had a bad experence with the "death wobble" and fixed it with some new bushings. just got some swampers on and what do you know its back for vengence. bushings didnt look to healthy so i canged those up again and its still pretty bad. tommorow im going to put them on the wheels there going to stay on and get them balanced. any other ideas on what to check? i dont think the balance can affect it only going 30mph. i need to check my alignment tommorow too.

 

So did you take her fr a test spin after we finished replacing those bushings? Did it fix the wobble?
-=Morphine=-

 

Check for looseness at the transfer case rear out-put, or pinion, flanges. Tighten the t-case flange, if loose, pinion flange will need properly torqued. Mine needed a new flange, due to run-out, which was the last thing on a long list. Check the u-joints, too. See if your rims aren't seated flat against the brake drum, scrape the crud off the surfaces where they meet and the inside of the drum where it contacts the axle shaft hub, and the hub face.

 

yea morphine it still does it. haha man i was so mad after we fought with those stupid shackles to get em out haha. tommorow im going to have my new wheels put on and have them balanced so we'll see if that helps. and mud hippy it sounds like your talking about the rear tires its the fronts that are shaking really bad

 

Well, I shoulda watched part 1, oopsy.

 

check your u bolts,wheel bearings, steering

 

I found in my case, caster angle was the key to curing DW. I had too little caster and adding about 1.5 degrees totally eliminated it.

Also, try and figure out why the bushings are wearing out so fast. I typically get several years out of a set of front bushings on my '85. Typical sources of wear are shackle side plates that don't sit flush to the bushings or ones where the bolt holes have been worn too large:
http://www.4crawler.com/4x4/ForSale/...l#Introduction

 

after the new wheels and balance the death wobble is still there. the bushing wore out fast i think becuase i may have overtightned the bolts 4crawler you talk about caster angle, sorry to sound stupid but what is it your talking about? alignment? checked it today and it was dead on. 54.5 inches and 54.5 inches. are you saying to go toe in a little?
its very possible that the swampers i put on are just too nobby and cause too much vibration. maybe it could be stabalized with a dual steering stabalizer set up and boxed in shackles? idk. i need some help its getting frustrating.

 

Caster is the angle your axle is "clocked" at compared to the ground (you can also think of it as the angle between your t-case output and your pinion flange in some cases). You can change it by putting shims between your leaf spring and perch.

I'm not sure of the best way to measure caster, or what the optimum angle for your truck is, but I know that too small a caster will lead to an unstable condition in the steering and cause the infamous "death wobble" when braking, or even while coasting.

 

Yep, caster angle is part of the alignment, along with toe (camber as well but not easily adjustable on a solid front axle). Stock caster angle specs below:
- http://www.4crawler.com/4x4/ForSale/Shims.shtml#FAQ1

Bias ply Swampers are the pits on the road, I ran 33x15.50 SX's for many years. But that said, once I had the front end set up right, I could run those meats w/o a steering stabilizer. With it set up wrong, new bushings and steering stabilizer and it would still wobble.

 

gotcha. so next step in the death wobble conspiracy is getting some axle shims for my front axle?

 

Thats one thing I dont miss about having my solid axle jeep. I was running mediocre tires on it and then switched to some very good tires and never had a problem with it again just to let ya know.

 

Well, next step would be to find out what your caster angle is now and figure out if it is a problem and if so what angle do you want to end up at to fix it. Then you can get shims made to match that angle difference.

 

other than going to an alignment shop to get a print out of my caster angle how would i measure it myself?

 

Yes at 30mph it can wobble(If rims aren't balanced or the stock stablizer shock is bad because on My 89 4Runner it wobbled with 35's@ 30-35mph.I had the rims balanced & put on a PRO COMP stablizer an it went away. so look into that too

 

Read the web page I posted a link to earlier. Some tips there.

 

just got new wheels and everythings balanced and the steering stabalizer is new from the marlin hy-steer kit put on no more than 6 months ago i want to say

 

does a bad angle in either direction cause death wobble?

 

Makes no difference if everything is new, if things are not set up right, it is going to wobble no matter what. Ever push a shopping cart real fast, look at the front wheels, that is wobble due to (bad) caster angle. In fact that is all it can be due to as those wheels are straight up and down (so no camber) and are not tied to each other (so no toe-in or -out).

Too little caster angle (just like the casters on the front of the shopping cart) makes the tires wobble. And too much can do the same thing. THe whole deal with caster angle is where the steering axis intersects the tire's contact patch. Follow the king pin angle down to the ground and see where that hits vs. the tread print. Ideally you want that point in front of the center of the contact patch. That way if wobble starts (e.g. hitting a pot hole), the tire's contact patch scrubbing behind the steering point damps out the wobble (like dragging your feet to stop on a skateboard). Move the steering axis too far forward can mess things up as well. There is usually a few degrees window to work in, maybe from 2 up to around 6 degrees (stock is 1.75 degrees).

When I started having problems, I was probably at or just a little below stock caster. Used to be fine when I ran only a 2" longer front spring shackle w/ stock front hanger. But when I dropped the front hanger 2.5", I tipped the axle back, killing my caster angle, hello wobble! Later added 1.5" to my rear shackle length and wobble vanished. 1.5" of shackle is about 1.5 degrees more caster angle. So I probably went from like 3 degrees to 1 degree to 2.5 degrees and when it was 1, I had wobble, when it was more than 2, I did not.

 

You also need to check front wheel bearings and your knuckle bearings.

Pull your wheels and tie rod. Rotate your knuckles by hand (do both sides). They should move freely with some drag, and should not be 'knotchy' or have any sticky spots in their rotation. If they do, it's time for new knuckle bearings.

Regrease and torque your wheel bearing as well.

With wheels balanced and the right shims, and wheel and knuckle bearings set right, the truck should track straight and smooth to 80 mph, WITHOUT a steering stabilizer.

Lots of guys are putting on stabilizers and it masks a bad setup or bad maintenance. Get it setup right, then put the stab on.