the FWD E56 gearbox comes with a viscous LSD, can take the helical mr2 turbo diff, and has a slightly shorter final drive and 1st to 3rd gears than the s54 box that came with the beams, good luck finding one though, but the great thing about this box is its easy to get different final drive ratio's for it. I have an E56 with a 4.933 final drive
