something....bent?

[goodtimes]

Hey all....after a *difficult* trail run today, I picked up a new.....uh....shake. It feels like the beginning of death wobble...as in: The first second or two of death wobble when you get that low frequency vibration come up the steering column and the wheel starts shaking back and forth....just before it becomes violent....if you've ever had death wobble you know the feeling.....the deal is though...I don't pick this up at 35mph like I typically do with death wobble.....it only happens from about 50 mph to about 55 mph, and it never gets violent like death wobble does. The steering wheel shakes like it is going to get worse, then it just stops. It doesn't matter if I am accelerating or decellerating or coasting...brake pedal pushed or not......

anyone ever have this problem (and please don't tell me you had it when you bent the flange on a rear axle shaft......'cause that wouldn't surprize me after falling off that last water fall today....)

[Dukes69]

I have the same thing. I'm pretty sure one of my rear shafts might be bent a little. Or maybe a tire spun on the rim causing it to become out of balance. Thats all I can add.

[tjrubicon]

That sounds close to what I have going on, but mines any where from 45 - 55 then stops or doesn't do it at all. Mines been doing this for about the last 2.5 months and I haven't been able to beat it on the trails since June so I have no idea. If you figure it out, update us so I'll have a starting point Its a pain fighting a shake and driving on ice.

[blackZZR]

I like to get under my jeep and put my hand on everything after each trip offroad, that way I check out all carnage done and decide if it is bad enuff for a patch or if a new part is needed. But I am kinda anal that way. I would suggest getting under there and looking around as it may be faster than chasing down every suggestion you are going get from every forum you post on. But the advice of what to look for is excellent also.

[blkTJ]

I like to get under my jeep and put my hand on everything after each trip offroad, that way I check out all carnage done and decide if it is bad enuff for a patch or if a new part is needed. But I am kinda anal that way. I would suggest getting under there and looking around as it may be faster than chasing down every suggestion you are going get from every forum you post on. But the advice of what to look for is excellent also.

can you see a bent flange??? :dunno:

[goodtimes]

I've already done the post-trail/pre-drive home inspection of the drivetrain, suspension and steering. It isn't that simple....

[tjrubicon]

Same here..I've retorqued, checked bushings, checked everything I could think of, then checked torque and everything else again and again. My toes way off again, but thats simple and takes a few minutes to correct. Hence the reason I'm lost on whats causing this to happen to me also.

[blkTJ]

don't disregard balance. tire or driveshaft.

[goodtimes]

I have had a vibration ever since I put the lift on.....what I am feeling now is definately a *different* problem. I have been unable to get the tires balanced (ever!). I have literally taken them to one shop (Discount...AKA American for you socal people), had them balanced...left the shop, driven 8 or 9 miles to another discount tire, had the balance checked, only to find they were all out in excess of .50 oz/in. Every time they are checked, they are out of balance. I have given up trying to get these tires balanced. (BTW Brian, you probably don't want to see what they look like....)

The driveshaft (rear) has been checked, and is good (or so I am told), pinion angle has gone everywhere from 0.5* to 3.0*, with it picking up a vibration between 2.5 and 3.0*. Pinion angle is now at 1*, as per Tom Woods recommendation when I first installed the lift and was trying to find the vibration (BTW---Tom Woods is a great guy to work with. He spent quite a bit of time on the phone with me trying to figure out what is going on). I have never had the front checked...suppose I should pull it out and see what happens.

I did pull the RR axle shaft tonight. Anyone have any idea what the tolerance for axial runout on the flange is? (that would be measuring the face of the flange where the wheel mounts). Using my ultra-high precision axle flange measuring jig (piece of c-channel with a pair of v-blocks and a dial indicator), I am measuring .00144" runout per inch of radius. With the ~32" tall tire, this equates to about .023" runout. That is higher than I expected, but I don't think it is enough to cause anything as severe as I am feeling....thoughts?

[blkTJ]

I've bent both rear flanges, driver and passenger. neither were noticable from drive characteristics. both were diagnosed from visual, driver from me, passenger from erik driving behind me. I doubt this is your problem.

remove the front driveshaft.

report.

[tjrubicon]

I was going to pull my front drive shaft when it first started doing this. I never did because I can't get to the bolts at the tcase. Of course the only 8mm wrench I have is a shorty and I couldn't get my 1/4" ratchet in there. If you get the drive shaft out, can you give me a tip on doing so? I think the majority of my problem is the u-joints (things had "angry sparrows for quite a while now). That and my tires, they haven't been balanced again since I have had them......about 35k miles ago.

[blkTJ]

I've always just used an 8mm wrench. yes, it's a pain in the arse.

[goodtimes]

I've always just used an 8mm wrench. yes, it's a pain in the arse.

Damn, you aren't kidding! I hope I never have to pull another one again! (OK, it wasn't THAT bad...but it wasn't fun).

So.....the front driveshaft doesn't affect the goofy low frequency vibration I pick up between 50 and 60mph....but it did seem to take care of the higher frequency vibration I have from 70mph+ (kind of a rough road so there may still be some vibration there...but it isn't as bad as before)....so, I need front driveshaft work &/or front pinion angle adjustment.....but, I still have this other issue......steering looks good....other than I'm trying to figure out how the HELL I bent the currie tie rod (without hitting it on a rock...as there is no rock rash in the area of the bend).

Another post-alighment road test in a bit....