Birchall
Dick Chown Award 2016
The TDI90's gearbox is different in that some of the ratios are slightly longer, but the basic gearbox is the same. All A2 TDIs use 02J transmissions, which are rated up to 250Nm of torque (184 lbft).
There are plenty of remapped TDI75s that are pushing this limit, and a remapped TDI90 will go beyond. However, the chances of you doing your 'box damage is pretty small.
If you're spinning the engine at the rotational speed where you get peak torque and you then pop the clutch in 1st gear, you could damage that gear's teeth or the bearings, etc. However, that's not a normal thing to do. In normal driving, peak torque will happen when you're already driving, the gearbox is already spinning, etc. As such, there are no sudden impacts. Despite there being a fair number of remapped TDI90s kicking around, no one has ever experienced gearbox issues as a result.
VR6 engines attached to 02J transmissions well exceed the gearbox's rated limits by some margin, but as long as the driver isn't deliberately abusive there shouldn't be an issue.
Cheers,
Tom
Yes, wot he said !!!
Steve B