Front drive shaft vibration after re-gear

S

Sh4rkattk

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Joined
May 9, 2019
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31
Location
Los Angeles
Hi all

Got a front ds vibrating like crazy on me. Starts at 65 and gets much worse. All started after a regear. 4.10 - 5.38

Everything on the front axle is pretty much new. Unit bearings, axle shafts, bbk which include knuckles.

Things I have done to try to remedy.

1. Remove front ds and vibes go away. Drives smooth as butter at any speed to limiter.
2. Replace ds with a Tom woods.
3. Taken tw ds to a local ds builder. Balanced to 3500rpm. Which is approx 67 mph if it were on the rig.
4. Pinion angle is set to 0
5. Checked output yoke on tcase if loose.


I'm at a loss what to do. All I can think of to do next is replace the pinion yoke.
 
I've adjusted the pinion from up down +-3 degrees in .5 degree increments. 0 to 2 down was the best and still not gone.

To check the output yoke. I assume remove front ds put it in 4wd with the rear in the air and let it run?
 
Could be gear related since you just had it done. The lpd30 uses a crush sleeve to set pinion depth, can be a pain in the ass to get it right.
 
Try pulling front ds and both front tires. Try to rotate the axle by hand at both sides (pull brake pads too) and at the pinion. Do you feel any grinding? Binding? Catching? Etc. Everything should be smooth. Check the fluid level too. You never know.
Try rotating tires front to back. Every Jeep is different. What should shake a suspension apart on one TJ may be what smooths it all out on a different TJ.
 
Uh oh... if it didn't happen until after the re-gear, you may be facing the dreaded re-gear vibration that a lot of us (myself included) have faced. @toximus solved it with a manual hub conversion on the front. @psrivats solved the bulk of it by taking it to a speciality drive shop (but lost his mind in the process, as well as thousands of dollars).
 
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Chris said:
Uh oh... if it didn't happen until after the re-gear, you may be facing the dreaded re-gear vibration that a lot of us (myself included) have faced. @toximus solved it with a manual hub conversion on the front. @psrivats solved the bulk of it by taking it to a speciality drive shop (but lost his mind in the process, as well as thousands of dollars).
Click to expand...

Any manual hubs that work with the BMB BBK?
 
Try lowering the t-case skid. Go 0.25" at a time with washers. I was able to dial most of mine out at 0.75" of drop, so ended up putting a 1mml on and then put the t-case skid back up where it belongs.
 
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bobthetj03 said:
Try lowering the t-case skid. Go 0.25" at a time with washers. I was able to dial most of mine out at 0.75" of drop, so ended up putting a 1mml on and then put the t-case skid back up where it belongs.
Click to expand...
This^ For starters. It’s free and easy to do.
 
bobthetj03 said:
Try lowering the t-case skid. Go 0.25" at a time with washers. I was able to dial most of mine out at 0.75" of drop, so ended up putting a 1mml on and then put the t-case skid back up where it belongs.
Click to expand...

I don't really want to drop the tcase want as much clearance as possible.
 
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