Look at the drag link size ( diameter of the rod ) If its to small it will flex and give you a wobble. That is what was wrong with mine. you can stiffin it up or buy a bigger rod. Thats how I fixed mine.
just when i go over bad places in the road at low to stop speed, like going up to a stop sign, or light ,hit a bad spot shakes out your teeth, low speed to stop. use the brake alittle when coming to a stop, or slowing down, no problem....
Have you installed the Thorkle Rod correctly? If so, was it torqued to .007 nM laterally and 23.046 MB lbs with tapered Kelvenator bushings at 18 degrees C? If you did not then you will need a new Thorkle Rod repair kit. Send me $250.00 cash for plain or $500.00 for chrome plated Stainless is $1,000.00 for each side. Don't feel to bad if you installed it incorrectly most people don't know how to install it, maintain it, nor can they even point one out on your car. Could be a bent axle
I took off my bias coker firestone tires and replaced with coker radial firestone F540 145 Radials. Problem solved.
I second that. The fact that everything tightens-up when the brakes are applied gives the wheel bearing solution credibilty.
Flathead31coupe I thought that you got this squared away last year. Anyway from the multiple posts you have described a low speed wobble meaning the wheels wiggle side to side at a slow speed range. To help isolate the issue that causes this problem you will have to go over the alignment of your axle very carefully. I am also assuming that you have installed a panard rod to locate the front axle correctly. Side to side wobble is created as the rolling tire tries to center it self on the king pin axis. In many cases it can be traced back to uneven caster split meaning that one side of the axle has much more or less induced caster than the opposite side. (like your race car observation) You should carefully check that the axle caster is equal at both sides of the vehicle and should be in the range of 4-7* tipped rearward and not to exceed 7* less is better in my opinion. You should also check to see that there is not an excessive caster twisted into the axle from the leverage of the upper steering arm. (not usually but this is a trouble shoot). This happens in old style dropped axles where the drop narrows the beam width. The next area to address is the square of the axle to the chassis. This is important because it determines the tire contact patch side to side relationship. The tire contact patch must be on the same lateral line tire to tire. If the axle is positioned in the chassis at an angle this places one tire contact patch ahead or behind the other tire contact patch and the tires attempt to seek their own centering forces, which at low speed interpret as a wobble. At higher revolution the gyro effect cancels this out and turns this into tire scrub. It is important to measure the position of the axle and insure that it is square to a centerline of the vehicle and rear axle. Even thought you set the toe in the tires are not centered on the same lateral. The last suggestion for now is the relationship of the steering arms. It appears from your picture that you have bent a stock steering arm down to clear the wishbone drop. Doing this moves the steer center further from the horizontal axle center line. This now exaggerates the toe in/out of the RH steer spindle as it travels thru a small arc meaning some of your side to side wobble is being incited as the tires try to recenter. Anyway this will keep you busy for awhile.
may be a stupid response but broken motor mount? <input id="gwProxy" type="hidden"><!--Session data--><input onclick="jsCall();" id="jsProxy" type="hidden">
Just another thought ? , a guy here had a issue on his bucket ,but developed the wobble after many years on the road ,went through everything ,The problem was a slight buckle in a rim ,that was caused ,they think by some one backing into it at work. Something else to check , jump up & down on the front, chassis if ya can ,what happens with the wheels ?
If those tires are Cokers it might be the problem. Had it happen to me. Just for kicks i put the Cokers on a differant car, same thing.
i know tires can do funny things, this might not be your problem but it might play a role, i had an 80's mustang that pulled so hard to side of the road you couldn't take your hands off the wheel for a second, one day it had a flat on the drivers front and i put the spare on, no more pull to the side of the road, i pluged that tire and put it on the passenges front, now the car pulled like a bastard to the center of the road, never figured out what was the tires problem, it looked fine, tires can be funny.
The first thing I would be doing would be to jack up that front end and check the run out of the rims and tyres. Simply get a jack stand and clamp a screwdriver to it to use as a pointer and place it against the rim bead and see if it runs true or not. In a similar way check the tyre for concentricity by putting that same pointer against the centre of the tyre and spin the wheel. In either case if the show runout then either change tyres or rims until they run true. The rims and tyres running true are fundamental to the smooth operation of any front end. You must eliminate this as a possibility.
Fitzee and Spadero always have sound tips. I fitted out a new dropped axle, and found that the kingpin bushings were "loosely" sized, even industrial "thick" grease didn't cure the wobble, in this case, when brakes were applied. If either tire encountered a greater resistance, as in rough surface/bump/pothole/stone, it sounds like just enough to induce the vibration. I'm voting with either the loose component, or the tire/rim imbalance. At least what you've described sounds like a "system" that is triggered by the rough patch of road, and the oscillation increases, rather than being damped out (NOT just by shocks or a steering damper).
I've had that happen to me with the coupe in my avatar, but in almost two years it's only happened about 3 times. I have no idea.
death wobble can be a bit tricky to diagnose. Find some one locally that deals with straight axles (or live axle 4X4s) that will go through the whole front end piece by and check overall geometry. Sometimes you need to acknowledge when your in over your head and leave it to the pros.
I'd check those wheel bearings again. Just a suggestion as you hadn't mentioned checking the bearings. Bud
My Tie rod would flex before I stiffened it when would pull in on the tires from the center. It would bow in a bit. How sturdy is your tie rod?
I had driven my car for 4 years and never had a wobble until last November....the right wheel would bounce up and down if I hit a bump at 55-60 miles an hour. Come to find out I only had 15 pounds of air in my fronts. Put the 32 lbs in them and it stopped and I also put on new front spring bushings. Its a weird feeling when it starts that bouncing.....
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