I broken the rear dog bone in my kraton 6s

[Rodrigol]

Hello!!!

Any one know what could be the problem or just fatige material?

I recently did the rear differential silicone change, but only got 7,000. ¿Could this be the problem? (It Broke accelerating not jumping)
I ran in 6s with speed pinion.
Thanks for yours opinions!!

 

[SrC]

Were you running the speed gear in the rough off road or on road? ( not supposed to off road) Off road probably caused this. But dog bone cross pins do break... Rare in my opinion. I never broke one and I beat the crap out of mine. But I don t run tall gearing in the dirt. The much higher RPM's will overheat the electrics and also brick the drivetrain ( rear driveshaft) as you just did.
FWIW. I am running 60k front-500k center-20k Rear. That's what I use in my Kraton. Noto, and Mojave. and my Hybrid Mojave chassis 1/7 Typhon. Works the best for my 6s Off road rigs. Driver error can also cause broken dog pins.... "On throttle" landing. Very bad for all the drivetrain parts.

 

[Rodrigol]

Were you running the speed gear in the rough off road or on road? ( not supposed to off road) Off road probably caused this. But dog bone cross pins do break... Rare in my opinion. I never broke one and I beat the crap out of mine. But I don t run tall gearing in the dirt. The much higher RPM's will overheat the electrics and also brick the drivetrain ( rear driveshaft) as you just did.
FWIW. I am running 60k front-500k center-20k Rear. That's what I use in my Kraton. Noto, and Mojave. and my Hybrid Mojave chassis 1/7 Typhon. Works the best for my 6s Off road rigs. Driver error can also cause broken dog pins.... "On throttle" landing. Very bad for all the drivetrain parts.

I drove on sand and a bit of soft dirt ... the car was doing a lot of wheelie. I thought I should just watch only the motor and esc temperature. Could be the problem the speed pinion, Im checking again the dog bone, and it's a little bent (possible drive shaft lock just as you said) so... wich pinion would be adequate? maybe a 13 tooth? ¿the silicone is discarted?

thanks again for your help!!

 

[SrC]

You were in the dirt. Ok part of the problem. Wheelies didn't help at all in the dirt no less with the speed gear. Drop your pinion down. Start with the stocker and work your way up maybe 2 teeth bigger at a time. I have complete sets here. Not many do. A good set of Tekno pinions will cost you. But that s how I tune my gearing, with a whole set available. Did you put bigger tires over stockers? Bigger will be like putting too big a gear on also. Bigger tires affects the final drive ratio.

 

[Rodrigol]

You were in the dirt. Ok part of the problem. Wheelies didn't help at all in the dirt no less with the speed gear. Drop your pinion down. Start with the stocker and work your way up maybe 2 teeth bigger at a time. I have complete sets here. Not many do. A good set of Tekno pinions will cost you. But that s how I tune my gearing, with a whole set available. Did you put bigger tires over stockers? Bigger will be like putting too big a gear on also. Bigger tires affects the final drive ratio.

ok about the pinion!!. now .. about the tires you are right again, I mounted the duratrax FAZE MT, is more bigger than the copperhead 2. The dog bone broke after a short time of use. Pinion and tires fatal mix.

 

[SrC]

Big tires extra weight alone can be one problem aside from the final drive that a taller tire makes. Some tires can weight 1/3 more than stock in some cases (multiplied by 4) There are really 2 distinct issues independent of each other, but combined adds load to the drivetrain, and extra heat to the motor. Added rotating mass and weight and larger diameter roll out.

 

[jkflow]

Your 7k diff fluid can be blamed as well. Stock is 10k and you should only go higher.

 

[Rodrigol]

Big tires extra weight alone can be one problem aside from the final drive that a taller tire makes. Some tires can weight 1/3 more than stock in some cases (multiplied by 4) There are really 2 distinct issues independent of each other, but combined adds load to the drivetrain, and extra heat to the motor. Added rotating mass and weight and larger diameter roll out.

Ok, first I will change the pinion and get your diff fluid combination. im will checking the drive shaft temp with this changes. The tires are new, I hope I can use them without more problems

Thanks a lot for your help!!!