Bump steer-can it bee this bad?

[Loubo40]

Bump steer-can it be this bad?

i have a 67 coronet, sits just a bit lower than stock. if i set my toe properly (0-1/8 toe in) while sitting at ride height, the tires squeal while driving. it appears the rise in the front end while under power puts the tires toe in.

what i have done to get by, is jack the nose up an inch or so, and set the toe like that. when i let the car back down the tires toe out, but it seems to work best like this for normal driving. when im on the gas hard the tires are screaming from what seems like excessive toe in.

all the front end components are good.

I am having this aligned in the next few days/weeks as time allows, but im not sure anything they will do will change this.

does anyone else have this problem, can the factory geometry have this bad of a bumpsteer problem?

any insight on this would be greatly appreciated.

thanks

 

[Loubo40]

i apparently have a unique B body front suspension

 

[benno440]

toe should be set at ride height, stock mopar suspension did not have very good geometry, maybe some upgrades are in your future

 

[Loubo40]

toe should be set at ride height, stock mopar suspension did not have very good geometry, maybe some upgrades are in your future

If I set the toe at ride height the car is nearly undrivable, the from tires start to sqeal as soon as it step on the gas and the nose rises a bit. I really can't understand how toe can change so drastically with so little suspension movement. Something has to be wrong.

I would love to upgrade but it's a numbers matching car with under 10,000 miles and I wouldn't want to modify it.

I'm hoping to sell this when it's finished and get something that I can make modify to make it a real nice driver.

 

[benno440]

that seems to be really excessive bump steer, must be something wrong with a component. to minimise bump steer, you would draw an imaginary line through the UCA mount, LCA mount and your tie rod mount, then another imaginary line through your UCA, LCA and tie rod end where it mounts wheel side, this would be 0 bump steer, stock suspension has some bump steer built in.
But it should be set at ride height, are you sure you are doing it correctly?, undo both tie rods, get your steering centred, run a string line off your frame equally and get your driver side wheel straight forward, then measure over to passenger wheel get it straight, then reconnect your tie rods and start your toe again, try this would be my first recommendation

 

[Cranky]

toe should be set at ride height, stock mopar suspension did not have very good geometry, maybe some upgrades are in your future

'A' body cars have a problem with getting enough caster but I've never had a problem with B body cars....even lowered below stock ride height. Also, I never cared for stock alignment settings and go for more camber and caster and still use a minimal amount of toe in with good results. Last couple of times I let a shop do my alignment, they dialed in way too much toe in and that will usually have the results you are seeing. Are you sure you're seeing too much toe out?

 

[Loubo40]

'A' body cars have a problem with getting enough caster but I've never had a problem with B body cars....even lowered below stock ride height. Also, I never cared for stock alignment settings and go for more camber and caster and still use a minimal amount of toe in with good results. Last couple of times I let a shop do my alignment, they dialed in way too much toe in and that will usually have the results you are seeing. Are you sure you're seeing too much toe out?

i believe the squeal i hear is from toe in with the nose raised under acceleration. when the car sits at ride height, i have to set nearly 1/2" toe out to get satisfactory results while driving. with this much toe out at ride height, just raising the nose 1" brings me to zero toe.

i did install offset bushings to maximize caster as the wheel was not returning to center before i did.

 

[cdr]

it sounds like someone did some mods & installed the outer tie rods from the top side of the ball joint, the outers should come in from the bottom.

 

[kb67mopar]

Something is definitely wrong in your setup. You should not see a large change in toe with a 1" change in height. I'd pull everything apart and make sure it is installed correct, that bushings and joints are good and not loose or worn. Then get a manual and make sure the components are in the proper orientation as cdr just said above.

something isn't right and I suggest putting it back to factory specs and removing whatever spacers you added. Clearly something is amiss and the factory componentry does work.

 

[Loubo40]

it sounds like someone did some mods & installed the outer tie rods from the top side of the ball joint, the outers should come in from the bottom.

i wish it was that simple, outers come in from the bottom for sure.

 

[Loubo40]

Something is definitely wrong in your setup. You should not see a large change in toe with a 1" change in height. I'd pull everything apart and make sure it is installed correct, that bushings and joints are good and not loose or worn. Then get a manual and make sure the components are in the proper orientation as cdr just said above.

something isn't right and I suggest putting it back to factory specs and removing whatever spacers you added. Clearly something is amiss and the factory componentry does work.

the only thing that has not been checked/replaced are the lower control arm bushings, i guess i should move to those next. of course those require complete dis-assembly of everything...we shall see.

 

[kb67mopar]

the only thing that has not been checked/replaced are the lower control arm bushings, i guess i should move to those next. of course those require complete dis-assembly of everything...we shall see.

If they are like mine were they are TRASHED. One of mine fell apart once I got it out. I bet yours are not in great shape.

 

[67 coronet]

if that lower bushing is trashed it will throw your alignment all over the place as it moves back and forth under load.http://www.allpar.com/history/mopar/front-end-alignment.html
here is some more great info for ya.

 

[nm9stheham]

Does you car have a deep sump oil pan? If so, see if the pitman and idler arms have been bent down or moved down to accomodate that. If so, that will mess up the bump steer. The tow movement you seem to be reporting is waaaaay out of whack.

 

[Hemi Rebel]

How bout some pictures of the steering parts at ride height.

 

[badmopar67]

Sounds like lower control arm bushings are bad

 

[AMX364]

Silly question, how did you check toe? Did you scribe a line in the center of the tire and measure from the front and back? Or did you measure to the inner edge of the tire? Or use something that is designed to measure toe?

 

[Loubo40]

Silly question, how did you check toe? Did you scribe a line in the center of the tire and measure from the front and back? Or did you measure to the inner edge of the tire? Or use something that is designed to measure toe?

I measure front and back of the tire from the same Tread row.

 

[Mr.SpeedFreak]

IMO if you're rebuilding the front suspension, replacing the LCA bushings should definitely be included. Mine basically had the entire bottom half worn away on each one lol. Whether or not it has anything to do with your bump steer issue, it should still be checked. Take one more element out of the equation.

 

[sleepar]

I'm having a simular problem chasing tow and keeping the wheels straight it can be confusing but with any part installed wrong or miss aligned will throw you off... castor and camber after the height is set then after everything has been bounced a few times and settles adjust toe