Is there a better diff design out there?

[8000ft]

As we all know the rear diff can not be sealed to hold diff grease for any length of time and I really don't like the locked rear end for playing in the snow. Locked diffs make the rear end get real squirrely.

The diff itself also is tasked with handling a huge amount of power and torque and the little tiny screws and threaded holes are a real weak link.

Has anyone come up with a bigger and better design?

[gbean]

your only option for an open diff is a GCM diff cup and HPI spider gears.

[WHITE-TRASH]

Originally Posted by gbean

your only option for an open diff is a GCM diff cup and HPI spider gears.

I think he's looking for something between open and locked. I don't think there is any off the shelf way to seal an existing diff with straight axles installed.

I've thought about thin rubber between the diff cup/ring gear to force the side gears in tight but it would likely be shot lived.

[8000ft]

Yes I have tried to use some thick TrakPower Gear Grease but after a while it seeps out past the axle inputs. I'm looking for something that is like a Detroit Locker.

[opie]

Would silly putty work? I know some people run it in the front diffs.

[DenisLM]

I'm about to try open the rear diff with the hpi spider gears and 1mil oil. Also I'll try to put o-rings in the axle ends to hold the oil inside the diff, which probably going to work because the oil is insane thick. I used in the front diff and is like a step under the silly putty.

[mojave450rider]

I got a decent success out of using Exo spider gears and using the red o-rings inside and out like they are suppose to then drilled and tapped a 4mm hole in the plastic diff case assembled the axles into the case in the axle then used diff oil poured in the hole I drilled in the diff case then used silicon on the 4mm set screw to hold the fluid in.

[8000ft]

I would think that the silly putty would be a complete lock up. I have use the red o-rings also with the grease which is much thicker than 1 mil oil but it still seeped out into the axle tubes.

I guess that grease is still my only option, bummer.

[Mudman]

Man wouldn't it be great if someone made a tunable scale limited slip diff?

Hope you find a solution, this topic really intrigues me.

[Bry73]

I use something close to Silly Putty in my front diff on my Wraith. This stuff is called Crazy Aaron's Thinking Putty, I picked it up at my local hobby shop/toy store/My Work location. It is really thick and has yet to leak a drop past the axles. It acts as a locked diff going straight ahead and even when I get to an obstacle it will then work as a limited slip. The side that has grip still pulls even though the wheel not on the ground may be spinning a little faster. Though after a while it does warm up it does spin a little free'er, but once cools back down still just like it came out of the can.

Oh this stuff is also Made in the USA and there are several different types. The one I am using is called Super Scarab, there is also magnetic and mood color types.

[maxPOWAAA]

Use Macks silicone ear plugs found at any drug store over silly putty. It will not dry up or get hard like silly putty does

[8000ft]

I think that I will order some of this and give it a try. It's not a total lockup is it?

Originally Posted by Bry73

I use something close to Silly Putty in my front diff on my Wraith. This stuff is called Crazy Aaron's Thinking Putty, I picked it up at my local hobby shop/toy store/My Work location. It is really thick and has yet to leak a drop past the axles. It acts as a locked diff going straight ahead and even when I get to an obstacle it will then work as a limited slip. The side that has grip still pulls even though the wheel not on the ground may be spinning a little faster. Though after a while it does warm up it does spin a little free'er, but once cools back down still just like it came out of the can.

Oh this stuff is also Made in the USA and there are several different types. The one I am using is called Super Scarab, there is also magnetic and mood color types.

[Bry73]

No it isn't. If you hold 1 wheel you can turn the other wheel. if you hold vehicle up in air and turn 1 front tire all 4 wheels will spin in same direction, if just holding rears locked the fronts will spin in opposite direction.

[Budman]

What axle shafts are made to work with a open (spider gears) diff for the rear ocp ar60 housing,I don't remember seeing any that have the groove for an e-clip or the o- rings for that matter. Maybe I haven't looked hard enough?

[gbean]

The original shafts work.
The bearing in the end of the housing holds it in.

[terrible]

Something like the losi "smart diff" would be nice. They were supposed to be like a detroit and only lock when loaded and allow enough differential action for turning.

[8000ft]

mixed results on the Aaron's Crazy Putty, It seemed like it would be the hot ticket when I tested it in my shop right after i installed it. However at a warm 36 degrees out and running in snow it got super stiff and essentially locked up the rear end completely. I will leave it in for now.

[DeviledEggs]

It would be awesome to see a clutch type LSD but I dont see any winged pigs around here.

[8000ft]

I pulled the putty out, even when I warmed the diff up with a hair dryer there still was no slip and in fact when i held one rear tire still I heard the giff gears slip teeth twice, soooo out it comes and the grease goes back in.

something like a slipper clutch would be great, with an external screw adjustment.

[Bry73]

I hadn't run it so the diff was down in the snow, was working well out on the ice drifting my Wraith, but I will keep an eye open for the slipping of my diff gears.