Shimming 3s diffs

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Wags1

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Arrma RC's
  1. BigRock 4x4
Question of how and why the 3s blx diffs may need shimming?How to test if diff needs shimming? I assume you hold diff assy in hand and spin ring gear and if it binds in places, diff needs shimming. Is there a shim kit to buy of a different assortment of shims? Any videos that may be helpful? Finally, where to place the shim, behind or in frt of bearing? Thanks guy's!
 
Question of how and why the 3s blx diffs may need shimming?How to test if diff needs shimming? I assume you hold diff assy in hand and spin ring gear and if it binds in places, diff needs shimming. Is there a shim kit to buy of a different assortment of shims? Any videos that may be helpful? Finally, where to place the shim, behind or in frt of bearing? Thanks guy's!
I've never shimmed a 3s diff.
 
In my opinion, no.
Well, can u tell me if I'm right if when testing a diff by holding the diff assy in ur hands by spinning the ring gear, inside the the yoke halfs, if it binds at all in places then u need shimming?
 
Well, can u tell me if I'm right if when testing a diff by holding the diff assy in ur hands by spinning the ring gear, inside the the yoke halfs, if it binds at all in places then u need shimming?

Because of the nature of plastic and how it flexes and bends, this will happen with the 3s diffs. I find it to be normal. Try not to crank the yoke have screws down too tightly. If you mess with it you can get them pretty free. If you really want to shim the outside, take the one shim it comes with, measure it and get some more. Then you can play around with it. The stock shim is on the non gear side.
 
Because of the nature of plastic and how it flexes and bends, this will happen with the 3s diffs. I find it to be normal. Try not to crank the yoke have screws down too tightly. If you mess with it you can get them pretty free. If you really want to shim the outside, take the one shim it comes with, measure it and get some more. Then you can play around with it. The stock shim is on the non gear side.
Ur right. They did have the screws too tight from the factory. It did seem smoother when I loosened them a bit.
 
Ur right. They did have the screws too tight from the factory. It did seem smoother when I loosened them a bit.
Unless you have your slipper super tight, it’s almost impossible to break the diffs/input gears. I’ve done it but I run a tight slipper and launch my truck. It doesn’t always land on all four!
 
When I tested mine (by holding the yoke and spinning the pinion gear) it did bind at a specific place, when I opened the yoke I saw a shim on the ring side, so I moved it do the other side and it solved the binding. When the gears will wear out I’ll move the shim back to the ring side.
 
Unless you have your slipper super tight, it’s almost impossible to break the diffs/input gears. I’ve done it but I run a tight slipper and launch my truck. It doesn’t always land on all four!
Thanks for ur input!
 
Unless you have your slipper super tight, it’s almost impossible to break the diffs/input gears. I’ve done it but I run a tight slipper and launch my truck. It doesn’t always land on all four!
I run my slipper at 1/2 to 3/4 from tight.
 
Don’t know how people get away without shimming these. I’ve got a big rock v3. From stock I stripped 3 rear and 3 front diff and inputs until I figured out shimming correctly on these.
definitely need shimming! I check mine every 5-6 battery packs (due to previous bad experience) as soon as the plastic wears it gets loose and needs a shim, if not 5-6 packs later it’s stripped !
 
how do you set your slipper? also what tires do you use?.

I never stripped a diff, i replaced one due to the theeth getting really thin, but it did not strip (After 2+ years). I have a Typhon and a Senton, so tires are light in my case, which i feel is what mostly count
 
how do you set your slipper? also what tires do you use?.

I never stripped a diff, i replaced one due to the theeth getting really thin, but it did not strip (After 2+ years). I have a Typhon and a Senton, so tires are light in my case, which i feel is what mostly count
Slipper is set to YouTube videos. Hold 2mm hex in bolt, roll truck forward until rear wheels lock and stop. Truck is complete factory set up. It’s been a nightmare, only had it now 7weeks or so.
loads of people say these diffs are ‘indestructible’ Not in my experience. Only running on flat surface too, as I’m scared to keep stripping after 6 batteries, was getting expensive
 
Hold 2mm hex in bolt, roll truck forward until rear wheels lock and stop.
then you're running locked slipper, which explains the diff issues.
That youtube video is terrible advice IMO.

Try 1.5 turns from locked. I use around 1.75 turns from locked
 
then you're running locked slipper, which explains the diff issues.
That youtube video is terrible advice IMO.

Try 1.5 turns from locked. I use around 1.75 turns from locked
Any looser and the slipper just screams and power doesn’t get down at all.
so then I tried Arrma recommended setting as you suggested and I think fully tightening and loosening 1.5 turns has stripped the 2.5mm thread on the slipper hub assembly. Had to purchase a new one as it then wouldn’t tighten at all. Must have over tightened or they are just weak.
 
Yes, it should be tightened lightly by hand, no need to force it.
Or do the "until tires stop" trick, but note that it fully locks the slipper, so go down from there/
 
Yes, it should be tightened lightly by hand, no need to force it.
Or do the "until tires stop" trick, but note that it fully locks the slipper, so go down from there/
Ok thanks , I’ll have a play tonight.
 
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