Front end geometry

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Coyote Jack

Coyote Jack

Member #55, I'm old
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I have had 2 summers of driving the Demon. The whole time I have suspected that I have a front end problem, but couldn't find it. Here are the symptoms.
1. When I drive down the road the car will twitch on it's own. Mostly to the left but sometimes to the right.
2. When I hit WOT from a dead stop the car will pull hard to the left and when I let off it wants to go right.
3. On some corners the front tires will squeel.
4. Even though the front end was lined up the steering wheel is off of center to the left.
I suspect this is a bump steer problem. Although I have not been able to check the lengths of the tierods due to the cold weather lately, that is where I am going to start this time. If they are not the same length, would that cause this problem? What are other things I should look for? Is there any way that the home mechanic with out special tools can cure or at least get it close and then get an alignment done?

I have standard steering with a stock steering box, radial front tires and M/T Sprortsman pros on the back. I also have a spool rearend. I don't drive the car in the rain and I am used to the understeer caused by the spool. All of the frontend joints and bushings were new less than 2000 miles ago except the Pitman arm which was good.

Any help would be greatly appreciated as this car is a real bear to drive right now.

Jack
 
nearly all A bodies suffer from not enough Caster. This sounds like a symptom. Tubular upper control arms will remedy the issue by putting in 3 degree of caster while maintaiing the camber. CAP Auto products sell them as do others. They work regardless of what brand or manufacturer.

www.capautoproducts.com


Ray
 
Doesn't sound like a bump steer problem....

A couple of things you can try:

Swap 2 front tires side to side and drive again. See if the pull at WOT changes at all.

Also, you can measure wheelbase front to back on both sides.
 
also check the pins that hold the leaf spring segments together. and also recheck the idler arm,have someone move the steering wheel back and forth while you look at it.and have the alignment rechecked now that the new bushings have all settled it could have changed.hope this helps!
 
I'm guessing its all resulting from the spool rear.
 
Check your lower controll arm piviot where it goes into the k frame. The weld is known to crack. I had a 72 Demon that had that problem. I bumped a curb backing out of the driveway one day, it cracked and then it drove EXACTLY like you are describing. Took the torsion bar and lower a arm out, rewelded, problem solved!! Good luck and let us know how it works out!
 
replicaracer43 said:
Check your lower controll arm piviot where it goes into the k frame. The weld is known to crack. I had a 72 Demon that had that problem. I bumped a curb backing out of the driveway one day, it cracked and then it drove EXACTLY like you are describing. Took the torsion bar and lower a arm out, rewelded, problem solved!! Good luck and let us know how it works out!
Click to expand...

I will check for that. Unfortunately I won't be able to test drive it for a few months. It's winter here.

Jack
 
The brakes are brand new disk. All parts new. I rebuilt the entire frontend on this car trying to avoid this kind of problem. So much for that plan. LOL

Jack
 
After u check for the obvious broke welds etc. and check that the steering box is bolted on tight. Have the car aligned and go for at least 3* positive caster. In order to get it on mine I not only put the offset bushings on i also cut the strut rod bushings and spacers down. I have a 20-1 manual box with 225-50-15 on the front and it drives like a dream. It's only hard to turn when its not moving.I only have a 14" steering wheel to. Sway bars will also make it drive a lot nicer. Good luck.
 
check everything. steering box, upper and lower bushings,upper and lower ball joints, cracks in the k-frame. there is no reason a stock suspension should do any of that. something is definatley worn,broken or installed wrong.
 
If there is a broken weld or crack in the areas mentioned, then you would have a tire wear problem due to the alignment shifting. How are the tires wearing?
 
They are wearing on the inside, but they were that way when I put them on. Just getting all the wear out of them before I get new ones this spring. Supposed to get to -20F here this weekend, so I guess this problem is going to have to wait.

Thanks everybody for the suggestions. I will be checking everything. I sure didn't want to take tis front end apart again, but that is what is going to happen.

Jack
 
Just a thought but I had a Dart that didn't like radials on the front and bias tires on the rear. It drove a little weird when cornering and when I punched it. It drove great after switching to all radials.
Bob
 
What kinf of shop was it aligned at?,if at all possible it should be aligned by someone with alot of experience with older cars and prefferably mopars.You cant cure the camber/caster problem without changing parts but a good tech can compensate and at least make it drive good.I would be leary if the wheel is off,that can be a sign it was a quicky or improper job.I agree with everyone on checking everything thoughly first and going from there.
 
I hate to say it but you might want to pull the rear axels and make sure they are "happy"
 
#3; front end, something is worn or loose. Or your front end guy has no clue how to check or align it.
 
Coyote Jack said:
They are wearing on the inside, but they were that way when I put them on. Just getting all the wear out of them before I get new ones this spring. Supposed to get to -20F here this weekend, so I guess this problem is going to have to wait.

Thanks everybody for the suggestions. I will be checking everything. I sure didn't want to take tis front end apart again, but that is what is going to happen.

Jack
Click to expand...


It's real hard to get the car lined up good w/worn tires. That may make it drive like you are describing. Also if you can't get some possitive caster it makes it drive funny.
 
Not being able to adjust enough positive caster in our A-bodies is a normal situation with stock parts and it does make it steer kinda funny but nothing like what your describing.

Back when I rebuilt the front end on mine and took it to be aligned the guy knew them real well and did the best he could but the best caster was -1.7 degrees. That's about 3 degrees less that what it should be. It drives real straight and doesn't wear the tires and the only thing it does not do right is it doesn't return to center when turning corners.

To make sure they can adjust in enough caster you need to either install offset UCA bushings to force more caster or install tubular control arms that have adjustable rod ends to get the extra caster you need.
 
Was the alignment done with the worn tires?Maybe it,s a belt shift on the worn tires.You,ve got 5 months to save for new tires.Only in Canada EH!!Put new tires on and get the frontend checked again.Good Luck!Let us know in the spring?
 
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