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Problem w/ center diff wearing out???

Problem w/ center diff wearing out???

Old 03-11-2010, 05:17 PM
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Default Problem w/ center diff wearing out???

Now given, I am running 6s through the MM2200 in my VE.. the two shafts are wobbling alot and im wearing out diffs WAYY too quickly! Am i wearing out the case? bearings? do i need to shim? please help!

I need to figure out what i need to replace insted of buying a whole new center diff...

Last edited by *BBB*; 03-11-2010 at 05:43 PM.
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Old 03-11-2010, 05:20 PM
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MMM2200 x 6S=Need I say more.
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Old 03-11-2010, 06:13 PM
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i know it! lol but i need to know what i need to be replacing or upgrading
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Old 03-11-2010, 06:28 PM
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With that much power, the diff oil is becoming plasma and some kind of anti-gravity is tearing things apart.
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Old 03-11-2010, 06:41 PM
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You should be able to tell if your diff case is worn out by looking at it. It may be as I've had that happen in other cars when the bearings wear out and you keep running it. The diff case will look a bit melted around the bearing hole. If it's fine, then your bearings are dead. You might have to shim it a bit tighter due to all the power.
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Old 03-11-2010, 06:50 PM
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Ok ill swap the bearings bc it sounds like the case shouldnt be bad.. But i spun the bearings and they were nice and free but maybe the inner ring has worn down?

Also what does adding the shims do?

thanks
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Old 03-11-2010, 06:57 PM
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MMM 2200 on 4s is stupid fast, on 5s is super stupid fast, 6s is just stupid. Literally stupid. No need for that. I'm not surprised you are having drivetrain issues.

Anyway, there are a number of things that could go wrong in a center diff. If the bearings are free and spin smoothly, they most likely aren't the problem. You need to open the diff up and find the failure. If you are using grease in the diff, that could be a problem too. It needs to be filled with silicone differential fluid. Something like 7000 weight. If I remember correctly, the lower end kyosho diffs only used 2 small bevel gears and 2 large crown gears (4 gears total). If that is the case, you will want to upgrade to a 6 gear diff(4 small bevels and 2 large crowns). You can do this by simple adding 2 small bevels as well as a second cross pin. They may have already updated them to 6 gear diffs, but I know in the past their RTR stuff was only 4 gear.
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Old 03-11-2010, 07:25 PM
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Jammin, u know what dude.. u must have a miserable life. Ive seena few negative post from you before... where do you get off?

The 6s is actually Perfect for my track and application as i need a little over 60mph to top out on the straightaway
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Old 03-11-2010, 08:10 PM
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Contact hpi and ask them if you can run a aluminum diff case made for the savage aftermarket, or get aluminum risers that hold the diff in place to eliminate flex from all that power your putting down! 60mph, at those rpms I'd run ceramic bearings for sure and a steel spur. Check out acer bearings.
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Old 03-11-2010, 08:30 PM
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Upgrade to the Kyosho 777 diff.

2200 with 6 cell is pretty crazy though...
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Old 03-11-2010, 08:44 PM
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There are 2 bearings, and inner and an outer. The outer might spin fine, but the inner might be dead. Best to open up the diff. If there's play in the drive cup, one or both of the bearings are usually gone. And if you keep running it like that, the rpm and heat from rubbing will melt and warp the diff case at the bearing hole.
Avid is my favorite for bearings. Cheap and excellent quality. And the owner is a great guy to work with.
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