If your mechanic said your box should handle twice as much power then he is an idiot for saying so unless it is full custom which at $2200 it isn't going to be. That being said he is a LEGEND for doing a rebuild / repair for free labour.
The VW gear sets have been around and getting abuse for over 30 years in most cases so expecting them to hold any sort of power is a big gamble. If you get the gears tested you will find them full of cracks and imperfections. This results in them just letting go for no real reason other than it is their time.
This is not to say you won't get lucky from time to time and have a very long life from a stock gearset.
I have had stock transmissions last many years and I have had rebuilt ones last 10 mins with stock gears. I even had a set tested after the fact and was amazed at how many stress cracks there were.
If you want it to last by fresh gears from someone like Albins and pay the $$$$. Otherwise get the stock ones tested and try and find a good set.
Talk to Dave Buttler (aka Dangerous) for strength options, he is a gearbox guru ..
Brad Wolfsburg Elder
3,764 posts · joined Aug 2002 ·