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"All Weeee Drive!"
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Discussion Starter · #1 · (Edited)
I know, I know, this has been covered tons.... but I've researched & tried tons...

Specs:
Waggy D44s, SOA, 2.5" BDS springs, Spool rear, Pro Comp 35s.

I've been in rigs with Death Wobble, but this is way worse. Once I hit 38 mph my rig bucks like a bronco. The tcase bangs on the frame rail (about 1" over). Front wheels flail 6" either direction and don't stop until I get below 5mph.

The drag link, TREs & ball joints have about 3k miles on them (including 12 trail rides) with this set up.
Without any DW before.

I swapped in new springs before last trip (not sure if it had death wobble with them).
I added a rear anti-wrap bar at that time too.
On the trip I tore a rear sidewall, so I swapped on a BFG used, but almost new spare.

DW started after I returned from that run (I trailered the rig on the trip).

I've replaced the tranny mount (it was shot).
Changed the tires.
Tightened all bolts (springs, u-bolts, etc. etc.)
Swapped in another Driveshaft (pretty sure it's balanced... it's new jeep old stock).
Tire pressure is at 35psi.

I just measured the toe in/out & got 50" on the front & 51" on the back of the tire... (it's hard because the springs & DS are in the way)...
I'm guessing it's more like 50.5" in the back.

At this point, I'm ready to try & swap in another Tranny mount (on the off chance the new one was bad to begin with).

Other things to try are lowering the tires to 28psi and also remove the anti-wrap bar.

New ball joints.

Any other suggestions?
 

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Change is good.
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35,184 Posts
Hydro assist did it for me. I know it's a bandaid, but I needed the HA anyway.
 

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I know you said you checked all nuts and bolts to make sure they are tight. Make sure the ball joints (mainly uppers) are tight. Also, check to see if steering box is still tight to the frame. Also check to see if the tre's are still ok and tight. Other than that, check all the bolts again. I would suspect something isn't as tight as it looks. Good luck, DW sucks.
 

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5,750 Posts
death wobble starts in two areas---- miss matched tires- and tires out of balance--

other things will add to it- but it starts with tires and grows from there--
 

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bent wheel? Wheel not right for axle? Wheel not tight? Just some ideas.
 

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"All Weeee Drive!"
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12,032 Posts
Discussion Starter · #7 ·
After I posted this I jacked the front up to check the ball joints.
They seem tight... The wheels rock like 1/16" back & forth.
Might be the bearing nut isn't tight enough, but I doubt it.
I was able to tighten 3 of 4 PS bolts just about I full rotation.

That helped, in fact that along with 28psi made the 1st test drive work (hit 45-50mph without DW).

I then tuned my carb & went for #2 & it came back.:(

When I said I changed the tires, here is what I did:
I was running a BFG spare on the left rear.
I got a 2nd BFG mounted & balanced yesterday, so I swapped it in place of the other BFG just in case. That didn't work.
So I swapped the 1st BFG to the right rear. That didn't work either.

Maybe it's one of the fron Pro-Comps..
I might try swapping those later...
 

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Jack it up and put it on 4 jack stands...

Lock it in 4wd and spin it up and see whats shakin'.....

Tow in should be 1/8" toe-in with big tires... (Thats what I set 'em to anyways)


How much slop is in the steering BTW?


Chris:cool2:
 

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"All Weeee Drive!"
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12,032 Posts
Discussion Starter · #10 ·
Jack it up and put it on 4 jack stands...

Lock it in 4wd and spin it up and see whats shakin'.....

Tow in should be 1/8" toe-in with big tires... (Thats what I set 'em to anyways)


How much slop is in the steering BTW?
I'll try that if I have time before we leave today.

Steering is pretty tight.

I just checked all the steering nuts: ball joints, TRs & DL.
One TR tightening nut was loose, but the TR was itself was tight.

One thing I didn't mention was that when I put the new springs on (same as old ones) I moved the front hangers forward 3-4 inches.
Now the drag link at the Pitman arm is slightly behind the TRE.
 

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Gravity Works!
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30,943 Posts
Fawkin DW:shaking:

I swapped my shackles up front (Toyota) like the Scout's and Heep's. At the same time I installed D60 and 40" TSL's - was a Toy straight axle and 36" tsl sx's. DW was really bad, I welded braces in between the front shackle links to brace them - helped some. Got back from the maiden voyage and just installed 42" TSL's - replaced the shackle grommets (were loose) and installed a pan hard bar from frame to top of diff. This helped a ton but the asswhipe DW is still there.

I'm installing full hydro after this weekend so that should do it for now. I'm not crazy about the pan hard w/leafs.
 

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Gravity Works!
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I'll second on the caster. Check factory spec and try to get it in the ball park. Also check camber on those waggy axles. I added shims to mne when I actually drove it on the road.
I'm going to say this is most of my problem. I installed the shackles up front to get the pinion angle I needed but it's a touch too much. I'm not going to rotate my knuckles yet as I have other plans for a rig next year and I'm not sure how all that's going to lay out just yet. I'd rather rotate them once.

But I bet this is his problem moving things around and all.
 

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Jack it up and put it on 4 jack stands...

Lock it in 4wd and spin it up and see whats shakin'.....
I'm sorry but I can see this going so wrong so quick :laughing: :flipoff2:

Deathwobble is such a PITA. Mine ended up being tires out of balance and the suspension being loaded to 1 side.

I'd also ask how much slop is in the steering?
 

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"All Weeee Drive!"
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12,032 Posts
Discussion Starter · #15 ·
Caster is good... Camber might be off (having uneven wear).

I've put 3k miles on these axles (500 flat towing) without any hint of DW prior to me moving the springs forward a bit, or this wheeling trip.

No time to solve it before this weekend, fortunately I'm towing it to the Trailhead....
 

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Comment # 4 for castor angle! What is yours at?

I have a big military truck that does it with the tires at 40 psi. everthing is big strong and stiff on this truck but when DW starts it all turnes to jelly. With the tires at 50 psi it doesn't do it at all!!

'43 chevy 1 1/2 ton:

 

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Camber might be off (having uneven wear).
probably due to to much toe in.

my dw was too much caster and i put in a panhard. caster was at 10 now at 6, panhard has bushings on both ends, and (no stabalizer ) . i have no more dw.

whats your bs on you wheels? maybe to much scrub radius!

good luck!!!!!
 

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"All Weeee Drive!"
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12,032 Posts
Discussion Starter · #20 · (Edited)
Caster is at 6*...
It was at 2-3* for the first 500 miles, it's been at 6* for the last 2500.

I've never had it during the previous 3k miles, so I doubt it's caster.
Possibly toe in... I'll adjust that next week, as well as swap front tires.

EDIT: BS on wheels is 4". Same as it's been for 3k miles.
 
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