Shakes

[DiscoPhoto]

Stupid D2 is still shaking over 65. Pretty much all started last fall. Drove down to Conclave at 75-90 the whole time. Wheeled the week with a squeaky drive shaft, removed that, drove to..0--blah blah blah

Anyways, drove back from ROAV -MAR to VT with no front drive shaft because it was vibrating. So I drove 85 or so smooth as shit. Got home, new driveshaft, balanced etc. Still vibrates though. Can't figure out what the issue is. Possibly ball joints on the knuckles? New panhard bushings, new radius arm bushings. 175k on the truck. Possibly front output bearing on the the t-case? Only happens when I have a front drive shaft on, but it isn't specific to any driveshaft. Want insight before tearing it apart.

 

[fishEH]

Had your tires balanced since then?

 

[DiscoPhoto]

2 different sets, same results

 

[fishEH]

2 different sets, same results

Sets of what? Tires? Is either set balanced? Maybe your new shaft is wonky. Or try pulling the rear shaft and driving...

 

[jafir]

Maybe the angles aren't right for the front shaft? You've got quite a bit of lift, right?

 

[DiscoPhoto]

Old set was balanced, new set was balanced, set on now aren't balanced. Balancing doesn't really matter, as the issue goes away when I remove the front shaft. So either pinion bearing(this diff was built last fall before the event by L8), output bearing, possibly d/shaft angle(though wouldn't make sense because I had the same lift before/after the event), or ball joints

 

[fishEH]

Old set was balanced, new set was balanced, set on now aren't balanced. Balancing doesn't really matter, as the issue goes away when I remove the front shaft. So either pinion bearing(this diff was built last fall before the event by L8), output bearing, possibly d/shaft angle(though wouldn't make sense because I had the same lift before/after the event), or ball joints

Sounds like you've got it narrowed down then! :applause:

 

[K-rover]

Is it a steering shake or a seat of your pants shake?

 

[DiscoPhoto]

both

 

[Nomar]

Do you want fries with that shake?




I would trade front driveshafts with somebody; maybe try a couple different ones and see what happens.





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[Devildog01]

Did you try taking the vibrator out of your ass?

 

[DiscoPhoto]

I've had 2 different shafts in, same results... maybe could borrow my buddy's double-double



and yes, but then the drive was less pleasurable.

 

[K-rover]

My upper and lower ball joints are pretty bad. ( original with 185,000 miles) But I can still drive 75-80 with minimal vibrations. My guess would be TC output or the diff. Driving faster than that with a lifted D2 is sketchy. Especially with no sway bars!

 

[jkempf]

Old set was balanced, new set was balanced, set on now aren't balanced. Balancing doesn't really matter, as the issue goes away when I remove the front shaft. So either pinion bearing(this diff was built last fall before the event by L8), output bearing, possibly d/shaft angle(though wouldn't make sense because I had the same lift before/after the event), or ball joints

Something has to be loose. Either a bearing or a u joint or something in the steering. These trucks are so heavy that ball joints don't cause that sort of vibration. A tie rod could but you said it goes away when you remove the front shaft so it has to be something associated with the front shaft. If you have big lift and so big angles it will amplify any play or binding in the front shaft joints. Here's a crazy idea: could the front shaft be off a spline since the rebuild? That would seriously mess up the phase of the u joints.

Where are you in Vermont? Westford?

 

[seventyfive]

I'd start by getting the truck professionally detailed inside and out then take it straight to Carmax.

 

[seventyfive]

Pull the rear shaft.

Put the front axle on jack stands. Make sure the tires are away from anything they can grab.

Have someone you trust get in the truck and give it some constant throttle while you listen to the tcase and diff with a stethoscope.

Without the driveline being in tension under load you may still be able to pick up some noise to help steer you in the right direction.

And make sure your in a position that won't get you run over if it comes off the jacks.

 

[Dane!]

Have you ever done the t-case bearing? if so, did you hit anything during the even hard enough to bend a flange?


I'd swap the bearing, my damn truck shook with a bad bearing at 50+, all because I did my motor mounts with the front shaft on...

 

[cdansan]

I have a complete spare stock front diff and housing that came out of my truck, you can try if you want to go that far. I am not sure what gear ratio you are running. Mine is lifted 4 inches with a stock front drive shaft and vibrates a bit accelerating away from a stop, no shakes at 70ish.
Let me know if you want me to try it.
Dan

 

[KyleT]

Who made the front shaft? I am having the same issue. But when I swapped shafts it went away.

 

[DiscoPhoto]

Something has to be loose. Either a bearing or a u joint or something in the steering. These trucks are so heavy that ball joints don't cause that sort of vibration. A tie rod could but you said it goes away when you remove the front shaft so it has to be something associated with the front shaft. If you have big lift and so big angles it will amplify any play or binding in the front shaft joints. Here's a crazy idea: could the front shaft be off a spline since the rebuild? That would seriously mess up the phase of the u joints.

Where are you in Vermont? Westford?

It's was a new shaft, not rebuilt. So it was balanced by the company that made it.

I'm in S. Burlington, but yes in Westford dozens of hours a week

Pull the rear shaft.

Put the front axle on jack stands. Make sure the tires are away from anything they can grab.

Have someone you trust get in the truck and give it some constant throttle while you listen to the tcase and diff with a stethoscope.

Without the driveline being in tension under load you may still be able to pick up some noise to help steer you in the right direction.

And make sure your in a position that won't get you run over if it comes off the jacks.

I'll see if I can figure out a safe way to do that... sounds like a good idea.

Have you ever done the t-case bearing? if so, did you hit anything during the even hard enough to bend a flange?


I'd swap the bearing, my damn truck shook with a bad bearing at 50+, all because I did my motor mounts with the front shaft on...

I've never done it, perhaps I should now that you say that...

I have a complete spare stock front diff and housing that came out of my truck, you can try if you want to go that far. I am not sure what gear ratio you are running. Mine is lifted 4 inches with a stock front drive shaft and vibrates a bit accelerating away from a stop, no shakes at 70ish.
Let me know if you want me to try it.
Dan

Thanks Dan, unfortunately 4.11s so that wouldn't quite jive....

Who made the front shaft? I am having the same issue. But when I swapped shafts it went away.

Driveline service of Boulder.