Kraton Kraton v5 front bulkhead cover

Sir Marz

Member
Messages
31
Reaction score
12
Hey guys hope your all well this holiday season ....

So I've had a v5 kraton for about a year now and I keep breaking the front bulkhead cover when the front diff gets put under pressure ... it stripps the ring and input gears....
Seems to always go on the bottom left .

Any suggestions on how to fix the issue ...

I was looking at getting the metal front cover ...
Or should I get the full metal bulkhead. ?

Would either of them solve the problem?

Should I get metal diffs with that ?

It's a v5 kraton with a 1717 1650kv Mmx8s 21t pinion standard centre diff with a metal case .

60k rear 500k centre 60k front
 

KevinC

Flyboy, Cat Hoarder, Booze Junkie, Snail Wrangler
Lifetime Premium!
Premium Member
Build Thread Contributor
Messages
2,033
Reaction score
3,098
Location
Brantford,Ontario
Arrma RC's
  1. Fireteam
  2. Kraton 8S
  3. Kraton 6s
  4. Kraton EXB
  5. Mojave EXB
  6. Talion
  7. Talion EXB
Mmmmm….
Your bulkhead cover wouldn’t be the cause of your gears stripping. What happens to the cover? Can you post a picture of the damage?
Your diff may not be shimmed properly to sit in the bulkhead, any side to side movement is undesirable. I’m too lazy to look at the exploded view……is there a shim that is supposed to sit outside the bearing on the ring gear side?
 
Last edited:

Sir Marz

Member
Messages
31
Reaction score
12
Where the screw bolts in it cracks ... if the lid looses a mounting its not holding the diff down tightly enough....
Under heavy breaking the diff shifts and the input gear eats into the plastic diff and slips the ring .... before I removed the red cap at the end of the a arm the dog bone would also pop out

Or perhaps I'm wrong and it's the internal gears that's gone .....

Altho I didn't see any real wear on any of the gears ... which is why I'm still thinking bulkhead cover ...

I opened the centre diff and front diff ... as when I heard the noise.... I held down the front and the rear would spin but the front would make the noise.... if I held down the rear the front would spin but no noise ....

The centre diff sort of smelt burnt .... but the gears look perfect ... and I couldn't see any wear.

The only gear I could see wear on is the sun gear on the diff but only slightly worn down .

There are shims on the gear side of the diff ... and the internal gears have an extra shim ...
 

KevinC

Flyboy, Cat Hoarder, Booze Junkie, Snail Wrangler
Lifetime Premium!
Premium Member
Build Thread Contributor
Messages
2,033
Reaction score
3,098
Location
Brantford,Ontario
Arrma RC's
  1. Fireteam
  2. Kraton 8S
  3. Kraton 6s
  4. Kraton EXB
  5. Mojave EXB
  6. Talion
  7. Talion EXB
Well, to rule out the obvious……are you torquing down the bulkhead cover so much you are cracking the gearbox? Start with a new stock gearbox first, if you’re still having that problem try some metal gearboxes. They’re very nice and no shortage of manufacturers making them.

cheers,
kev
 

Sir Marz

Member
Messages
31
Reaction score
12
Well, to rule out the obvious……are you torquing down the bulkhead cover so much you are cracking the gearbox? Start with a new stock gearbox first, if you’re still having that problem try some metal gearboxes. They’re very nice and no shortage of manufacturers making them.

cheers,
kev
The gearbox isn't cracking ... its the gearbox cover ... if there's pressure on the diff it would push away from the input gear ....like hard breaking would put torque on the diff ... pushing it out ever so slightly ... enough to make the gears slip ....

How would I tell if the internal diff gears are stripped ....

Looking at them they look perfect ...


Please note I've opened them up and had a look at everything before I left for vacation.... so im unable to take pictures ... altho it's not the first time this is happening.... the first time ... the centre diff exploded .... so I replaced the gears and the diff cover .... it explodes a second time ... so I put the hot racing diff case and that held up for a good while ... then that exploded too but lucky just the screws napped inside ... they were nice enough to come out easily.... replaced the screws and it's still good ...

I would agree that I'm over torqued if the same thing didn't happen when I just got the truck .
 

SrC

RC is a lifestyle choice
Lifetime Premium!
Premium Member
Excellence Award
Hospitality Award
Build Thread Contributor
Messages
17,788
Reaction score
22,673
Location
Queens, NYC
Arrma RC's
  1. Fireteam
  2. Infraction
  3. Limitless
  4. Kraton 6s
  5. Mojave
  6. Notorious
  7. Outcast 6s
  8. Typhon TLR
Usually the screws will bend and/or strip the plastic. The Plastic can split also at the lower screw.. But from my experience, you need a decent Bumper. Because driver error is getting the best of your front end. Have you considered using the EXB basher bumper? The stock RTR V5 bumper is barely even a bumper of sorts. If that is what you still have.
I would consider a HR alloy bulkhead Cover first if anything, provided you have decent Front Bumper. The alloy cover will keep the whole plastic bulkhead square and straighter with hard impacts. Less chance for Main gear/Input gear issues. Proper main gear shimming is always a given. But the alloy cover or $complete$ Alloy Bulkhead is just a band-aid approach IMHO. Watch your driving better. I have been guilty of this, but have learned to drive better protecting the front more, and have no recent issues with my front bulkhead impacts. And I recently installed the EXB basher bumper on my V4 RTR Kraton. I was using a T-Bone bumper. It finally gave out. T-Bone went out of business. Many like the EXB bumper best these days. There is also RPM bumpers FWIW.

https://www.amazon.com/ARRMA-Super-...Arrma+EXB+basher+bumper&qid=1671517036&sr=8-1
 
Last edited:

Sir Marz

Member
Messages
31
Reaction score
12
The gearbox isn't cracking ... its the gearbox cover ... if there's pressure on the diff it would push away from the input gear ....like hard breaking would put torque on the diff ... pushing it out ever so slightly ... enough to make the gears slip ....

How would I tell if the internal diff gears are stripped ....

Looking at them they look perfect ...


Please note I've opened them up and had a look at everything before I left for vacation.... so im unable to take pictures ... altho it's not the first time this is happening.... the first time ... the centre diff exploded .... so I replaced the gears and the diff cover .... it explodes a second time ... so I put the hot racing diff case and that held up for a good while ... then that exploded too but lucky just the screws napped inside ... they were nice enough to come out easily.... replaced the screws and it's still good ...

I would agree that I'm over torqued if the same thing didn't happen when I just got the truck .
The first two times it's happened when the gearbox cover broke, the front left drivesharft would pop out the diff cup ... common problem with those red caps on there . Then I removed the red caps and it's like the truck became so much more durable ...

I did do some heavy bashing when the gearbox cover broke again this time so I don't blame the plastic ....

If I just replaced the plastic cover for a metal cover .... would that make the screws just strip out instead ...

If the full metal gearbox case is on there wouldn't that be too heavy ?

I don't generally put on metal parts unless it's absolutely necessary as it might seem like 10 or 20gs heavier.... but under force that's multiplied... so for weight purposes if it's not necessary ... also metal bends but plastic bends back
Usually the screw will bend and/or strip the plastic. The Plastic can split also at the screw.. But from my experience, you need a decent Bumper. Because driver error is getting the best of your front end. Have you considered using the EXB basher bumper? The stock RTR V5 bumper is barely even a bumper of sorts. If that is what you still have.
I would consider a HR alloy Cover first if anything, provided you have decent Front Bumper. The alloy cover will keep the whole plastic bulkhead square and straighter with hard impacts. Less chance for Main gear/Input gear issues. Proper shimming is always a given. But the alloy cover or $complete$ Alloy Bulkhead is just a bandaid approach IMHO. Watch your driving better. I have been guilty of this, but have learned to drive better protecting the front more, and have no recent issues with my front bulkhead impacts. And I recently installed the EXB basher bumper on my V4 RTR Kraton. I was using a T-Bone bumper. It finally gave out. T-Bone went out of business. Many like the EXB bumper best these days. There is also RPM bumpers FWIW.
I have an rpm front bumper on there ... when the gears started stripping is when I flipped over and was really far from the truck so I went in reverse then on the throttle .... it popped on the front wheels again but thats when I heard it .. as the front wheels made contact with the grass ... so definitely user error as these aren't made for self righting.... but as the front wheels touched im sure that's when the front cover gave in and the diff had enough space to move .... the input gear teeth was patterned into the plastic diff case . So its definitely shifted inside there .

So far I havnt broke any gears ..

I have a felony and the only thing I've ever replaced was tyres , the frint lip (worn out)... and the esc and motor to castle ....
 
Last edited:

SrC

RC is a lifestyle choice
Lifetime Premium!
Premium Member
Excellence Award
Hospitality Award
Build Thread Contributor
Messages
17,788
Reaction score
22,673
Location
Queens, NYC
Arrma RC's
  1. Fireteam
  2. Infraction
  3. Limitless
  4. Kraton 6s
  5. Mojave
  6. Notorious
  7. Outcast 6s
  8. Typhon TLR
The diffs last much longer with the on-road rigs.. Like my Lim and Infr. Speed run them only.
I prefer plastic bulkheads. I just replace them if they wear out. Many use alloys. But they too will get damaged from driver error. And expensive to replace when they do. Depends how you bash and drive.
At some point the plastic bulkheads will just wear out. Very cheap to replace them. What I do.
I would only consider the HR covers first and even the "sway bar mount" on top of the cover. Keeps the sway bars working better. Just me.
 

Sir Marz

Member
Messages
31
Reaction score
12
The diffs last much longer with the on-road rigs.. Like my Lim and Infr. Speed run them only.
I prefer plastic bulkheads. I just replace them if they wear out. Many use alloys. But they too will get damaged from driver error. And expensive to replace when they do. Depends how you bash and drive.
At some point the plastic bulkheads will just wear out. Very cheap to replace them. What I do.
I would only consider the HR covers first and even the "sway bar mount" on top of the cover. Keeps the sway bars working better. Just me.
Thanks bud for all the assistance and advice ... ill go with that ... how do the exb diffs compare to the standard diffs .... is it considered a stronger upgrade ?
 

SrC

RC is a lifestyle choice
Lifetime Premium!
Premium Member
Excellence Award
Hospitality Award
Build Thread Contributor
Messages
17,788
Reaction score
22,673
Location
Queens, NYC
Arrma RC's
  1. Fireteam
  2. Infraction
  3. Limitless
  4. Kraton 6s
  5. Mojave
  6. Notorious
  7. Outcast 6s
  8. Typhon TLR
That's a whole other ball of wax. :giggle:
EXB diffs are LSD. (Limited slip). Harder to set up and tune, using 2 types of stages. And with thinner oils, with slip plates etc.. I don't run them. I stay with the RTR "Open" Diffs. Serve me well. I use 60k front/ 500k center/ 30k Rear oils in my Open diffs. Many here do this. Stock oil is just too thin. Food for thought.
But the EXB Main Gear and Input gears themselves are stronger no doubt. And if you buy the Optional EXB Open shim kits, they can be made to be Non-LSD. Which many do. They cost a bit more also. That's your call.:cool:
Do a search here on AF . Many threads in regards to LSD diffs. Are they really an upgrade??? That depends who you are asking.;) You can always experiment and decide for yourself.:) EXB LSD 29mm diffs will drop right into the standard bulkheads FWIW.
Some have complained of Fitment issues when running 29mm EXB diffs with the full alloy Upgrade brand Bulkheads.
 
Last edited:

Sir Marz

Member
Messages
31
Reaction score
12
That's a whole other ball of wax. :giggle:
EXB diffs are LSD. (Limited slip). Harder to set up and tune, using 2 types of stages. And with thinner oils, with slip plates etc.. I don't run them. I stay with the RTR "Open" Diffs. Serve me well. I use 60k front/ 500k center/ 30k Rear oils in my Open diffs. Many here do this. Stock oil is just too thin. Food for thought.
But the EXB Main Gear and Input gears themselves are stronger no doubt. And if you buy the Optional EXB Open shim kits, they can be made to be Non-LSD. Which many do. They cost a bit more also. That's your call.:cool:
Do a search here on AF . Many threads in regards to LSD diffs. Are they really an upgrade??? That depends who you are asking.;) You can always experiment and decide for yourself.:) EXB LSD 29mm diffs will drop right into the standard bulkheads FWIW.
Some have complained of Fitment issues when running 29mm EXB diffs with the full alloy Upgrade brand Bulkheads.
May I ask why you run thicker oil in the front and thinner oil in the rear ...
 

SrC

RC is a lifestyle choice
Lifetime Premium!
Premium Member
Excellence Award
Hospitality Award
Build Thread Contributor
Messages
17,788
Reaction score
22,673
Location
Queens, NYC
Arrma RC's
  1. Fireteam
  2. Infraction
  3. Limitless
  4. Kraton 6s
  5. Mojave
  6. Notorious
  7. Outcast 6s
  8. Typhon TLR
With a 4x4 rig, you want the front end to pull harder than the the rear end pushes. This reduces/limits any front end understeer/ pushing. Easier to drive and steer, gain more steering control when bashing hard. All this is relative to your chosen center differential oil. Much is trial and error and how you like to drive.
Factory RTR 6s stock oil is only 10k at both front and rear. Stock center diff oil is only 100k. FWIW.
For smaller technical confined tracks running 3s or 4s lipos these oils might work better.
 
Last edited:

Sir Marz

Member
Messages
31
Reaction score
12
That's a whole other ball of wax. :giggle:
EXB diffs are LSD. (Limited slip). Harder to set up and tune, using 2 types of stages. And with thinner oils, with slip plates etc.. I don't run them. I stay with the RTR "Open" Diffs. Serve me well. I use 60k front/ 500k center/ 30k Rear oils in my Open diffs. Many here do this. Stock oil is just too thin. Food for thought.
But the EXB Main Gear and Input gears themselves are stronger no doubt. And if you buy the Optional EXB Open shim kits, they can be made to be Non-LSD. Which many do. They cost a bit more also. That's your call.:cool:
Do a search here on AF . Many threads in regards to LSD diffs. Are they really an upgrade??? That depends who you are asking.;) You can always experiment and decide for yourself.:) EXB LSD 29mm diffs will drop right into the standard bulkheads FWIW.
Some have complained of Fitment issues when running 29mm EXB diffs with the full alloy Upgrade brand Bulkheads.
May I ask why you run thicker oil in the front and thinner oil in the rear ... that
That's a whole other ball of wax. :giggle:
EXB diffs are LSD. (Limited slip). Harder to set up and tune, using 2 types of stages. And with thinner oils, with slip plates etc.. I don't run them. I stay with the RTR "Open" Diffs. Serve me well. I use 60k front/ 500k center/ 30k Rear oils in my Open diffs. Many here do this. Stock oil is just too thin. Food for thought.
But the EXB Main Gear and Input gears themselves are stronger no doubt. And if you buy the Optional EXB Open shim kits, they can be made to be Non-LSD. Which many do. They cost a bit more also. That's your call.:cool:
Do a search here on AF . Many threads in regards to LSD diffs. Are they really an upgrade??? That depends who you are asking.;) You can always experiment and decide for yourself.:) EXB LSD 29mm diffs will drop right into the standard bulkheads FWIW.
Some have complained of Fitment issues when running 29mm EXB diffs with the full alloy Upgrade brand Bulkheads.
It just seems a little odd since you
With a 4x4 rig, you want the front end to pull harder than the the rear end pushes. This reduces/limits any front end understeer/ pushing. Easier to drive and steer, gain more steering control when bashing hard. All this is relative to your chosen center differential oil. Much is trial and error and how you like to drive.
Factory RTR 6s stock oil is only 10k at both front and rear. Stock center diff oil is only 100k. FWIW.
For smaller technical confined tracks running 3s or 4s lipos these oils might work better.
I get the pulling part .... wouldn't that be a more loose centre diff and a tighter rear medium front

The stiff rear allows the rear to swing out ... and the medium front allows the outer wheel to spin more when cornering?
 

morrjr71

The Old Guy
Premium Member
Military Veteran
Build Thread Contributor
Messages
2,093
Reaction score
3,226
Location
Mechanicsville, MD
Arrma RC's
  1. Kraton 6s
  2. Typhon 3s
  3. Infraction 4x4

djrahbee

Premium Member!
Premium Member
Build Thread Contributor
Messages
630
Reaction score
1,128
Location
VA
Arrma RC's
  1. Infraction
  2. Kraton 8S
  3. Kraton 6s
  4. Kraton EXB
  5. Mojave
  6. Outcast 4s

Sir Marz

Member
Messages
31
Reaction score
12
Do you know of any thread links speaking of lsd diff oils please.... im just curious.... to know if I want to change over .... all this diff talk has me on the fence of staying stock or moving to the lsd ...

For my preference the 60k front and rear wasn't thick enough ... so maybe the lsd is what I need
Also can you burn diff oil ? When I opened my centre diff it smelt burnt ...
If $ isn't an issue I would go with these. I have 2 on the way for my K6! I haven't had the screws strip out of the cover but I have had them pull out the bottom of the bulkhead through the chassis. Vitavon is supposed to be top of the line aluminum parts so I personally am gonna go with these.

https://www.ebay.com/itm/284279923192?hash=item42306761f8:g:OLUAAOSwnwVi2A5E&amdata=enc:AQAHAAAA4M9pl3nWNEHHDcI5X241arJtehxpAoUjUf7WgIosPkIRcRBCL/LkzOj82nCGdKo6Z2CFhk/H76Mvv0cAxZm1FNn2TcV80KfTqIFjLHjKUKiB2itERwQET8ZK0+GJtvx9SfHGPZJuwSPhshWYW3XvsmwKdMjjjYqotRb0nze+wFItNiCpHiQ5j9HUCEiJno/oIaMVJ30eG6R+Cs7C73QlxSzHV7Drpst5Jmc5JGJ1H+FMcTlUcg8khbDttp/VJ/FciNggEA/TdK/8qz2IdY1YK5gb3/gdY1lzvy5Q0R2Yc4o0|tkp:BFBMrpCtgaZh
The problem with ebay is the shipping, im in south Africa ... if the seller ships through the post its going to take forever to come and sometimes shipping makes the product not worth it if it's through a third-party... I usually only buy things on Amazon as they ship fairly quickly and if I have any issues they refund no stress .
 
Last edited:

KevinC

Flyboy, Cat Hoarder, Booze Junkie, Snail Wrangler
Lifetime Premium!
Premium Member
Build Thread Contributor
Messages
2,033
Reaction score
3,098
Location
Brantford,Ontario
Arrma RC's
  1. Fireteam
  2. Kraton 8S
  3. Kraton 6s
  4. Kraton EXB
  5. Mojave EXB
  6. Talion
  7. Talion EXB
Stay with the stock RTR open diffs if you can, its just way easier and less moving parts (which is always good).
I own 4 rigs with LSD and they can be pretty finicky. If I had a choice I'd run all open and may convert over in the future.

Lsd diffs require thinner oils, but they come with oil too thin in my opinion. For the front I mix 20-30K, center mix100-200K, rear mix 10-20K.

cheers,
kev
 

djrahbee

Premium Member!
Premium Member
Build Thread Contributor
Messages
630
Reaction score
1,128
Location
VA
Arrma RC's
  1. Infraction
  2. Kraton 8S
  3. Kraton 6s
  4. Kraton EXB
  5. Mojave
  6. Outcast 4s
Do you know of any thread links speaking of lsd diff oils please.... im just curious.... to know if I want to change over .... all this diff talk has me on the fence of staying stock or moving to the lsd ...

For my preference the 60k front and rear wasn't thick enough ... so maybe the lsd is what I need
Also can you burn diff oil ? When I opened my centre diff it smelt burnt ...

The problem with ebay is the shipping, im in south Africa ... if the seller ships through the post its going to take forever to come and sometimes shipping makes the product not worth it if it's through a third-party... I usually only buy things on Amazon as they ship fairly quickly and if I have any issues they refund no stress .
Mine were shipped from China. FWIW Just gottem today.

IMG-3260.jpg
 
Top