[dono1]

Are the 5.12 R&P too weak for a sierra with larger tyres? 32's/33's??

[atari4x4]

are you putting the R&P into a sierra carrier or leaving them in the alloy vit junk?

[DarkHorse]

How much power you putting through them? Gearing?

The pure physics say that the smaller teeth on the gears will be easier to shear, but I've only heard of them being trashed in catastrophic alloy diff explosions.

[joeblow]

dono1 wrote:

Are the 5.12 R&P too weak for a sierra with larger tyres? 32's/33's??

When used in a Sierra cast housing no they are not weak. They require less torque to turn the wheels, so even though they are higher numerically, and the result being a smaller pinion head, because they distribute torque better with larger tyres they are the same strength if not stronger than stock Sierra jobs.

[dono1]

The one in it had a lot of wear on the pinion teeth when I put it in and I couldn't get the backlash right no matter how many times I tried to set it! It sheared some teeth off the pinion on the weekend! I just wanted to know if I was wasting my time replacing it.

[Fatzook]

Did you set the pinion depth correctly? Backlash isn't the only adjustment necessary when setting up a diff......

[joeblow]

dono1 wrote:

The one in it had a lot of wear on the pinion teeth when I put it in and I couldn't get the backlash right no matter how many times I tried to set it! It sheared some teeth off the pinion on the weekend! I just wanted to know if I was wasting my time replacing it.

That has been run with a loose pinion or no oil. And also what Fat said.

[tanshi]

I cant speak for 5.12 diffs but i know that 4.6s are which should be theoretically stronger.
my old man had destroyed a few 4.6 sets.

even then it can be put down to how you drive it.

[Fatzook]

tanshi wrote:

I cant speak for 5.12 diffs but i know that 4.6s are which should be theoretically stronger.
my old man had destroyed a few 4.6 sets.

even then it can be put down to how you drive it.

Yeah this isn't right. Sounds like there may be a larger issue at hand ( other than your old mans heavy right boot )

[tanshi]

not sure what it could be then. car is an auto so should be softer on the gear.
it is running 33s where most people dont.

the only other thing i can put it down to is heavy left foot braking that we do alot of in trophy class

[dono1]

Ill put it down as a worn teeth contributing to the teeth shearing. The front I put in has lasted..

Pinion depth was set right, it did have an oil leak cause I had to put in a gasket(I ran out of goo). Maybe it got too hot?