>>Plot THICKENS: "DEATH WOBBLE" afflicting my 4x4 (Torsion Bars) Ranger--missing PVH hubs allow half-shafts to flop around!!

[fixizin]

Symptom: when hitting a "sharp" bump at speeds over 40 MPH, (feels like) right front wheel starts VIBRATING the whole truck to the point that image in rear view mirror is blurred... LOUD wheel-RPM-dependent moan/buzz as if tire is shredding itself. Have to slow to 10 MPH to make it stop/disengage... all good at any speed until next manhole/pothole/railroad track is hit. It's like the splines are partially/fully engaging, but there's a dried out CV joint or...??

Tires are new, < 1,000 miles, brakes, ball joints and alignment fine. With previous softer/worn tires, only happened rarely, and only at speeds over 60 MPH... lately happening ALL the time, at speeds down to 35-40...

Though 1999, only 76k total miles. 2 years/10,000 miles ago, front sealed bearings went, had family owned tire shop replace them, they handed me the crappy plastic PVH hubs and said "these were just laying loose in the hub covers, not doing anything, so we left them off..." and indeed the 4WD hasn't worked for 8 years for other reasons (vacuum lines, shift motor, etc.)... and for many months truck seemed fine in 2WD without them...

 

[Uncle Gump]

I've seen the cheap replacement wheel bearings fail with 10k on them.

I would ensure the lugs are properly torqued first of all. I would also rotate tires if you feel it coming from a particular spot and see if the vibration moves with it. If it does... could be a balance issue or even a bad tire.

Did you have it aligned? Inspect the ball joints?

 

[alwaysFlOoReD]

My first guess is also wheel bearings. Make sure they are torqued to the correct spec.

 

[RonD]

New tires...............what about the wheels?

Yes, I would rotate front to back

Can't see CV causing it, not enough mass
Would have to be tire, wheel or hub, IMO

Maybe the shock but that would be a long shot, but not a no shot, it should prevent repeated bouncing of spring on that wheel

 

[fixizin]

Mentioned it to a Jeep buddy at lunch, and he knew EXACTLY what it was, including the way it cleanly "resets" once you slow below a threshold speed, it's... The (infamous) Ford/Jeep "Death" Wobble! There was even a huge CLASS ACTION LAWSUIT against FoMoCo pertaining to F-250 & F-350 4x4s... ( I CHANGED THE THREAD TITLE )

While the above insights and suggestions are good ones, it turns out this not caused by a single wheel/tire/bearing, but (most often) by an interplay between the left and right wheels via sloppy tie-rod(?) bushings... so while it's NOT grinding the splines off of my half-shafts (that's what it SOUNDS like), it IS scrubbing the shyte out of my new Firestones (when it triggers).

Will have it in to the front-end shop on Wed. 12/18, and report back... very sad to think my bushings are shot, after "only" 20 years... of heat, humidity, and salt-air... ;')

If total re-alignment is needed (likely), should I have the torsion bars "upped" by 2-clicks???

 

[RonD]

Yes, been there done that in my old Ford trucks.

They would/should have found that with an alignment

And it will stop wobbling if you turn the wheel one way or the other, not just slow down, which you didn't mention

 

[fixizin]

Uncle Gump: I've seen the cheap replacement wheel bearings fail with 10k on them.

Dang, that would be sad... but they were checked just 2 months ago, when the new tires were mounted. Supposedly they are 'Detroit Axle' brand, but I suppose Duh ChiComs counterfeit everything these days... bastiges.

ETA: what's kind of ironic is your wheels are mounted with 5 lugs, but the entire mass of the wheel/tire + hub/bearing + brake rotor is hanging on to the knuckle with only 3 bolts... lol.

 

[fixizin]

Yes, been there done that in my old Ford trucks.

They would/should have found that with an alignment

And it will stop wobbling if you turn the wheel one way or the other, not just slow down, which you didn't mention

Nope, tried S-swerving HARD, no luck, MUST slow down until there's not enough energy to sustain the oscillation--it's like a special case pendulum equation.

Actual alignment hasn't been done since ball joints replaced in 2012, about 34k miles ago, tie-rod ends still good back then... during recent tire change they just checked the angles... or maybe just spied the very even wear on my old tires and told themselves "she's fine, next!".

Read the horror stories of the F-250/350 version of this--it's a real non-obvious "gremlin" issue, with many owners making 3+ dealer visits to find a lasting fix... hence the eventual class-action lawsuit.

 

[19Walt93]

With the exception of trucks with loose front end parts, we fixed them all with different tires and alignments. All alignments aren't equal, there is an allowable range and high production tire shops will get them in range and ship the vehicle. You want everything set to "preferred". One of my former techs had decades of alignment experience, he said he could set up a front end "in the green"(allowable range on the screen) and you'd need tires within months.
My friend owned a Napa and had us put one of his new "value" line wheel bearings in his wife's Explorer, it lasted 4 months. Also, if one of my techs handed a customer parts that he decided to leave out of their vehicle he would have been a former tech before I was a former service manager. Find another shop ASAP.

 

[snoranger]

The F250/350 death wobble was usually caused by the track bar... Either the bushing at the frame or the ball joint at the diff housing.
We’ve found on our fleet that if it comes in with a death wobble complaint, (as long as everything is tight) just install a new track bar, track bar ball joint, and a shimmy shock. None of which you’re Ranger have.

 

[85_Ranger4x4]

My torsion bar F-150 was doing it. Only it would come and go.

I looked it over and found the newest lower balljoint on the truck was shot. Bingo, that is what is wrong. Replace that and it is as bad as ever but it doesn't go away now... crap I made it worse. Look the tire over good... and it was the tire. Apparently it would get into an occellation with the loose balljoint so it could do its own thing without shaking the truck sometimes.

 

[4x4junkie]

This is the first time I've heard of "death wobble" affecting any sort of IFS truck (indeed it's a sudden VERY violent shaking, often after hitting even a small bump)... Every time I've seen or experienced it has always been on vehicles having a solid-beam front axle.

Agreed though, suspension joints & bushings that are shot, bad shocks, loose parts and/or bad alignment are the usual culprits.

Keep us posted on what you find.

 

[fixizin]

First off, my "death" wobble is NOTHING like the borderline-loss-of-control, steering-wheel-sprained-my-wrist vids you can find on YT featuring F-250s and Jeeps... but it's bad enough, i.e. definitely going to put "accelerated wear" on more than just the tires, and damned uncomfortable too... but no problem maintaining control long enough to signal and pull over.

OTOH, got some "insider" info today that given the '99 Ranger particulars mentioned above (IFS/non-solid axle, no coil springs, etc.) it might just be air in the power steering fluid, turning the rack-and-pinion into a horizontal Bouncing Betty... did a few lock-to-lock turns in the parking lot before leaving work, and sure enough, my guaranteed 2 incidents per commute failed to surface... even sought out a few "known bad" manhole covers as attempted triggers--not a shudder... anyone got a spare SAGINAW PUMP for sale?

Still, going to take it in and get it checked out. With my rare combo of high-age and low-miles, there's always failures caused by "dry rot". My baby is sporting many red and blue replacement bushings, to remind me where the original black ones just disintegrated. (OTOH, weatherstrip/door seals still amazingly pliable at age 21...)

Will report back...

 

[fixizin]

My fave honest shop is a victim of its own success, and has thus picked up a ton of FLEET business (smart), so couldn't work me in on 12/18... other things to do today (still wobble-free)... will try again tomorrow, 12/20... probably just need a flush, fill with new ATF, and bleed... would someday like to do the Saginaw conversion, with a little inline cooler, maybe a filter w/ magnet too!

 

[fixizin]

OOOO-kay... procrastination, procrastinate, overtime @ work, MORE overtime... FINALLY got it into Duh Shop today, AND... they totally PUNTED!
Didn't charge me anything, but didn't do much either... they DID verify tie-rod ends and ball-joints OK, alignment still good, etc.

19Walt93 is right, I need a NEW SHOP--the gent who built it's great reputation cashed out and retired, and the young bucks have no stomach for diagnosing or fixing the non-obvious "one-offs".

Anyone got a good shop recommendation in the Fort Lauderdale/Pompano Beach/Plantation area??