Differential shims what’s the purpose!?

[PshmokN’EM887]

So I finally had to do maintenance on all 4 rigs, I’ve been dreading it because as a noob I didn’t know what to expect.(by the way if you pay attention to disassemble part you’ll get it fast)
now to the question why does it come with one shim on one side only? and what’s the purpose of the shims ? differentials are snug I left it out because putting them in it’s a pain lol let me know before I run it in 20 min Lmaoo

 

[grihn]

Shimming allows you to to get as close to perfect as possible engagement between the ring and pinion gears, and the planetary gears within the diff. Too loose and you can strip gears, too tight and you can get binding...just right and you get a strong running rig that has no slop and doesn't strip ring gears.

 

[parcou]

@PshmokN’EM887

I've learned a lot from two people here on shimming. It's something I hard to ask a lot about, learn the hard way, and get my skills up.

The user above said it best to get the right gear mess. This is not only to put the diff back in the housing but also the input gears that connect to the driveshaft...lots of videos on that for the 6S rigs on both those, found the hard way it was important on the planetary gears inside the diff cup for the Losi DB Pro...I was screwed from the factory until I learned how to fix it right. 3S rigs like Big Rock when it comes to the spur and input gear and the crown gear in the diff housing to notice and learn how to check and recheck the shimming.

I was like DAMN! Why is shimming so important? After some bonehead mistakes as well as added stress on the rig with poor shimming or lack of knowledge to check since over usage things loosen and shimming comes more into play....Bro, I have a Ph.D. now

 

[PshmokN’EM887]

Shimming allows you to to get as close to perfect as possible engagement between the ring and pinion gears, and the planetary gears within the diff. Too loose and you can strip gears, too tight and you can get binding...just right and you get a strong running rig that has no slop and doesn't strip ring gears.

So shim the inside of the casing as well ?
So shim like it comes from factory one side on the outputcup ?

 

[slick2500]

So shim the inside of the casing as well ?
So shim like it comes from factory one side on the outputcup ?

No 2 diffs are the same, you need to add as many or few shims as are needed, could be one on each side, one on one side two on the other ect it really depends. First things first is to always build the diff dry, then check it to see if it is too loose or too tight before you add oil. The diff should feel smooth when properly shimmed, if it feels loose add shims, if it is tight and notchy remove shims.

 

[PshmokN’EM887]

So I finally had to do maintenance on all 4 rigs, I’ve been dreading it because as a noob I didn’t know what to expect.(by the way if you pay attention to disassemble part you’ll get it fast)
now to the question why does it come with one shim on one side only? and what’s the purpose of the shims ? differentials are snug I left it out because putting them in it’s a pain lol let me know before I run it in 20 min Lmaoo

 

[Senton_Prime]

Um they snug up the ring gear on the diff to the input gear.. most have a little play or "slop" some are fine.. this will snug it up good or give it a tighter "mesh"!!

 

[N.Mango]

https://www.arrmaforum.com/threads/how-to-shim-your-diff-with-pictures.7700/

 

[Engineer]

Thought I was having deja vu, but didn't you post an earlier thread about this?

https://www.arrmaforum.com/threads/differential-shims-what’s-the-purpose.49533/#post-703642

I think it was well covered in the other thread, but the 13x16 shims specifically move the crown gear either closer or further away from the input pinion depending on which side they are on. If they are on the crown gear side, it pushes the crown gear closer to the input pinion. If they are on the opposite side, it pushes the crown gear away from the input pinion. These shims are 0.2 mm thick (or maybe 0.1 mm, I can't remember) - so the difference isn't huge but it's something you will be able to feel after doing it for awhile. You want good engagement without binding.

 

[PshmokN’EM887]

Thought I was having deja vu, but didn't you post an earlier thread about this?

https://www.arrmaforum.com/threads/differential-shims-what’s-the-purpose.49533/#post-703642

I think it was well covered in the other thread, but the 13x16 shims specifically move the crown gear either closer or further away from the input pinion depending on which side they are on. If they are on the crown gear side, it pushes the crown gear closer to the input pinion. If they are on the opposite side, it pushes the crown gear away from the input pinion. These shims are 0.2 mm thick (or maybe 0.1 mm, I can't remember) - so the difference isn't huge but it's something you will be able to feel after doing it for awhile. You want good engagement without binding.

Ahhh now I get so to move clear so input gear this is the answer I’ve been waiting for thanks!

https://www.arrmaforum.com/threads/how-to-shim-your-diff-with-pictures.7700/

No you read it ! Lmao
I posted twice by mistake my bad y’all lol

 

[slick2500]

Threads merged.