Granite Constant Diff Problems

[Prisma]

Hey everyone,
I'm starting to be worried about how often my stock front diff on my Granite strips a tooth or two. I've rebuilt it too weeks ago, ran about 3 packs through it and the input gear has a tooth slightly shorter than the rest, causing it to slip once in a while.
Now the infuriating part: I'm intentionally loosening my slipper, accelerating so slowly I've not pulled a wheelie in months and yet, the front diff ONLY breaks all the time.
I know this might sound like a stupid question, but what am I doing wrong? There is a bit more resistance in the front diff, than in the back one, although I just passed it off as it needing to break in a bit.
I've applied plenty of grease, made sure the yoke isn't too tight, because then it would lock up.
Is there a way I can make the gears last longer? Any replies very appreciated

 

[Yas]

Shims if the mesh is too tight, and from the factory they usually are, the gears wear prematurely. You should always tighten the yoke - if doing so binds the gears, you need to shim the ring gear away from the pinion

 

[Prisma]

Shims if the mesh is too tight, and from the factory they usually are, the gears wear prematurely. You should always tighten the yoke - if doing so binds the gears, you need to shim the ring gear away from the pinion

I've rebuilt it now, it doesn't bind when I tighten it, it's just not as smooth as the worn down rear one.
I did use shims though, in the same configuration the rear diff has

 

[GRC]

That's unusual. The front diff takes much less abuse than the rear. Most people have problems with the rear. My front diff lasted over a year. I went though several rear diffs in that time.

The shim comes from the factory on the ring gear side. If you're having trouble, don't use the same configuration. Switch the shim to the opposite side. It loosens up the mesh and will make the diff and input gear roll more easily.

If that doesn't help, check the metal gears inside the diff carefully for any nicks or chips that may be getting jammed up. Then make sure all your bearings are good. The bearing inside the diff, the bearings on the sides of the diffs and your wheel bearings.

 

[Prisma]

That's unusual. The front diff takes much less abuse than the rear. Most people have problems with the rear. My front diff lasted over a year. I went though several rear diffs in that time.

The shim comes from the factory on the ring gear side. If you're having trouble, don't use the same configuration. Switch the shim to the opposite side. It loosens up the mesh and will make the diff and input gear roll more easily.

If that doesn't help, check the metal gears inside the diff carefully for any nicks or chips that may be getting jammed up. Then make sure all your bearings are good. The bearing inside the diff, the bearings on the sides of the diffs and your wheel bearings.

Thanks for the reply!
Actually up until now, I was running it with the shim on the other side, to keep it loose. Maybe that was the problem?
And yes, it's weird that the front diff, of all things is breaking the most

 

[jondilly1974]

Hey everyone,
I'm starting to be worried about how often my stock front diff on my Granite strips a tooth or two. I've rebuilt it too weeks ago, ran about 3 packs through it and the input gear has a tooth slightly shorter than the rest, causing it to slip once in a while.
Now the infuriating part: I'm intentionally loosening my slipper, accelerating so slowly I've not pulled a wheelie in months and yet, the front diff ONLY breaks all the time.
I know this might sound like a stupid question, but what am I doing wrong? There is a bit more resistance in the front diff, than in the back one, although I just passed it off as it needing to break in a bit.
I've applied plenty of grease, made sure the yoke isn't too tight, because then it would lock up.
Is there a way I can make the gears last longer? Any replies very appreciated

View attachment 161706

I would replace that yoke, or swap the front and rear assemblies and see if the problem follows the yoke. If you are stripping the front only, that means it's likely happening under braking, not acceleration. Try lowering your brake setting a little too.

 

[Prisma]

I would replace that yoke, or swap the front and rear assemblies and see if the problem follows the yoke. If you are stripping the front only, that means it's likely happening under braking, not acceleration. Try lowering your brake setting a little too.

That's true, didn't think that could be the issue. I do break quite a lot and it's set so tight it rolls over quite often. That would also explain why only one tooth breaks at a given time

 

[jondilly1974]

That's true, didn't think that could be the issue. I do break quite a lot and it's set so tight it rolls over quite often. That would also explain why only one tooth breaks at a given time

Yep! All sounds like it makes sense to me. If you are doing stoppies often, your brake is way too high.

 

[GRC]

Thanks for the reply!
Actually up until now, I was running it with the shim on the other side, to keep it loose. Maybe that was the problem?
And yes, it's weird that the front diff, of all things is breaking the most

If switching the shim didn't help. The yoke could be a problem. The yoke actually does look loose in the photo. Also check the gears and the bearings as I mentioned.

 

[BulletRCs_NZ]

A good thread. My problem is the opposite I'm continually doing rear diffs, in multiple 3s vehicles but these replies give me hope. I'm going to try different shim configurations.

 

[Prisma]

If switching the shim didn't help. The yoke could be a problem. The yoke actually does look loose in the photo. Also check the gears and the bearings as I mentioned.

I did rebuild it completely two weeks ago, so I replaced the entire main diff case, including the oil and stuff. The gears inside are in great condition, although the diff itself is leaking quite a bit due to the main isolation pad missing

 

[slick2500]

You could try the Hot Racing yolks, the plastic ones can flex under load.

 

[jondilly1974]

You could try the Hot Racing yolks, the plastic ones can flex under load.

The chassis and diff tower should not allow the yoke to flex, as long as the screws holding it all together aren't loose or stripped, right? The chassis and towers are much stiffer and shouldn't flex at all.

 

[slick2500]

The chassis and diff tower should not allow the yoke to flex, as long as the screws holding it all together aren't loose or stripped, right? The chassis and towers are much stiffer and shouldn't flex at all.

They are plastic believe it or not they flex too.

 

[GRC]

Yes, I think reducing flex is a big part of saving the diffs, the rear more than the front. The Hot Racing yoke and tower to tower brace has helped my rear diff last longer. If you press both shock towers toward each other, you can feel the flex. With the tower to tower brace, that flex is gone. I may still end up getting the metal crown/input gear, but we'll see if the plastic holds up.

 

[BulletRCs_NZ]

I may still end up getting the metal crown/input gear, but we'll see if the plastic holds up.

I did this, going metal for my BR. Will be another 3 weeks before it arrives but it's the start of building my Bullet proof Big Rock.

 

[chazekxt46]

i run hr diff yoke's ft and rear