What size shim do i put behind the input gear on my kraton diffs?

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Is this the kind of thing you were after?
 

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Which model Kraton are you talking about? I'm presuming it is the 4S? the AR709035's are discontinued and for older models like the Fazon. The others are used with the 3S and 4S lines and I'm sorry I don't have experience with the 4S however the following picture taken from the Interactive Exploded view of that vehicle on the Arrma website should give you an idea on where to put the AR709049 ones
 

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Let me clarify a bit. There are three pinion gears on these vehicles. (1) on the motor & (1) each in the front and rear diffs (the ones in the front and rear diffs are also referred to as input gears). Sorry, my terminology from 1 to 1's bleeds over when referring to some parts. I also tend to call the crown gear a ring gear. Anyway, the input gears in the diffs are what I was referring to in my previous post.
 
Which model Kraton are you talking about? I'm presuming it is the 4S? the AR709035's are discontinued and for older models like the Fazon. The others are used with the 3S and 4S lines and I'm sorry I don't have experience with the 4S however the following picture taken from the Interactive Exploded view of that vehicle on the Arrma website should give you an idea on where to put the AR709049 ones
No it's a V2 6s and I wanna shimm the input gear like this... I want too push the input gear tighter too the ring gear.
No it's a V2 6s and I wanna shimm the input gear like this... I want too push the input gear tighter too the ring gear.
So I need a shimm that's 19mm od with 8mm id
 

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OK gotcha. I don't shim that one on my V3. I use the Mugen Sieki shims internally and without actually pulling my diff apart I would think these would work but don't know
 
OK gotcha. I don't shim that one on my V3. I use the Mugen Sieki shims internally and without actually pulling my diff apart I would think these would work but don't know
I've got a V2 and it's got a bit of lash. I'm running PROLINE TRENCHER X so I don't want no lash or I'll be blowing diffs
 

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I don't shim the input gear on any of my 6S Arrma's. I don't believe anyone else does. The backlash at the diffs you are referring to can be addressed with the shims shown above in posts. You shim the planetaries within the diff cup. You shim the bearing at the dog bone cup ( Ring gear side)to adress the input/ring gear slop. I believe that is what you are looking to accomplish. You want to shim the ring gear toward the input gear. Not shim the input gear inward to the ring gear. Assemble all dry and fit shims first to check for adequate play. Too tight and you will ruin the diff. Pretty fast.
Hope this helps if you are referring to a 6S rig.
 
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You can't really shim that gear. You can slide it out a little further as the shaft has that flat section on it, getting that exact will be hard but if you do just locktite it to billy-o
What if I put the shim behind the bearing in the diff housing. I just wanna push the pinion into the ring gear so its tighter
 
I would need to be on my bench to verify and not on the train, but it might work but it might need to be behind the internal bearing, the one inside the diff case opposed to the larger one on the cup side of the diff. It still isn't something I'd be keen to do. What problems is the current setup causing you?
 
What if I put the shim behind the bearing in the diff housing. I just wanna push the pinion into the ring gear so its tighter
No it is not done with these diffs. Shimming these 6s diffs has been discussed at length here and elswhere. You don't shim the input/pinion gear. You do shim the ring gear towards that input/pinion gear.
You seem very insistent on doing the opposite. You seem confused about shimming.
 
No it is not done with these diffs. Shimming these 6s diffs has been discussed at length here and elswhere. You don't shim the input/pinion gear. You do shim the ring gear towards that input/pinion gear.
You seem very insistent on doing the opposite. You seem confused about shimming.
Well I've got as many shims as I can fit in there and there is still lash in the the ring and pinion. I can move my pinion atleast 3/16 either way. And I'm running proline trencher X. And if it's not good and tight I'll be changing gests all the time. If I can get it snug but not tight I won't break gears. I've been working on cars for thirty years and got a pretty good idea what should be acceptable lash in the ring and pinion. It's a used rig and mabey its worn more than normal idk. But its loose and I cant afford to be buying all kinds of stuff. Shims seem like the easiest way to take up some of yhos slop.
Well I've got as many shims as I can fit in there and there is still lash in the the ring and pinion. I can move my pinion atleast 3/16 either way. And I'm running proline trencher X. And if it's not good and tight I'll be changing gests all the time. If I can get it snug but not tight I won't break gears. I've been working on cars for thirty years and got a pretty good idea what should be acceptable lash in the ring and pinion. It's a used rig and mabey its worn more than normal idk. But its loose and I cant afford to be buying all kinds of stuff. Shims seem like the easiest way to take up some of yhos slop.
Ringt now I have three shims on the gear side that are 13x.15and it was hard too push it in. I hot a new ring and pinion on my old cup
 
I would need to be on my bench to verify and not on the train, but it might work but it might need to be behind the internal bearing, the one inside the diff case opposed to the larger one on the cup side of the diff. It still isn't something I'd be keen to do. What problems is the current setup causing you?
Ok I understand that most people don't shi. The input gear too the crown gear. But I also hear people say that if they run bigger tires it wrecked the crown and pinion gear. When I hold both output cups and turn the input left to right what would you say would be an acceptable lash back and forth. I just feel that theres too much play and it would jump a tooth under pwr
Sounds like you are trying to save something that's done. Maybe you should check this out.
https://jennysrc.com/collections/ar...fferential-diff-50t-spur-gear-typhon-ar106021
Or this.
https://jennysrc.com/collections/ar...rrma-outcast-6s-2018-diff?variant=33108991878
Parts wear and you can only shim up to a point. Gears wear out. It doesn't matter what Tires you are going to use.
Ok I put brand new gpm crown and pinion. And I've got three .15 shims in there now. It just seems like theres too much play
 
Are you sure the lash is at the input and ring gears? Your satellite gears inside the diff cup housing can get real sloppy as well. Are these shimmed? Buy an input gear and ring gear. Take it from there. Cheaper to buy an assembly from a dismantler. How much shimming did you ad to the left side (ring gear side) cup bearing?? You should be able to shim this location and reduce the lash at the input/ring gear contact. If you cant, you need new parts.
Some amount of backlash is required! Think about pinion mesh at the motor and center Diff. A papers thickness worth of lash is what you want. Worn parts increase unfavorable run-out.
A sloppy topic. Lol
 
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Perhaps most people don't shim at all. At least initially. But those that do, like myself, just don't shim this particular input gear/ring gear setup at the "input gear". You should shim the ring gear towards the right to the input gear to correct lash.
Sounds like you have a group of worn parts to evaluate
3+ or more MM of shimming and you will risk moving the whole diff too far to the right and the left output cup will lose the left dogbone at extreme articulation. You end up moving the diff. too far off center. Trial and error dictates how much shimming you can get away with. But at some point there are many worn parts to consider replacing.
 
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