Death wobble - 4th gen linkage upgrade

[Dr. D]

Recently experienced the notorious death wobble in my truck. It was a pretty interesting situation.

I had a 200lb rock in the middle of the bed, supported by 4 60lb sand bags. I hit a bump in the road going just the right speed (50mph ish), and it came. My mom in the passenger seat about had a heart attack, and I hung my head because I knew exactly what it was, and the BS I'd have to deal with. Then, last night it happened at 75mph when I hit a short bridge on the 680 in Walnut Creek, CA.

Upon about an hour of homework, I came across a pretty old thread about a guy that did a "3rd gen upgrade" using a 2010 system - on his 2001.

https://www.dieselbombers.com/5-9l-24v-performance/59210-bomb-proof-bolt-2nd-gen-steering-cheap.html

I got stoked, cause it was a whole assembly, and I didnt have to press ball joints. And, its pretty damn cheap.

The part number he used: Mopar # 52122362AF

This is an outdated number that has been changed to ...AI at the end, I believe. Anywho, I found a Moog replacement for slightly less than Mopar. This number is Moog # DS800981A. I believe I bought it for the 2010 model year when I ordered it off of Atech auto.

No, the Moog doesn't have greaseable joints. It sucks, but I am a college student that aint got money for an $800 steering linkage system.

These posts have kind of gotten beat to death, but in case anyone is interested, I'll take some pictures when I get the parts in a day or two.

Also, my truck is leveled with the lame blocks (they'll be going soon), and riding on 285/75/r17's. If this doesnt fix my wobble, I am going to be pissed to replace my u-joints. My steering is pretty sloppy as of now, and is probably about time for some front end stuff.

If anyone here has some experience and pointers to make this go as efficiently as possible, any advice would be greatly appreciated.

Luke

 

[Dr. D]

I also have a steering box brace, if anyone wanted to know.

 

[BarryG]

I did the upgrade on my 01. It went smooth as silk. Two things come to mind. First the steering stabilizer will need to be replaced as well since it is a different type mount. Secondly I had to grind down the pass side tie rod bolt as it scraped the inside of my wheel when turning. There was plenty of bolt so was not a problem at all

 

[GrantP]

Not trying to be a jerk, but have you done any diagnosis on the front end to find what's loose or are you just throwing parts at it? Triple check the track bar. The steering box brace as you've discovered isn't a solution, nor would a new steering stabilizer be. Don't see how U-joints would play into this either.

Find what's loose and fix it.

 

[Dr. D]

Barry, I will be replacing the stabilizer with an aftermarket piece, likely with a brace that uses U-bolts that clamp on the axle just passenger side of the pumpkin. Unless I can rig a piece from the adjusters on the current linkage. Also, from what I understand, since I've got 17's (that are also a bit offset) I shouldnt struggle with tie rod bolt contact on my passenger wheel... in theory.

Grant youre not being a jerk. Ive been busy, I did jack the truck up and fins some pretty weak ball joints. Youre right, panhard rod could be the culprit over U-joints as U-jionts really dont give play laterally. I'm just hoping the issue isn't some trigonometrical issue I cant solve via trouble shooting. I suppose I could have some worn control arm bushings as well, and I'm also hoping that isn't giving me the wobble

Thanks gentlemen for your advice, feel free to keep it coming. Everything helps.

Luke

Update: If anyone is wondering, I also just got bad wobble on the freeway at 75mph unloaded after hitting no bump. I really shouldnt be driving this rig anywhere.

 

[JR]

Sounds like you've got a good start. Control arm bushings are a definite possibility as well.
What brand are your tires? What psi do you run in the front?

 

[SnoKing]

Recently experienced the notorious death wobble in my truck. It was a pretty interesting situation.

I had a 200lb rock in the middle of the bed, supported by 4 60lb sand bags. I hit a bump in the road going just the right speed (50mph ish), and it came. My mom in the passenger seat about had a heart attack, and I hung my head because I knew exactly what it was, and the BS I'd have to deal with. Then, last night it happened at 75mph when I hit a short bridge on the 680 in Walnut Creek, CA.

Upon about an hour of homework, I came across a pretty old thread about a guy that did a "3rd gen upgrade" using a 2010 system - on his 2001.

https://www.dieselbombers.com/5-9l-24v-performance/59210-bomb-proof-bolt-2nd-gen-steering-cheap.html

I got stoked, cause it was a whole assembly, and I didnt have to press ball joints. And, its pretty damn cheap.

The part number he used: Mopar # 52122362AF

This is an outdated number that has been changed to ...AI at the end, I believe. Anywho, I found a Moog replacement for slightly less than Mopar. This number is Moog # DS800981A. I believe I bought it for the 2010 model year when I ordered it off of Atech auto.

No, the Moog doesn't have greaseable joints. It sucks, but I am a college student that aint got money for an $800 steering linkage system.

These posts have kind of gotten beat to death, but in case anyone is interested, I'll take some pictures when I get the parts in a day or two.

Also, my truck is leveled with the lame blocks (they'll be going soon), and riding on 285/75/r17's. If this doesnt fix my wobble, I am going to be ****ed to replace my u-joints. My steering is pretty sloppy as of now, and is probably about time for some front end stuff.

If anyone here has some experience and pointers to make this go as efficiently as possible, any advice would be greatly appreciated.

Luke

Crank in more caster. That is lengthen the lower control arms.

 

[Dr. D]

Ive got some 10 ply Toyo A/T's (load range E) I keep aired up. I believe its about 60psi when warm... I could be off. Before the wobble the truck didnt shake at all, I'm suspecting theyre still in good order and balance. However just to be sure, after the linkage replacement I plan to get a balance when I get the girl aligned professionally.

 

[GrantP]

Completely agree with adding more caster...after the OP has a chance to find out if there's anything loose first.

 

[Dr. D]

That’s a good idea. However I’m not sure how to add more castor without using correction bushings or brackets. Or perhaps a control arm drop piece.

I had an FZJ80 I had to use brackets to correct castor on a lift.

As soon as I have access to a lift tomorrow I’ll be able to ID exactly what’s giving me hell.

Thanks for all the ideas gents. Again, keep them coming.

Luke

 

[GrantP]

That’s a good idea. However I’m not sure how to add more castor without using correction bushings or brackets. Or perhaps a control arm drop piece.

I had an FZJ80 I had to use brackets to correct castor on a lift.

As soon as I have access to a lift tomorrow I’ll be able to ID exactly what’s giving me hell.

Thanks for all the ideas gents. Again, keep them coming.

Luke

Just crank the cams at the axle end of the lower control arm.

 

[Dr. D]

Took a look at the caster bushings. I see that they're not clocked at the same angle, but my very basic knowledge of caster tells me thats not necessarily a bad thing. Driver side is about 2:00 towards front, (about 40*) while passenger is about the same 2:00 (40*) towards the rear.

driver side

To increase road stability, I would need to decrease caster angle (rotate axle backwards), correct?

As soon as I test drive the new linkage, should it still show some hints at wobble, I'll decrease caster angle.

Again, much appreciated.

Luke

 

[BarryG]

DR D
Go to the 4wd alignment section in the link below the specs worked for me for 17 years and never had a wobble, also check Brent's discussion for proper way to use the eccentrics sounds like yours are not set right
http://dodgeram.org/tech/specs/00_steer_specs.html

 

[SnoKing]

Took a look at the caster bushings. I see that they're not clocked at the same angle, but my very basic knowledge of caster tells me thats not necessarily a bad thing. Driver side is about 2:00 towards front, (about 40*) while passenger is about the same 2:00 (40*) towards the rear.

driver side
View attachment 107217 View attachment 107218

To increase road stability, I would need to decrease caster angle (rotate axle backwards), correct?

As soon as I test drive the new linkage, should it still show some hints at wobble, I'll decrease caster angle.

Again, much appreciated.

Luke

https://groups.google.com/forum/#!msg/alt.autos.dodge.trucks/p3UOqjcXbJE/79CJ530kj_oJ

 

[Dr. D]

That is exactly the information I need. Thanks for the links.

Linkage still ain't here yet. Getting excited to put it on.

 

[Dr. D]

Got the linkage in with no problem. As expected, the old linkage wasn't happy to come out, but from there, it was smooth sailing.

Things to note: The steering stabilizer bolted right up. It has plenty of life still in it, so I'm keeping it.

Also, About 1/2" had to be removed from the tie rod in the adjuster in order to get the steering wheel straight.

After aligned, the truck drove pretty straight, but not as tight as I had hoped. This was pretty disappointing, but it hasn't wobbled yet.

I climbed under the truck and had a friend jerk the wheel around. I thought I saw the panhard rod moving slightly, however, he did not and said that the two beers really got to me.

I am anticipating a new panhard rod in the near future.

Thanks for all the help gents,

Luke