Volkswagen Group B platform. The Volkswagen Group B platform is a mid-size automobile platform from the Volkswagen Group. It has been used for saloon cars/sedans, estate cars/station wagon, and coupés - under the Volkswagen Passenger Cars, Audi, SEAT and Škoda marques . Volkswagen Group revised the alphanumeric nomenclature used for car
S-line is just some cosmetic changes; depending on the year maybe also some suspension changes. But not driveline changes. The final drive for the 0B2 in an A4 sedan/avant or an A5 is 38:11.
B5 rear diffs with appropriately geared transmission are compatible. B5 rear differential are NOT compatible with any B6/7. The B5 Quattro rear differential casing incorporates a long extential / tail, which the B6/7 don't. This gives the B5 a lot shorter propshaft. AUDI A4 Avant 1.9L TDI quattro 5MT (110 HP) AUDI A4 Avant 2.5L TDI 5AT (150 HP) AUDI A4 Avant 2.5L TDI 6MT (150 HP) AUDI A4 Avant 2.5L TDI quattro 5AT (150 HP) AUDI A4 Avant 2.5L TDI quattro 6MT