according to the audi brochures, only the 1990 and 1991 5 speed models have a 4.11:1 final drive ratio. the '91 automatic (3.6l) and '92 and later cars (all automatic, but 4.2l) had final drive ratios listed at 3.73:1. the big engine can handle the 3.73 ratio just fine, but i would stay far away from the '91 automatic with 3.6 and a tall final drive. the slushbox ratios are identical throughout. eliot