I saw Coopz post on his Matrix leaking in the box, mine that arrived a week ago has the same problem, the diffs feel a little rough/notchy as well. Now I have run 3 tanks through this car but the car has yet to move. Looking at the centre diff housing, pulling the entire thing apart and reoiling it has me a little worried (my closeup vision is not 100% and its been 11 years since I built a nitro buggy). Are there any good shortcuts for topping up the diffs? And why didn't Cen include some documentation with the car on the engine break in, the most important part and theres zero info in the box (ppl without the net` might be in trouble).