HP 30 pattern check

[Woodrow]

I have finally gotten to work on my new axles starting with the front. This is a ‘98 XJ HP 30 with a 30 spline eaton E locker carrier and revolution 5.13 reverse cut gears. Pinion rotational torque and backlash are within spec. I have started with a total of 0.081 inches of pinion shim (0.032 slinger under the inner bearing and 0.049 under the race):

I think I’m shallow. So, since this is my first pattern, I was going to increase the shim stack under the inner race by 0.010” in an attempt to bracket.

 

[lBasket]

Living my axle dreams over here. Hopefully this turns into a good reference for when I do the exact same thing later

 

[Woodrow]

Living my axle dreams over here. Hopefully this turns into a good reference for when I do the exact same thing later

yeah, buddy

 

[hosejockey61]

I have finally gotten to work on my new axles starting with the front. This is a ‘98 XJ HP 30 with a 30 spline eaton E locker carrier and revolution 5.13 reverse cut gears. Pinion rotational torque and backlash are within spec. I have started with a total of 0.081 inches of pinion shim (0.032 slinger under the inner bearing and 0.049 under the race):
View attachment 582007
View attachment 582008
I think I’m shallow. So, since this is my first pattern, I was going to increase the shim stack under the inner race by 0.010” in an attempt to bracket.

You're shallow, but barely. Remember, I always preach finding both shallow and deep so you know where you're boundaries are and can dial it in perfectly from there.

I think you are only maybe 2 thou off, but add a 5 thou shim and keys t see what it does. Hopefully it will indicate that you are barely deep. Then it's easy from there.

 

[Woodrow]

Added 0.005 to pinion:

Deep. Next I’ll take out 0.002-3

 

[Woodrow]

And 0.0025 back out of the pinion shim stack. I think its a runner. @hosejockey61 or @Blackjack?

 

[hosejockey61]

Just like you wrote it up! Good job. I'd run that.

 

[Blackjack]

Yep run that.

 

[Woodrow]

Update: 6 weeks and I’m still not done with this HP 30 gear set up. In post #6 above I had what looked like a runnable pattern. Then I started working on the pinion pre-load shims (no crush sleeve on an HP 30). It was my 1st time setting up pinion preload shims. Tedious but I eventually got 12-15 in.lbs. at 0.069” of pre-load stack with200 ft.lbs on the pinion nut. Great, right? Time to buy it. I pulled my new SKS set-up inner pinion race, and put in the final Timken race. But now, the pinion rotational torque is near nothing again. It took adding back edit: subtracting 0.005” from the preload stack (to 0.064”). Thats A LOT since only 0.001-2” was enough to make a big difference in rotational torque. Also, as I suspected the pattern changed. I seem to have lost or not taken a coast side pic, but the drive side looks shallower and more towards the heel.

So the SKS inner pinion set up race and final Timken race were very different. I have read you need to use new same brand bearings or races when making a setup/final pair. Now I know from first hand experience. I interpreted the above to mean the pinion was now 0.005” shallower with the final race. So I bought a Timken race to make a better matched set up race. Then I added 0.005 to the inner pinion race shim stack and back to the preload shim stack. Now, the rotational toque is still good (reassuring) and here is the current pattern. Backlash is good at 0.006”.

It seems pretty close to post #6 above to me but what do you think now? @hosejockey61 ? @Blackjack ?

 

[hosejockey61]

I'd run that path no problem.

Like my signature line says, experience is what you get just after you needed it. That sucks, but yeah, there can be a big difference between manufacturers.

 

[Woodrow]

I'd run that path no problem.

Like my signature line says, experience is what you get just after you needed it. That sucks, but yeah, there can be a big difference between manufacturers.

Thank you. I was actually thinking of your signature line as I wrote up my above post tonight. Being fairly new to this, it took me a bit to think through what was going on (the final race was making the pinion shallow compared to the set up). And then I still messed up the write up and had to edit it. This stuff is giving me a headache. But it is cool that once I figured it out, adding the calculated amount back to the inner race stack brought the pattern back. Its nice when things make sense.

 

[Rickyd]

Something I do with setup bearings and races is mic them assembled with setup and final parts to look for those discrepancies. Sometimes even then you need to take it back apart and adjust

 

[Woodrow]

Something I do with setup bearings and races is mic them assembled with setup and final parts to look for those discrepancies. Sometimes even then you need to take it back apart and adjust

Thats a great idea. I’m going to try that on the carrier bearings before I press on the finals.