I am going to replace the grease in my Jammin X1 RTR with Diff oil with 5k, 7k, and 1k (front to back). According to my manual it says to fill the front and rear diffs 100% and the center diff 80%. So I have filled my front and rear diffs 100% (basically I filled the housing to the top and when I placed the ring gear on excess oozed out of the screw holes, I wiped off and screw the top on.) I haven't started on the center yet.

Anyway, now I have seen some forums that advise not to fill 100%. Are my front and rear diffs going to be OK or should I take them back apart and let some of the fluid out?

Thanks.

Does anyone have any input on this? I hear mixed opionis. Some folks fill 100% and report no problems. Others have said that it will case the differential to leak. And others report to only fill right above cross pins.

Thanks.

i think it will be OK but i would say it's better to only fill them 80%, because they will work better.

Filling them 100% is fine. I usually do that and then let the excess bleed out. I find that on the conditions i race in it is actually better that way.

Filling your diffs all the way will make it push the oil out of them. front and back shouldn't be a problem, up until the excess oil in the diff housing mixes with dirt and starts wearing out your gears. (if you seal up the housing and clean up the diff housing when it gets dirty in there it would be alright) i guess it just a maintance thing. i fill mine up to above the cross pins seal up everything and then forget about it. (i'm lazy).

definatley don't over fill the centre diff. oil on brakes, not good.

Treat your diffs like you treat your shocks----You don't want any air in them---if you have air in them the diff will not be consistant----fill to 80-90%, slightly rotate outdrive back and forth to let air out of gears---let the diff sit until all the airbubbles have come to the surface,assemblewith seal(oil will be comming out of the screw holes as you tighten)clean the diffand you ready.