Kraton Broke my rear input gear

[Danny_Kraton]

Hi guys,

So i've broken my rear my rear input gear, 4 teeth missing, looks like its done a bit of damage to my rear diff gear too so i'll be replacing both.

I've seen people break gears inside the diff but i've never seen anyone actually brake the input gear, was this just a fluke incident or is there something i can do to prevent this from happening again? i plan to shim the diffs while im doing the repairs, is there a shim i can put on the outside to help the input gear and the main diff gear to stay meshed?

Cheers
Danny

 

[MeesterC]

Hi guys,

So i've broken my rear my rear input gear, 4 teeth missing, looks like its done a bit of damage to my rear diff gear too so i'll be replacing both.

I've seen people break gears inside the diff but i've never seen anyone actually brake the input gear, was this just a fluke incident or is there something i can do to prevent this from happening again? i plan to shim the diffs while im doing the repairs, is there a shim i can put on the outside to help the input gear and the main diff gear to stay meshed?

Cheers
Danny

You may have got one that had a little to much play in it. Shimming the differentials makes them bullet proof. Yes there are shims that can be used to shim the input gear. There are several threads about this and a few of them even have the description and part numbers of the shims needed. Sorry to hear about it breaking but once you shim them you won't have to worry anymore.

 

[rag6]

This shows

Hi guys,

So i've broken my rear my rear input gear, 4 teeth missing, looks like its done a bit of damage to my rear diff gear too so i'll be replacing both.

I've seen people break gears inside the diff but i've never seen anyone actually brake the input gear, was this just a fluke incident or is there something i can do to prevent this from happening again? i plan to shim the diffs while im doing the repairs, is there a shim i can put on the outside to help the input gear and the main diff gear to stay meshed?

Cheers
Danny

In this vid:

He puts a shim on outside of the bearings if that is what you need.

 

[ParkRacing]

You may have got one that had a little to much play in it. Shimming the differentials makes them bullet proof. Yes there are shims that can be used to shim the input gear. There are several threads about this and a few of them even have the description and part numbers of the shims needed. Sorry to hear about it breaking but once you shim them you won't have to worry anymore.

Bullet proof, no such thing, more durable yes. Here is my center "bullet proof" yesterday.
Fortunately I have learned to keep spare diff parts on hand, broke rear bullet proof diff last weekend. Be sure to replace the little pins that go thru the output shafts, behind the sun gear with 2.2mm drill blanks, Best mod, those would always break and the sun gear would be frozen on!
What we need is hardened diff internals.

This is Rich Duperbash's comment on one of my threads yesterday showing my broken gears.

I haven't stripped any internal diff gears, just broken lots of planetary gears, a few pins, and broken teeth off my crown and input gears on probably all my Arrmas at some point, front and rear...Lol. Are those sattelite gears stripped out? Sorta hard to tell with the sludge still on.

 

[Crash]

I find most issues from broken internal gears was the four screw holding the diff together backing out. Using HR aluminum diff cups and blue loc tite keeps them from backing out and keeping everything together and tight. Along with shimming the diffs of course. With 500k oil in my center diff it has never been so strong or dependable. Running 6s and hard on the throttle!

 

[Danny_Kraton]

awesome thanks for the advice guys. i'll shim the diffs and i've ordered spares of everything, and i'll definitely be adding a shim to the outside to try minimise any movement between the input gear and the main gear

 

[jonUF02]

I put Mugen MBX7 internal gears, shims, and output drive cups, along with the HR aluminum diff cup. About as bulletproof as its going to get.

 

[Crash]

I put Mugen MBX7 internal gears, shims, and output drive cups, along with the HR aluminum diff cup. About as bulletproof as its going to get.

I like those output drive cups. Do they wear fast.

 

[jonUF02]

Haven't had them long, but definitely better quality.

 

[dpricenator]

I put Mugen MBX7 internal gears, shims, and output drive cups, along with the HR aluminum diff cup. About as bulletproof as its going to get.

ANY CHACE for a couple part numbers or links to the gears and cups? THaks

 

[jonUF02]

I bought the entire diff assembly from Dollarhobbyz.com in pieces it would cost a lot more. Threw aside the Mugen plastic cup and gear. Need the Arrma cup or HR cup and spur, as well as the metal cross pins holding the 4 planetary gears.

 

[Danny_Kraton]

damn that diff set up looks awesome, wish i saw that before i bought all the parts!

 

[jonUF02]

damn that diff set up looks awesome, wish i saw that before i bought all the parts!

Just posted full details and pics in the drivetrain section of the forum.

 

[RcDaddy]

I hear ya on no such thing as bulletproof. I had my diffs and out drives shimmed and after a couple months both diffs and pinions were shot. Replaced rear and two runs later that one rounded out again. WTF I can't afford much more!!

 

[Crash]

Not to start an ego fire about whos good at what. But its all about the builder IMHO. My rear diff is stock accept the shims. No broken gears,leaks or strips. Going on 4 months at 6s. I see a lot stripped pinion talk as well. Once again all about the builder. Im on stock pinions for 4 months and they still look great. Yes there are faulting parts but if you keep chewing gears and blowing out diffs IMHO thats human error!

 

[RcDaddy]

Dude it's not like I'm machining parts and building rockets for NASA!!!

 

[Crash]

Ok............

 

[jonUF02]

Not to start an ego fire about whos good at what. But its all about the builder IMHO. My rear diff is stock accept the shims. No broken gears,leaks or strips. Going on 4 months at 6s. I see a lot stripped pinion talk as well. Once again all about the builder. Im on stock pinions for 4 months and they still look great. Yes there are faulting parts but if you keep chewing gears and blowing out diffs IMHO thats human error!

Honestly, I have never broken or stripped a Kraton diff. I am running my rear 100% stock install right now. I thought 8 stripped the front when I did this, but it was just the set screw loose on the cup to the input shaft.

I did have a problem with the center diff cup. The metal insert broke loose from the plastic cup, so I replaced that with the HR aluminum cup and all stock internals.

 

[ParkRacing]

Not to start an ego fire about whos good at what. But its all about the builder IMHO. My rear diff is stock accept the shims. No broken gears,leaks or strips. Going on 4 months at 6s. I see a lot stripped pinion talk as well. Once again all about the builder. Im on stock pinions for 4 months and they still look great. Yes there are faulting parts but if you keep chewing gears and blowing out diffs IMHO thats human error!

IMHO you should build diffs for the rest of us because apparently we are not worthy...
Nothing is bullet proof and the amount of power we run thru cars is insane.

 

[Crash]

Ok.......