I never really thought much about the implications in terms of heat.
Rob
Rob