Shimming Diff Tight or Loose?

[norco kid]

While I was assembling my rear axle I noticed the diff itself had a bit of side to side play within the housing and I decided to add a 0.2mm shim between the ring gear and the bearing to take this out. Now the diff is a bit tight (rotates smoothly but I can feel a bit of notchiness). There is 0 play between the pinion and ring gear. I have read up on shimming diffs (mostly 1/8 buggy stuff) and some people say to shim them tight and let them wear in while others say to leave a bit of backlash. I am thinking of removing 1 of the 2 shims behind the pinion gear to give it a bit more slack. I know the XL has had quite a few issues with stripping diffs and I want to make sure I get this right to do all I can to avoid the problem.

[Tzicul]

Consider that all that gears can get worm and will dilate. So I don't think 0 play is an option. I like to setup mine as tight as possible without being notchy. And I'm sure the problem with Yeti's diff is not the pinion/gear but the bearings. Did anybody saw a destroyed diff with intact bearings?? I'm on my first set of diffs and I've had absolutely zero problem until now. Except a few teeth, both on front and back, exactly when the bearings gave up. ALWAYS the outer one, never the inner. Happily I was able to stop the car in time to save the diffs.


Sent from my Sony Xperia Z5

[BarHarborBasher]

Originally Posted by Tzicul

Consider that all that gears can get worm and will dilate. So I don't think 0 play is an option. I like to setup mine as tight as possible without being notchy. And I'm sure the problem with Yeti's diff is not the pinion/gear but the bearings. Did anybody saw a destroyed diff with intact bearings?? I'm on my first set of diffs and I've had absolutely zero problem until now. Except a few teeth, both on front and back, exactly when the bearings gave up. ALWAYS the outer one, never the inner. Happily I was able to stop the car in time to save the diffs.


Sent from my Sony Xperia Z5

You have beveled straight cut gears .. correct ?? And you need a boot to protect the outer pinion bearing ..

[Tzicul]

Yes and yes. And I have no idea what to do as a protection. It has to be corrugated and flexible and tough enough to resist down there

[BarHarborBasher]

Heat shrink that is only heated on one end , with shoe glue or a small wire twist to secure it in place on the driveshaft.. OR PRO MOD Steve's style boot !! That looks like the best kind of material !!
Anything will be a HUGE help !!! That thing is like a cement mixer getting dragged across the ground lol

[Tzicul]

I already tried the heat shrink and I didn't liked it, it wasn't corrugated enough. What are you talking about Steve's mod????? Never saw it!!

[BarHarborBasher]

Originally Posted by Tzicul

I already tried the heat shrink and I didn't liked it, it wasn't corrugated enough. What are you talking about Steve's mod????? Never saw it!!

Pinion Bearing Issues

[Tzicul]

Oh, yes, I remember now. However I don't like it very much because it is not seal around the rear axle. Anyway, better than nothing. I suppose I'll do it also until something better comes to my mind. And it will!

[BarHarborBasher]

Deflecting is the main object.. Simplicity is a + as well.. I've been meaning to get onto this but been sidetracked by life lol im interested in your mod !

[Tzicul]

Originally Posted by BarHarborBasher

Deflecting is the main object.. Simplicity is a + as well..

Couldn't agree more. I already have someting on my mind with some cloth air filter cover. Ok, it won't be waterproof, but dust is the main issue here!


Sent from my Sony Xperia Z5

[norco kid]

Did Axial update the diff gears on this thing? The only ones I can find online are silver helical gears where as mine are black straight cut gears..

[Sjonnie82]

GPM also has upgrade set now, which should work ok. Maybe harborbash men can tell as GPM reseller?

[BarHarborBasher]

Originally Posted by Sjonnie82

GPM also has upgrade set now, which should work ok. Maybe harborbash men can tell as GPM reseller?

I have raised this want/demand to GPM .. the #45 steel straight beveled cut gears is all they offer at the moment ... but mid summer expect to see a variety of upgrades

[BarHarborBasher]

Originally Posted by norco kid

Did Axial update the diff gears on this thing? The only ones I can find online are silver helical gears where as mine are black straight cut gears..

YES the only one's they sell are ones that destroy your housings with out a modification...
but if you plan on running it once a month ... it will last 4-5 months without the HD Pinion mod
After the mod they are the Toughest Gears on the market !!! Hands down !!!