gotta flat?

push the winter drive button and see what it does. if it drives fine when starting in third you're probably grinding 1st gear. check the tranny fluid (while running)?

dunno, i'm by no means and expert or heck even half-way edumacated about the matter, but usually when someone new to VXing has problems, it's just because they just changed fluids incorrectly. Our trannies are very sensitive to fluid level...

i'm sure you'll find better help than this - a lot of folks on this board are QUITE knowledgeable on our trucks. might help if you elaborated on the shaking and grinding though.

-scoob