I took my rear diff apart in my raze to basically just look it over. When re-assembling it, I absolutely could not get the red rubber ring to stay in place long enough to put the two main diff assemblies back to together (kept popping off as soon as I took my finger off it). Is there a trick to doing this, or is it just an exercise in major frustration?

lol! Fun, isn't it? Practise makes perfect.

Can anyone give their technique? To further complicate it, there is no way to tell after you've combined the two parts whether the ring popped off inside the diff at the last second...AHHHHHHHHHHHHHHH

My only tip is to stick it in there with some grease (which will also help the seal). I must say I don't have this problem with Xray diffs, but it was a NIGHTMARE on my old HPI R40. There's not much you can do but persevere. Take a cigarette break between attempts.

Thanks foxy. I feel a bit better knowing that its probably not me...just an awkward process. It is a bit irritating though since it seems they could design the parts to retain the ring better while assembling.