"Death wobble

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oldfardyfode

Junior Member
What causes The "Wobble" ??? A friend has put a new front end under his car....The 28 to 34 beam style front end.....4bar/ So-Cal stabilizer shock / 1/8 toe / 7 Degrees back / old style steering arm.....What can we effectively do to remedy his problem ????? It starts as acceleration hits 40 MPH and continues to 48 MPH.....When slowing down ( Decelerating) it starts at about 50 and gets wild till below 40 MPH.....I have changed and installed quite a few beam set-ups and Thank God I have never had this happen.....He says the car never once did it prior to the new front end....So can you guys HEP him out ??? I don't know what to do as it all measures right and noting looks messed up.....YET !!! Thanks, Cj./ Oldfardy Fode
 
Lots of things can cause the dreaded wooble. It starts from a tire or wheel bent or not balanced . Things that let it continue could be loose steering box mounts,play in steering box, slop in u joint in steering shaft. Check caster, camber, and king pin inclination. Do you have something like a trackbar? This is only a scratch on the surface of what can cause these problems. Good luck.
 
oldbugger said:
Lots of things can cause the dreaded wooble. It starts from a tire or wheel bent or not balanced . Things that let it continue could be loose steering box mounts,play in steering box, slop in u joint in steering shaft. Check caster, camber, and king pin inclination. Do you have something like a trackbar? This is only a scratch on the surface of what can cause these problems. Good luck.
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I AGREE;

There are lots of things that can cause what you are experiencing. I also would FIRST look very carefully at wheel balance or a bent wheel or a out of round tire. Beam axles are VERY sensitive to wheel balance.

Shocks are also critical.

Also check everything as suggested above.

Be sure to let us know what you find out.

Chris
 
Id start by checkingr looseparts.

Then id swapped the frontwheels /tires, Borrow a set from a car that works.
 
With a four bar you can add more caster, you can go up to 10 degrees. But I would check for loose or warn parts first. Sometimes it takes two guys, one to shake the front tire and the other to look for a lot of play somewhere, good luck Chuck.
 
With These old wheels, sometimes with adaptors or spacers its important to balance the whole rotating assembly, drums included. Good luck.
 
I see ALOT of "death wobble" threads on the HAMB...might try a search there...its covered.

or

Put the Ford parts back on...
 
When I first finished my Model A, stock front end 16in. tires, I went for a ride, the car handeled great untill I turned a corner and hit a bump in the road, the front end went into a saint vitus dance. I tightened the spring loaded tie rod ends and drag link ends real tight and then back them off one turn, put in the cotter pin, never had that problem in 10K mikes. Walt
 
This may sound too simple but by any chance did you check the alignment of the two kin pin bores in the axle with the two perch mount holes? All four must be inline. Also a line drawn through the king pin bore should intersect with the ground as close as possible to the center of the tire contact patch. Both sides. Sometimes an original axle that has been "dropped" does not meet this criteria. Don't know what you have for an axle but one or more of the mentioned fixes should help. Don't give up.
 
There are hundreds of different elements that create this wobble. When every thing is checked and the problem persists, do install a stabalizer between the frame and tie rod. You do not fool around with Mother Nature, and the same goes with Mother Physics. It's just the result you get with your particular car's setup. It's called 'Harmonics', learned that in the airplane world. Things start to happen without the understanding as to what causes it. Pick-up trucks with solid axles use dampeners, so I guess the autotive engineers have not found the source to correct either. My old '75 Eldorado, front wheel drive, had one....go figure. My '39 Flattie coupe with an original Mor-drop axle does not need one...runs perfect, so the only plausable answer is...Some need a stablizer, some don't.....and yes, it is pretty scary when at 40 mph, you have to either slam on the brakes, or hammer the gas pedal to get out of that situation.....Robert
 
Interesting stuff . Had this issue on a 34 4d and tightening the springs down in the tie rod - drag link ends cured it . Seems to be more to the story here though . Back in the dark ages i had a 1974 Ford F-250 4x4 that had enclosed knuckles in front filled with 140 gear lube . That truck started doing this also . Found nothing loose in the steering BUT the shock absorber on the tie rod was wet so after checking it { and replacing it } the truck never did it again . Thanks fer da info as this has always been a mystery to me . David J
Robert Dip said:
There are hundreds of different elements that create this wobble. When every thing is checked and the problem persists, do install a stabalizer between the frame and tie rod. You do not fool around with Mother Nature, and the same goes with Mother Physics. It's just the result you get with your particular car's setup. It's called 'Harmonics', learned that in the airplane world. Things start to happen without the understanding as to what causes it. Pick-up trucks with solid axles use dampeners, so I guess the autotive engineers have not found the source to correct either. My old '75 Eldorado, front wheel drive, had one....go figure. My '39 Flattie coupe with an original Mor-drop axle does not need one...runs perfect, so the only plausable answer is...Some need a stablizer, some don't.....and yes, it is pretty scary when at 40 mph, you have to either slam on the brakes, or hammer the gas pedal to get out of that situation.....Robert
Click to expand...
 
Walt Dupont--Me. said:
When I first finished my Model A, stock front end 16in. tires, I went for a ride, the car handeled great untill I turned a corner and hit a bump in the road, the front end went into a saint vitus dance. I tightened the spring loaded tie rod ends and drag link ends real tight and then back them off one turn, put in the cotter pin, never had that problem in 10K mikes. Walt
Click to expand...

Walt Dupont .....................
I did the exact same thing ! I would hit a bump in the road, with my '34 and it would "jitterbug", until I would come to a complete stop. I tightened my tie-rod ends and it hasn't happened since. That is the first thing that I would check.
MIKE :)
 
I had the death wobble on my 1950 F-1 truck. King pins and all other parts seem to be good. Replaced the bias-ply tires with radials, no problem since.
 
I opened a thread on this last week re my British Model B Cabriolet. Does anyone know if the steering stabilizer offer by Snyders....Part No A-3283....fits a Model B ?

I phoned Snyders but they didn't seem to know or were particularly interested
at 08.00 hrs.....if it does they have a VAST untapped market.

Their version looks like a reasonable piece of equipment whereas the MACS equivalent for a Model A would look more appropriate mounted on a bicycle handlebar.

Am I being too fussy ?
 
This was posted before but if you need information about alignment due to front wheel oscillations go to the Jalopy Journal web site, HAMB section, an do a search titled death wobble, there is a bunch off information on cures and causes.

The starting point is to insure that the axle is installed square to the centerline of the vehicle, one tire cannot lead the other tire.

Also when the tie rod is installed that the spindles where each positioned at 90* to the axle to get a true straight ahead track.

The next step is to make sure that you have no loose connections ie: tie rod ends. Followed by even air pressure in your tires 24-26 lbs for most light cars.

That the toe in is set correctly not to exceed 1/8" and caster is equal on both sides not to exceed 6* rear rake.

That both tires, wheels and drums are correctly balanced with no runout on the wheel.

You will need to recheck all these steps and not skip over any because you thought it was correct.
 
tiger.1000 said:
I opened a thread on this last week re my British Model B Cabriolet. Does anyone know if the steering stabilizer offer by Snyders....Part No A-3283....fits a Model B ?

I phoned Snyders but they didn't seem to know or were particularly interested
at 08.00 hrs.....if it does they have a VAST untapped market.

Their version looks like a reasonable piece of equipment whereas the MACS equivalent for a Model A would look more appropriate mounted on a bicycle handlebar.

Am I being too fussy ?
Click to expand...

Not sure about the axle clamps but it should fit. Save yourself some money though and buy a VW unit from any decent motor factors or ebay and make up a simple bracket to mount it. They are exactly the same as that Snyders part and also the So-Cal ones but only cost around £15-£20.
 
Thanks Gavin,

For a saving of say £75 on a unit which looks the part and hopefully fits it seems barely worth it....the cast aluminium brackets look more promising than the pressed steel variety from MACS ?

Looking at the Snyder unit they use the VW hydraulic ram but the castings and U-bolts look purpose made
 
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