quote]ORIGINAL: mozzzy_2000

in regards to diff oil, its usually a personal preference & the surface you most likey run the car on. I would certianly use high quality silicone oil. The theory being that the thicker or the heavier the diff oil, the harder it is for the engine to drive the wheels. So in other words, if you are running on a loose surface you would not want you front diff you spin widly out of control. You would use a stiff oil to reduce wheel spin. Conversely on a high traction track, you would probably use a thinner oil.

The weight of oil will also affect whether you get under steer or over steer. This is so for front & rear wheels and will affect the way you come into & exit corners. The front & cente diffs seem to be the ones that are most sensitive to oil weight & seem to determine the overall performance & handling. The rear wheel obviously don;t lift off like the front does so, you want a thinner oil in the rear so that you maximise drive.

With that in mind there are general weights or diff oil to use in most conditions. If you have the time to tear down your diff & change the oil, you can experiment depending on how you like the car to handle. The stock Redcat/Himoto & Bazook have grease in their diffs. While there is theorectically nothing wrong with diff grease, it is not ideal & you wont be able to change the handling characteristics.

So generally it goes like this.

Front: 3000Wt - 5000Wt

Centre: 7000wt-10000wt

Rear:1000Wt-3000Wt.

In mine at the moment I have 5000/7000/3000 in my himoto and on grass it is awesome to handle. Off-road on loose surfaces though its a challenge & I have yet to experment with the diffs on those surfaces.

The only thing thats a pain in all of this is that you need to take apart the diffs, clean out every trace of grease & then fill it up with the silicone. Its not a bad way to spend the afternoon if you haven;t anything else to do and you'll instantly feel the immedate effects on the handling of the car.

I don;t think my diffs had o-rings either so they can be added for better performance. I have also found that the diffs from the Ofna Hyper 7 & 8 and both the kyosho inferno MP7.5 & MP777, are all the same size & all fit the redcat/himoto/bazooka. I will say though that some diffs have aluminium spur gears & you want avoid those. The stock redcat & Himoto diffs are infact good quality steet gears & so far mine have taken a hammering!

Hope this helps!
Matt
ps. watch that silicone oil! whatever you do, don;t get it on the foor!!! haha
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