stronger diffs

[DO-U-MAXX]

What is the best way to strengthen up the stock diffs without going to 1/8 scale buggy. I have seen aluminium diff cups to replace the stockers and I know about alum. covers but which offers the best bang for the buck.
I do not have any problems now but just helping out the stock DT as much as possible before upgrading, slowly, to higher performance parts.

[Mr. Tune]

In the savages, there's only 2 spider gears in the diffs. I've added 2 more to mine to strengthen it up. My diffs are holding up fine to the bigger motor. Not sure how the t-maxxes are setup, but I'm sure it's the same concept.

I know of aluminum diff cups, but they are a tad expensive for the savages. I think they are around $50-$60 each. I'd rather just replace it with a stock cup if it breaks.

[Tex]

I run stock diffs... when they break I buy new assembled (pulled from new truck) on the Bay... they last anywhere from 2-4 gallons for me and run about $15-$20 each on ebay

[DO-U-MAXX]

cool, but does any of those above mentioned upgrades really save the diffs or are they just an unnecessary upgrade.

[Mr. Tune]

In my case, it's a easy upgrade with great results. Much easier to break 2 spider gears then 4.

I've had zero problems.

[Tex]

he runs a maxx and you run a Savage :p your upgrades won't help him as you cant add spider gears to a maxx diff

DO-U-MAXX, I hear people saying they break maximizer and kippster diffs just like the stock ones so I would stay stock or go, UE supermaxx diffs (about $300) :o

[DO-U-MAXX]

I'll just stock up off ebay...........thanks guys

[Jack]

If you shim the diffs they should last a long time. I ran about 10 gallons and three engines (stock, XTM24.7, Mach 26) and I finally broke the front diff, the rear was still good. I feel the stock maxx diffs are good, they just need to be shimmed.

[DO-U-MAXX]

what do you mean by shimming. I know what the word implies but how do you do it?

[DO-U-MAXX]

ok, I think I need to shim my diff now. It sounds like they are skipping when I accelerate but not when I brake or turn them by hand. If I hold the front tires and turn the back tires as if its going forward, then I can get the rear to skip when I apply a load to it. The front seem fine when I do this so I think I will take it apart tonight and check it out. Does anyone know where I can drive and pick up some shims tonight?

[Jack]

I forgot what kind of shims I got for my diffs, so you may have to do some hunting to see what fits. I don't know of any hobby shops open late except for Hobby Town in Naperville.

[DO-U-MAXX]

I got the bug and took out the diffs now. I located some shims to use and I decided to rebuild both anyways. They are starting to get a little wear on the gears so i think I did this before too much more happened. I did notice that one of the gears in the idler gears already had a shim so I think the guy who I got it from shimmed it cause I know I did not.

[Tex]

go to traxxas and search the forum there for Diff shimming or something. it'll show you exactly where to put the shims and what kind to buy

[DO-U-MAXX]

yeah, thats what I did yesterday, I rebuilt both of them. I noticed that they are starting to wear on the high side of the pinion and the middle of the gear. Odd, I thought it would be the front of the pinion and the end of the gear. Its hard to determine what is causing them to wear that way. Any ideas?

[SixVi6-Camaro]

Its common. the QC on the Maxx diff gears is marginal. When I ran stock diffs I found that I'd have one diff with perfect mesh and wear patterns and the next 4 would be way off. Some of this uneven wear comes from the diff housing flexing under power especially with a .21. eventually the pinion will wear until it begins to skip teeth and it rounds off the teeth. you will hear this especially under breaking as a clicking noise. be carefull going to RRP gears with a .21 unless you are putting AL diff housings and AL diff cups into the truck. RRP gearsets are hardened to the point where if skips a tooth it cracks teeth clean off the pinion rather than just slipping over each other. :eek:

[DO-U-MAXX]

I thought about using al diff everything, but the $$$$$$$$$$ is out of the question right now. i only hear a clicking sound when I accelerate not brake. And the gears looked decent but not perfect. I will run it toight and see if I still hear the click. I may take apart the tranny and get a look inside, but everything rotates smoothly with no sound when i turn it by hand.

hmmmmmmmmm????????????????????

[SixVi6-Camaro]

Exactly! All AL diff setups are $$$$$. that is why I just saved that money and bought the UE 1/8's instead of screwing around with the stock diffs. UE 1/8's cost the same amount of money as buying AL housings, diff cups, and RRP gears and I've had the 1/8 diffs since they were first released and no ring/peione wearing or breakage just a once a year spider gear rebuilding costing $20 total.

hmmm.... clicking on aceleration. icould be the tranny mabey diffs still depending on how hard you are on the breaks. I had a dual disk setup on mine which gave incredible rear wheels up stoping power but it was also hell on the poor diffs. if you don't get it figured out bring it on the 21st and run it because I know several of us will know if its the diffs or tranny just by the sound.

[DO-U-MAXX]

It has no sound at all when I brake. I have a custom brake pad on a robinson disk. I have the robinson shoes but not installed, I made these shoes when I wore out my robinsons. I do not brake that hard to get the rear wheel lifting but I can if I mash them, which I try not to do. What in the tranny would make noise when accelerating but not be there when I spin it freehanded? I want it 100% before this weekend but if I don't figure it out I will gladly let you check it out. I have to get the tune in better hopefully before this weekend.

[SixVi6-Camaro]

hmm.... It depends on how you are spinning the tranny... are you spining the tranny by the spur gear or by rolling it around on its wheels. Because if its a stock tranny the internal clutches for fwd and rev on the maxx if you try to roll it on its wheels the tranny clutches are disenguaged and noting in the tranny will spin. spin the spur gear in both directions (I forget if the one way bearing will effect the gears spinning or not) and feel for anything abnormal. even the slightest hang up you feel on the spur can translate to some good noise under power. it could be a chiped tooth in the tranny even a piece of something in the egar mesh of a tranny gear.

Heck actually it coudl also even be a small stick or something silly jambed into a rim or in the driveline someplace that just isn't hanging up under breaking. dunno for sure. it would not hurt to crack open the tranny and check the gears to be safe.

[DO-U-MAXX]

yeah I may just do that tonight if it rains and I can't get out and test it some more. But I have the FOC so the spur bites one way and not the other, and its free when it turns the wheels. so still, hmmmmmmmm??

[DO-U-MAXX]

No need to take apart the trans, I tested it tonight and after the diff rebuild...........AOK. NO clicking or anything. Nice wheelies and decent takeoffs and no sounds whatsoever.
I think if I would have let it go on, I would have caused some more serious damage which would have made the LHS bill higher than the $20 I dropped tonight on the repairs.

[DO-U-MAXX]

No need to take apart the trans, I tested it tonight and after the diff rebuild...........AOK. NO clicking or anything. Nice wheelies and decent takeoffs and no sounds whatsoever.
I think if I would have let it go on, I would have caused some more serious damage which would have made the LHS bill higher than the $20 I dropped tonight on the repairs on the front end..............see other post for story if interested.