Kraton Loud cracking sound when applying heavy brake or full throttle

[Latif]

Whenever I apply a heavy brake, throw it in reverse full throttle, or pin the throttle from a standstill, I hear a loud singular cracking/snapping noise and it seems to be coming from around the centre diff. I checked the rear and centre diff and they are both perfectly fine I'm worried it could be the motor...any thoughts would be greatly appreciated!

 

[tjf]

check front diff.

 

[dpricenator]

I had a similar sound and it was the bulkhead in the rear being cracked. I had opened it up and gone over the differentials. but had not thought to check the housings.

 

[Mboss]

Also...I noticed on other cars if you have the punch setting high it can cause those symptoms. If you increased punch settings start turn back to stock to test.

 

[Hye]

Check the rear grub screw to coupler. Sometimes those get lose and it causes the ring and pinion to skip teeth. Very common.

 

[Sisson79]

I had the same sound. My front dog bone is slightly bent and hitting the servo mount

 

[Permafrost]

I have heard that sound when an input shaft cup (https://www.arrma-rc.com/part/AR310432) was worn out. I replaced the cup and the sound disappeared.

 

[Hye]

Any luck on figuring it out?

 

[Sisson79]

Not yet. I pulled it apart and sewer my front dogbone bent .I replaced that but didn't go away. I'll check the diff cup .

 

[Sisson79]

The diff cup looks brand new

 

[xSUBtRONiKx]

Towards the end of my bash session yesterday, I noticed a loud grinding cracking noise while braking. I assumed the front gear box was cracked but when I removed the front diff I noticed the input shaft cup was loose. The smaller bearing towards the cup was 'missing'. When I shimmed the diffs and replaced the bearings I used red permatex on the grub screw. So I'm thinking I messed up one of the following:

1. The bearing fell out when I pushed the input shaft through and I didn't notice.
2. The bearing exploded leaving nothing left. I didn't see any fragments in the gearbox and the outer ring was nowhere to be found
3. When I tightened the grub screw down I missed the flat spot on the shaft.
4. A combination of all three.

So I checked the gears and everything looks good. I replaced the diff in the gearbox and shimmed between the bearing and the gearbox with the Tekno shims. I replaced the missing bearing with a new one. I replaced the original drive cup, applied permatex red, and tightened it down more than I should've. I'm sure I hit the flat spot this time. I'm going to let it dry for a day before I test it out. After work tomorrow I'm going to take a look at the rear and center diffs. Most likely will not get a chance to test it until the weekend.

If your getting the cracking noise during braking and accelerating, You Should check the front and rear diffs.

 

[Iamtheoutcast]

I had a similar sound and it was the bulkhead in the rear being cracked. I had opened it up and gone over the differentials. but had not thought to check the housings.

I also had the same issue and it was comming from flex under hard acceleration or breaking because of a crack on the right side of my rear bulkhead.

 

[Mbizzle]

I'm having the same symptoms with a loud cracking noise when hitting full throttle. Not Center diff. I just put a new leopard 4092 1730kv in and I'm worried this is the culprit. I'm going to swap out with stock motor to rule this out.

 

[MikeVenezia]

I just had this problem, it wasn't really loud . but i was a missing tooth on my pinion..good luck boss