G,day all My question is how much diff grease should i be using when iam doing maintanance on them. should it be just a light smear over the bevel gears to coat them or should i pack the grease in there so they dont run dry and seize, its a question that has been on my mind for a while. Please has someone got any answers or ideas.

Firstly, what kind of car is it? As you may be better off filing them with silicone oil rather than grease. Anyway, if you stick to the grease route, then yes, put LIBERAL amounts in, you can't have too much (but don't fill it obviously!! lol).

Hi foxy42 The diffs in question belong to a 1/8 kyosho giga crusher monster truck. The diffs were factory built and i have had it know for 18 months or so.The blow apart diagram for the diff shows that it has silicone o,rings sealing where the diff cups go in so would this make it possible to use oil in them. How much oil would you use then. Thanks for your reply.

Yes, it 'sounds' like they are adequately sealed to use silicone oil, but I have no experience with that particular truck. I'm confident it will be ok, and the worst that can happen is that they will leak, and then you'll know. When using silicone oil, use a nice thick weight for a monster truck, like 5-10k depending how much you want to restrict the diff (higher equals more restricted), and fill them 50-60%

Ideally you only need smear, as you said before. The grease only works properly if it is like a coating for the gear surface, if you really pack it in there all that will occur is a buildup where the mass of grease gets pushed to, and if the grease was not applied to the gears properly it will leave bare metal, which will cause wear.

So it's less about how much you use, but more about how you apply it.

Chris.

That's why you need quite a lot, so some is always getting reapplied to the gears, so that no matter where it goes, there is not enough room in the 'empty' spaces for ALL the grease to sit there leaving bare metal.

Anyway, I think it's best to try the silicone route.

Thanks very much for your replies, I,m hoping to do the diffs this weekend coming so i will keep your ways in mind and i will let you know how things go. Ken

Does anyone just use Motor Oils in the diffs? I think motorcycle oil should be fine, since in a motorcycle, the oil lubes the engine and all the gears in the transmission and the clutch.

So, it should do a fine job with the shearing forces on the gears in a diff.

hey aussieken! i have too a kyosho monster truck but not the giga ! the mad force! our trucks use a lof of same parts and one of the are the diffs! the diffs that use kyosho trucks are the same with the inferno so you can use silicone oil! in my mad force i use 7.000wt in front and 20.000wt kyosho oils in the rear! to find the best oils for your diffs try a lot and then you will find what u suit! and a tip for kyosho diffs go with 4 bevel gears! also join the : www.kyoshomonster.com i have join this site is awesome for who has kyosho truck we will help you a lot!