Technical The search for a cure-Death Wobble SOLVED!

I noticed that after approx. 7,000 miles, I show some wear on the outside of the passenger side tire. The only thing i can think of is positive camber. This was a brand new CE axle, Posies spring and CE disc brake conversion. Other than bending the axle, is there a way to adjust this?

 

how much toe in does it have?

 

About an 1/8”.
.200” to my best estimate.

 

I have a set of tires on order. I think I may have them break down the tires and spin balance the wheel empty if that is possible. I have a spare set of brand new bare wheels in the rafters I could paint and mount up if it is out of round.

 

Hey Root,
If you think your tyres are out of round, try dropping the tyre pressure [a lot eg: to 15 psi]
This isn't good for longevity, but will help diagnose a problem.

Excessive toe-in is just pre-loading the suspension enough to prevent any wobble by getting the forces to fight each other.
see what happens when you toe-out the front wheels

 

I am really thinking I have maybe a bad tire or wheel. They have an insane amount of weight on one tire. I have a set of brand new steel wheels in the rafters that I am gonna paint up and mount the new tires on. If the problem goes away, then I'll use these old wheels for mock up etc.

I'll try dropping tire pressure and see what happens. Then I'll toe it out. I want to be methodical about it, because I really want to know what the fix is. I have a shorter CE leaf pack, but I am thinking it may raise it up like a Jeep Wagoneer. I'll just have to find it.

 

I have a CE front spring that's for the narrowed 47" axle. I borrowed the top leaf off of it. If you cannot find your I can bring it up on the way to the Roc.

I'd think a bad tire would be more likely than a wheel. Radial separation can't always be seen on the tire, but felt.

 

When I had a bad tire, the shake didn't come on 'til about 60 MPH and went away when I went back under.

Gary

 

This starts around 30 and gets progressively worse until 45 then I can drive out of it.

 

If you have a “

If you have an “ insane “amount of weights on a tire, it will never roll perfectly, because it has a problem! When I buy tires ,I watch how many weighs go on ! If the tire man starts stacking weighs on the tire, I tell them I don’t want that tire! Many times I have been told it won’t matter. So I tell them to put that tire on someone else’s car!
I will bet you that the new tires will fix your problem!






Bones

 

I sure hope so. The tires were balanced once before, but with the amount of weight they just installed, I am suspect. They should have been......

 

When I had the flat tire, in order to drive the roadster, I swapped out the wires for the 17" Salt Flats I had as rollers during the build (stolen from the Thunderbird project) until I got the flat tire repaired and the cause pinpointed. The have old, but never driven, modern profile radials, and have been on just used as rollers on the T'bird, the '52 DeSoto wagon, and the latest, the roadster.
When I had the tires mounted, the tire shop informed me that one of the rear ones, an 8" rim, had run-out that made it almost impossible to balance. They did so with, like the wheel you mention, with a lot of weight to try to compensate, and warned me that it might be felt driving, if they were on a small light car.
That was the case. At 55 mph, the car had a "shake" that made the steering wheel jiggle. Not a hint of a problem below that. I think on a heavier, larger car, they'd be OK. On my '51 Pontiac wagon I moved the rim on the rear tires, inboard on the centers as far as possible to get tire/fender clearance. One of them I must have bumped after getting the center "squared" in the rim, before or during welding, and it had a noticeable run-out, which like the Salt Flat wheel, made it difficult to spin balance, but on the wagon it didn't cause a noticeable problem. We put 75,000 miles on that car, two sets of tires, before it was totaled, with no issues at all.
The point of this long story is that it may indeed be a wheel, and not necessarily a front wheel. Check 'em all, or swap your wheels with the spares you have, and see if goes away.
Good luck...

 

It never hurts to have an extra set of rollers around.

The guys at the tire shop said they had to statically balance it before they could move on. I suspect that's the issue. I am hoping anyway.

 

Just don't post a photo of your car with temporary wheels and tires while you get things straightened out, that's not traditional.

 

Picked up my tires today. I’ll try and get the wheels painted in the next day or 2. Then back to the tire shop to get mounted and balanced. Crossing my fingers.

 

A few pages back somebody said - "They also had a little spring loaded scribe that they put a mark near the center of the tire , as it spun. They would just put it in the front and rear of the tire to measure toe in!
This method takes in consideration for a little tire run out, that they all have!"

Sounds just right to me. An accurate and reasonably precise refence to a plane perpendicular the asssembley"s axis of rotation is ground zero.

Some folks advocate free hand measurement with tape measures, or resting a couple of squares against the tire sidewalls on block 12" high and rolling the car forward a little bit.

Every time I've watched the edges of rotating on the car wheel rims ( even nicely machined alloy wheels) and tire features like tread or the sidewalls (even high dollar modern radials ) it is obvious any measurement based on them ain't likely to be better than ± 1/8", and maybe a bunch worse.

Radial runout of the installed tire tread needs to be less than 1/8" or so. Balancing won't fix that.
Gotta check (measure and record) the wheel runouts, selectively install the tire on the wheel to minimize their combined runout, and maybe even true the tire tread installed on the wheel.

Square wheel/tire assemblies can be balanced just fine, but won't roll very smoothly.

 

Well, I am happy to say that the death wobble is gone. It was a combination of things, but the last thing I did was to mount up a new tires on the wheels I had up in the attic.

We have a winner!

I believe @Mr48chev was the first to call it. Therefore, he wins a massage from @Tman.

This was very frustrating and laborious.
It drives a smooth as a gravy sammich now.

The only problem I have left is self induced. I ordered the wrong wheels. I ordered a set of Wheel Vintique smoothies, the rest are Wheel Vintique early oem vented style. The freaking hubcaps won’t fit!

Oh well, I’ll see if I can find something that will work.

 

Due to certain incidents I am no longer allowed across Washington State lines