Diff's
 

I'm about to rebuild the diff's on my fs2 which is something I'm not very good at. Any tips welcome

Put some Durango 410 gear diff in it ;) I have and i'm very satisfied.

Or just use the existing ball diffs with some decent balls and grease and they will be spot on..

All I've ever done is built mine to the manual with ceramic balls and they last ages, feel ultra smooth etc.. all these people that sand discs etc must be mad..

And as for swapping for a gear diff.... why try to fix what isn't broke??????

Agree with x313 here, get some new plates and decent ceramic balls, I always clean the plates with a bit of solvent to remove the grease they have on to store them in the packet. Make sure everything is clean and use some high quality lubes, I use the nuclear stuff which i find excellent.
Thin coating on the plates then a little bit more on your finger tips to pick the balls up with and put a light coating on them at the same time - maybe replace the main diff gear if it's particularly grubby, pack the thrust race with black grease, unlike the main plates you can flip these and re-use if they have a deep groove - if your diffs feel rough it'll often be down to grit in the thrust race. You need to remember all these parts are consumables and will need replacing every so often to keep the diffs silky smooth and working at their best.
I saw in another thread somebody wondering why they are stripping teeth off a gear diff, and it's down to the insane power we are trying to put through the transmission, a gear diff allows zero slip so is more prone to fail if the slipper setting isn't spot on, keep it balls!! :thumbsup: