Occasionally my car like hits a groove and shakes like crazy in the front. The tires are 4.50 Firestone (bias ply on 35 wires) old style front end with original style shocks, reversed eye leaves and 4" drop. Usually this shaking happens going around 30 - 40 mph and will not stop until I speed up to 55 - 60 or almost come to a complete stop. What should I do .... Thank you, Guy / Dallas
Before you go get more confused do a search like 36-3w suggested. There are a couple of threads on this issue, read all the one with that is ***led "death wobble" I cant remember the actual name but it was started by ----31---. This will point you in a direction to help solve your issue.
I've had this problem with hot rods with reversed front wheels, but that doesn't sound like your problem. Double check your specs, (1/8 toe in, 6-9 degrees caster, zero camber) as well as kingpin fit. My gues iss something is loose or worn, or out of square with the ch***is. Maybe measure your wheelbase on both sides to see if something's amiss there. You'd be surprised how many cars wheelbase is an inch and a half off, side-to-side.
Guy Check the king pin bushings for wear. Jack up the front end ubtil the wheels are off the ground and shake the heck out of the wheels - see if you feel anything that has excess play. Early straight axle Fords had this problem when excessive play developed either in the king pins or the steering connections. Also check caster - 4 to 7 degrees works some fellas run even more). Hope this helps Bill
Sounds like the caster angle is out... (Like the shopping cart wheels that wobble like crazy) it used to happen on my 32, so bad that one time it broke the steering arm. (I was going real slow at the time...phew!) It had the original radius rods on the front (split) but the mounts were at the wrong length where they connected to the frame so it changed the caster. It used to happen to me at slower speeds and a bump in the road would trigger it, it got so I could predict when it would happen. Sometimes I could stop it by slamming on the brakes. I took it to the local Ford garage and they bent the **** out of the radius rods trying to get the caster alignment near specs... When I redid the car with a P&J 4-bar, it never did it again
Tractors and trucks suffer from the same Death Wobble. There's usually a bit of slack somewhere that's at fault, along with some outside influence, like a stretch of rough road. It seems the more solid mounted the axle is, the worse it gets. Cushy rubber spring bushings seem to damp it out of newer I beam setups. Tilting the axle back a few degrees usually gets rid of most of the problem.
My car did this after I lowered it. I would hit a bump and the front end would shake like crazy every once and a while. I shortened the stock Model A pitman arm and droped the aftermarket steering hoop down and it seemed to cure the problem. It made the drag link more parrallel to the wishbone. Before: After:
A car that doesn't have enough caster is usually a handful to drive, darting with the road service and generally making life miserable and tiring behind the wheel. You likely have worn kingpin bushings, worn or loose tie rod ends, especially if they are the original adjustable spring and ball seat style, or heim joints. And it wouldn't hurt to have your tires checked for balance and out-of-round. AND check your shocks and see that they havefluid in them and are working. AND while you're there drop the pitman arm and adjust the steering box by the book. It never hurts to check everything around a problem while you're working on the problem, often finds potential problems.
This usually gets some negative replys but put a steering dampener on it. So-Cal sells one that works fine. It's actually a WV dampener but comes with the hardware to hook it up. This usually cures the problem (or makes it go away). So-Cal puts one on every car they build just to forgo the problem. Oh yea, check everything that's already been mentioned but if the problem persists put the dampener on and enjoy your car. Frank
The Jalopy Journal
