[Gustav]

It's not that kind of diff Nbcazn,it's a ball diff and has a screw running through it which you tighten or loosen to adjust the diff.It's normally done without any disassembly so you can make very quick adjustments for racing.

It's not difficult,basically with the 4200 you're going to need the diff and the slipper reasonably tight,you know when one is slipping because you can hear it(diffs 'bark' when they slip) and the outdrives will be hot.

You always want the slipper to slip before the diff beacuse you never want the diff to be slipping,but in this case you want them both fairly tight,otherwise the slipper will overheat.When we say the diff slipping we mean the whole unit slipping.ie both outdrives slipping on the balls.

The other thing is you need to be aware of is if you have the diff too tight it will overheat aswell because there's so much friction when it diffs out,so keep an eye on the temp of the outdrives 'till you get it adjusted,it should still feel smooth when you tighten it.

If you take it apart and have a look and read the manual it'll all become clear.You will have to get used to rebuilding the diff once in a while if you're going to keep it for long.