Originally Posted by
MidwestRacer
I have been racing Yokomo cars and many other brands also. Diffs leak due to improper assembly. Over-torquing screws, re-using gaskets, over filling etc. I have a 3 year old diff in my Yokomo VTA which I haven't had apart in 2 season and still doesn't leak a drop. The only diffs I have had leak were a Sakura, which turned out to have a defective o-ring and my 1/8 offroad after the dirt gets into seals and wears them out. Its all in the details and meticulous assembly process.
BD9 diff is still leaking from the diff cup, it is not about how you assembly. The oring is leaking...... We have 3 BD9 and all leak. Check your diff inside, may it is already dried. We have to use other brand's oring to fix this leaking.