Winner's Circle

iTrader: (2)

This is a great questions. I would like to hear what others have learned from changing diff oils.

I have tried from 30,000 to 100,000 in the front and from 6,000 to 50,000 in the rear on my Kyosho GT2. Right now I have 60,000 in front and 6,000 in the rear. I have 200,000 and 300,000 on order now to test in the front diff in the near future.

Here is what I THINK I have learned from my experiments;
- Heavier oil in the front diff makes the car stable but it also makes it push
- Heavier oil in the rear makes the car loose under all conditions (on or off throttle)
- Lighter oil in the rear makes the car push under power but the turn in off power is better
- in general lighter diff oils make braking more difficult and with my set-up make me have to brake more in a straight line before the turn to avoid making the car spin out

The straight cut diff gears (if106 - 43T & IF21 - 13T) are much more reliable than the kit gears and I strongly recommend using them.

The Kyosho diff housing (if103) will allow the 4 screws that hold the ring gear to loosen after you disassemble the diff a few times to change oil and it will need to be replaced. I suggest that you have a few extras on-hand.

When you try a different viscosity, I suggest that you make a fairly big change in order to be able to tell what a significantly heavier or lighter oil will do to the way your car handles. I have found small changes to be hard to notice.

If you change bodies, tires brands, tire shore, set-up, the track you are running on, or if the track temperature goes up, you may want to experiment with diff oils again. I just recently changed bodies from the Corvette to the Ipanema Warrior and this change resulted in my car having more steering now so I am trying different oils again. I plan to go to a heavier front oil.

Lee