Can aftermarket wheels cause any damage?

Question

particularly to the transmission or differential? (I have an Audi A4 Quattro). Can I go from a size 17' to a size 19' rim?

Answer 1

It takes a little more torque to pull out with larger wheels- but nothing too significant.  Just go with low profile tires and the end result will be similar size.

Answer 2

No damage. But unless you go with a smaller side wall tire, your speedometer will be off by a few M.P.H.