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Old 01-22-2014, 07:03 AM
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MantisWorx
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Originally Posted by JLock
I don't own a Team C car but have built many diffs for my Kyosho GTs and have never blown a diff since I have been running GT. Maybe it is not the heat coming off the engine more so the build and/or heat generated in the diff itself. Or, it could be an issue with the quality of some of the gears (material) that is causing the failure (a theory). When you guys build your diffs, are you overfilling or underfilling the diff before putting it together? When you build your diffs, are you sealing them properly (using more than just the diff gasket)? If you don't seal them properly, a leaking diff eventually turns into a diff running on metal to metal which will crash and burn on you. Are you guys lubing the ring/pinion gear in the diff case? Most people forget that metal on metal generate a bunch of heat (friction) and many racers don't think about coating either gear with a layer of grease to ease the friction issue. One more thing, are you using the right diff oil for your diff? I state this because of the types of engines now being used generate a lot of power through your drivetrain. Using too lite of a diff oil with a very powerful engine (especially with a ton of low-end torque) could be something else to look at as far as causing diff failure.

Again, I am not trying to step on any toes but throwing some things out that might help you guys to alleviate some diff issues.

No worries and thanx for the advice!

As most of you know i have been working with this car for over a year now. It is most definitely the heat coming off of the engine heat soaking the gear case. I have been from 1k to 100k in rear dif fluids and it still happened. the factory changed materials a few months ago and it got better but still there. It is not a dif failure it is the external dif case that fails and anyone that has had it happen will tell you that the inside bearing gets destroyed once the case gets hot and distorts. This past weekend in HK they had a 3hour endurance race and 99% of the cars were team C , every car that had the helical stock r/p failed within and hour and every car that had the optional straight cut gearset finished the race! So two things come from this IMO one is that helical gears create heat this is a known fact , it is also a known fact that helical gears must be precisely shimmed or else the create excessive drag. this past weekend in homestead I had a shield and had no failures Tony had no shield and his rear case failed. Another thing to think about is that helical gears will "pull" fwd and back on accell and decell, straight cut gears do not, the more i talk about the more sense it is starting to make

Jlock, everything you state though is very much true!
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