Thanks for the replies, l Will to buy a final drive (Torsen) from a 405 Mi16, assemble with the crownwheel and pinion from 504, it fits? I run mist of the car on ice, hoping Torsen works well on ice?? Quife sell diff to 505, what is the difference to 405 (505) Torsen? My car: 504 Diesel 1971 modell code A20. Has cage mounted in the car, plastic windows, battery in the rear, aluminium hood, the engine is back moved 5 inch for better weight distribution, rear springs from 505 Turbo somewhat shortened, rear crossmember welded instead of silentblock, rear swaybar from 604, Bilstein gasshock from Alfa Romeo, Rear wheels modified the Wide rear track 1425mm is almost the same as 505. Front: springs orginal cut (diesel), 604 lower control arms and 504 caster bars. New holes drilled för the struts, the more camber. Swaybar 505 Turbo, steering rack 2.9 turns 505 turbo, dual shock absorbes, no gas, no power steering, no braking power. /Bobby