[leesmoneypit]

I have a 98 xj and have a death wooble @ 55-60mph and being a tire tech years ago i know tire balanace has a effect on this but its getting to the point where it doesnt matter and im sure no front work has been done so ready to spend $300 for pst front end kit which includes everthing but what causes this besides worn parts and tire balance? One more thing the seats keep breaking, im on my 3rd set so should i put some extra welds on my next set? I love this jeep she has 220k on her and can still beat up 4.6 auto mustangs and oil pressure has fallin though the years but nothing to worry about.Any help on my front end and seats?

 

[MRGTX]

I have a 98 xj and have a death wooble @ 55-60mph and being a tire tech years ago i know tire balanace has a effect on this but its getting to the point where it doesnt matter and im sure no front work has been done so ready to spend $300 for pst front end kit which includes everthing but what causes this besides worn parts and tire balance? One more thing the seats keep breaking, im on my 3rd set so should i put some extra welds on my next set? I love this jeep she has 220k on her and can still beat up 4.6 auto mustangs and oil pressure has fallin though the years but nothing to worry about.Any help on my front end and seats?

Lee,
How did you make out?
You're right on about the tire balance being a factor but in the end, the kit is the only solution from what I have read.

Mine is still pretty solid at 155,000 but I'm always keeping an eye out on how others are keeping their Jeeps on the road and tracking straight.

 

[Mekanic]

Death wobble is a harmonic resonance in the front steering parts. (that is EVERYTHING that moves when the wheels turn)
And any slop in any of these parts makes the resonance happen easier.
Now there are a few more parts that are NOT supposed to move when steering that can cause it or make it worse.
First make sure all steering parts have no slop in the waer points. AND then make sure the steering box is tight on the "Frame" and doesn't move.
Then you have the trac bar bracket on the "Frame" then you have to check both ends of the trac bar and it bolt on the axle end and bushing i=on the axle end.
then you have to check all 4 ball joints, tie rods, wheel bearing units,

ALL steering parts(including ball joints and wheel bears ) can be new & fine and if the trac bar lets the whole axle move left and rightyou will get death wobble.

 

[MoparNorm]

Wow, now did I miss this thread?
Not in any order, the causes of front end shimmy are: ( the term death wobble is so overblown with hysteria)
Alignment (toe, caster)
Balance (dynamic of both wheel and tire)
Ball joints
Steering component ends
Steering box (both play at mounting and sector shaft wear)
Bent wheel
Worn Shocks & Stabilizer*



* Dont rely upon a steering stabilizer to fix shimmy, it's a band aide, not a cure.

 

[mowgod]

Like every one has said make sure the front end is tight even the control arm bushings will cause this if all is good then change the steering stabilizer and use a good one as a tech in the busness i only will use the moog or rancho stuff as it lasts a little longer the ones from monroe fail very quickly and i have had to change a lot of them out

 

[MoparNorm]

Like every one has said make sure the front end is tight even the control arm bushings will cause this if all is good then change the steering stabilizer and use a good one as a tech in the busness i only will use the moog or rancho stuff as it lasts a little longer the ones from monroe fail very quickly and i have had to change a lot of them out

Rancho is Monroe, with a different box. Again, the stabilizer is a band aide, not the cure, better quality stabilizers are FOX, Bilstein, OME. But regardless of brand, it won't fix the shimmy, only mask it.

 

[mowgod]

make darn sure that the track bar is good how i check them is have someone rock the steering wheel back and forth slowly with the engine running and all four wheels on the ground there should be little to no movement side to side with the miles you say it has the track bar is probely your problem spring for the good parts though cause the cheep ones just go bad fast

 

[Cornupenuria]

I thought Xjs had king pins or king bolts instead of ball joints. Did I miss something?

 

[MoparNorm]

I thought Xjs had king pins or king bolts instead of ball joints. Did I miss something?

There are ball joints in steering arms, track bars, etc AND the joints at the knuckles are technically ball joints as well.

 

[Cornupenuria]

There are ball joints in steering arms, track bars, etc AND the joints at the knuckles are technically ball joints as well.

Norm, you're right. I just know all of those parts by other names and inferred that the author of the first list of suspect parts didn't know the XJ had king pins.

 

[MoparNorm]

Norm, you're right. I just know all of those parts by other names and inferred that the author of the first list of suspect parts didn't know the XJ had king pins.

Along those lines, Dyna-Trac makes a great, rebuildable upper and lower steerin knuckle ball joints. They are pricey, but bullet-proof!

 

[floridaman2013]

When I was in the business as a tech, I changed numerous track bars that were shot around 60,000 miles. guess it depends on the type of roads driven also.

 

[Cornupenuria]

I had a solid-front-axle motor home on which none of the above solved the problem. After trying them all in least-to-most-expensive order we finally added a leaf to each front spring then re-arched the springs. The shimmy didn't recur during the rest of the time we owned the motor home. So if all else fails, try replacing sagging front springs.

The spring shop service manager said he had seen that problem more often on motor homes, and with fewer miles than on other trucks. His theory was that when the chassis were shipped by rail from the truck factory to the motor home factory they were sometimes cinched down too tightly on the railroad flat car and the loss of spring arch didn't get out of specs until a few years after the assembled motor home had been on its wheels. I know too that the motor homes had lower spring rates than farm trucks and utility company trucks with the same front axle. I realize this doesn't all pertain to the XJ but it does pertain to shimmy problems on other vehicles.

 

[MoparNorm]

I had a solid-front-axle motor home on which none of the above solved the problem. After trying them all in least-to-most-expensive order we finally added a leaf to each front spring then re-arched the springs. The shimmy didn't recur during the rest of the time we owned the motor home. So if all else fails, try replacing sagging front springs.

The spring shop service manager said he had seen that problem more often on motor homes, and with fewer miles than on other trucks. His theory was that when the chassis were shipped by rail from the truck factory to the motor home factory they were sometimes cinched down too tightly on the railroad flat car and the loss of spring arch didn't get out of specs until a few years after the assembled motor home had been on its wheels. I know too that the motor homes had lower spring rates than farm trucks and utility company trucks with the same front axle. I realize this doesn't all pertain to the XJ but it does pertain to shimmy problems on other vehicles.

I could almost guarantee you that the spring bushings, or connections were loose or worn and changing the springs included changing those components , which solved the problem. Spring rate is rarely the cause, but spring connections frequently are.

 

[Cornupenuria]

I could almost guarantee you that the spring bushings, or connections were loose or worn and changing the springs included changing those components , which solved the problem. Spring rate is rarely the cause, but spring connections frequently are.

That might well be true. We had had it worked on at both a Dodge Truck dealer [class 3 - class 7 or 8; back when Dodge still made those] and a tire store that serviced class 3 - class 7 trucks. We had gotten the shimmy down to where it rarely occurred and was mild, but still annoying.

We finally had the front springs re-arched and a leaf added to each because they had sagged so much that the caster couldn't be brought into specs with the thickest wedge in the kit. The shimmy didn't return the rest of the time we owned the motor home, maybe 15,000 miles. The ride wasn't rough with the rebuilt springs. We did have to re-aim the headlights.

I had always suspected the Saginaw power steering unit was part of the problem.