How to shim your Arrma diff

[olds97_lss]

Just did 2 center diffs, and wanted to add, naphtha cuts the silicone pretty well. Can be bought from Home Depot, or hardware store.

Nearly 20 years of RC running and I finally figured that out. Sure makes rebuilding a diff so much easier when you use a bit of naptha.

 

[Lazy Bushman]

For the other Aussies on this forum (and other countries where Naptha doesn't exist I guess), our equivalent here is Shellite. I'm not a chemical engineer to know precisely if it is just one of those things that are the same but has a different name or is a completely different chemical compound that is effectively the same thing....so if you can't find Naptha, try looking for Shellite. Diggers is the main brand here (Diggers Shellite) available in Bunnings and Supercheap Auto as well I think


Edit: Yep sold at SuperCheap Auto. I bought a litre yesterday on the way home for about $10 I think

 

[Jerry-rigged]

Naphtha is often sold as Lighter Fluid. But, in the small cans targeted to Zippo users, it is a bit pricy.

 

[Le-Mill]

Do you shim the main pinion in the diff ?
In my case when the 13x16 shim is install the main pinion keep a lot of play

 

[Wmorgan]

Just did 2 center diffs, and wanted to add, naphtha cuts the silicone pretty well. Can be bought from Home Depot, or hardware store.

Just came across this thread and saw your reference to "naptha" cutting the silicone. If you don't mind can you summarize why you want to cut the silicone. I'm guessing the naptha temporarily thins the thicker silicone so it makes filling diffs more efficient??
I'm an old newb at working these diffs and appreciate any sage advice.

 

[chevys10zr2003]

Just came across this thread and saw your reference to "naptha" cutting the silicone. If you don't mind can you summarize why you want to cut the silicone. I'm guessing the naptha temporarily thins the thicker silicone so it makes filling diffs more efficient??
I'm an old newb at working these diffs and appreciate any sage advice.

I think he means that it works for cleaning the old silicone diff oil out of the diff cup and off of all of the gears. That is what use the naptha for anyways.

 

[Wmorgan]

I think he means that it works for cleaning the old silicone diff oil out of the diff cup and off of all of the gears. That is what use the naptha for anyways.

oh yeah...duh. thanks for replying. I'm in the process of rebuilding all of my Arrma diffs (12 total) and looking for any advice/tricks/Do and don'ts/SHORTCUTS!!!

 

[chevys10zr2003]

oh yeah...duh. thanks for replying. I'm in the process of rebuilding all of my Arrma diffs (12 total) and looking for any advice/tricks/Do and don'ts/SHORTCUTS!!!

I used the filter below but in a 1 quart size which they do not show anymore and naptha to clean out all of my diffs and it worked wonderfully. I can also seal it up and leave the naptha in it for later use.

https://smile.amazon.com/gp/product/B06WXXF81Q/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

 

[PaPa Thorn]

A bell jar of your solvent of choice and this.

https://www.amazon.com/Standard-Tea-Infuser-Mesh-Spoon/dp/B000F7DT2O

A few stirs and wipe clean.

 

[Wmorgan]

A bell jar of your solvent of choice and this.

https://www.amazon.com/Standard-Tea-Infuser-Mesh-Spoon/dp/B000F7DT2O

A few stirs and wipe clean.

Good one!!

 

[Lazy Bushman]

hey @Wmorgan check out the following from our very own @Primarrma :

 

[Cr3pitus]

Edit: you can ignore this post if you want I figured it out. It was in fact a poor cut on the spiral 10t input gear. There was a smidge of extra metal on one of the teeth and since spiral cut gears mesh more than one tooth at a time it was impacting 2-3 ticks on the gear. Solved with a quick flick of the Dremel.

I have a diff issue I can't figure out. I just rebuilt the rear diff from all new parts, a full kit - because I didn't have time to clean the old one first. Figured I'd get her up and running and just clean the other out when I can. But now for some reason there is a point on each full rotation of the 43t where it gets janky for what feels like 3-4 teeth. Kind of like the feel when either the 10t or the 43t have a worn out section - except they're both brand new. The internal gears on the diff feel great, but the relationship between the 10t input and the 43t feels like butt. The input gear is perfectly flush against the internal housing bearing and all bearings are rubber sealed and feel great on their own so it's not a bad bearing. What could make it feel like this? Did I get lucky enough to get a lemon 10t or 43t? If so I can't tell by any visual inspection.

 

[Badtouch The basher]

Ok for the guys in the uk on shims for the diffs here is what you need i believe these are the shims for external, and internal on the diffs please see attached

 

[Tempo]

I'm new to arrma so I can't speak for how the diffs in earlier versions were, but in my 2019 notorious and new diff sets ive ordered from jennys, they definately don't need shimming to the extent that some are doing. The only additional shim i left was 1 under 1 of the planetary gears per diff. And then I added another shim on the outside of the bearing to mesh the pinion/crown a bit better. This seems to feel pretty good for me.. ??

 

[Combo]

Ok guys.. ive read this thread 10 times now and i still didnt understand:
1. Which set of shims do i need to shimm my diff in my Mojave?
2. Is my Mojave has 3v or 4v diff?

Thx..

 

[Brandon]

I would think that since the Mojave is new it would have the latest diffs, so v4.

 

[Combo]

I would think that since the Mojave is new it would have the latest diffs, so v4.

Brandon,
Should i buy 3 of these? They fit to Front-mid-rear?

 

[PaPa Thorn]

Brandon,
Should i buy 3 of these? They fit to Front-mid-rear?

I don't recommend the Arrma alum. cup. It wouldn't work with the M2C motor/diff. mount so I swapped it for the Hot Racing cup.

 

[Combo]

I don't recommend the Arrma alum. cup. It wouldn't work with the M2C motor/diff. mount so I swapped it for the Hot Racing cup.

Ok.. but i couldnt find any m2c parts for Mojave besides chassis bracers and a chassis.. nothing on their website..
Any other recommendations?
Thx..

 

[Brandon]

Brandon,
Should i buy 3 of these? They fit to Front-mid-rear?

Are your current stock ones broke? I would not replace the whole diff case unless needed. Just open up the current ones, check mesh replace shims, if needed, clean out old fluid and refill. Reinstall and go.