I am having some problems with my 2009 pony package mustangs handling. I am having a problem with tramlining on grooved roads or roads with ruts. I have new lower front control arms, but the dealership said my tie rod ends were slightly worn, bur didn"t need to be replaced. I am also feeling a bouncing in the rear end. I want to upgrade my suspension eventually, shocks, struts, or caster camber plates, adjustable panhard bar. Possibly upper and lower adjustable control arms, but I dont feel like that would fix the steering problem, or the rear end shimmy, or bouncing. I am hoping someone can suggest what to do about the sloppy steering i am dealing with. I almost feel that the rear end problem has to do with the drive shaft. My car came with 18 inch wheels, I think they are 8 or 9 inches wide, anyway I would like to fix the problems I am having before I upgrade anything else.

 

What size tires you have in the front, what PSI you running and lastly what are your caster/camber settings? All three of those will affect tramlining to some degree.

Rear end shimmy could be a combination of rear shocks and worn bushings. It's rarely a driveshaft issue unless you've lowered the car or have other things that point towards it like noise.

 

Toe out will make a car drive "twitchy", which worn tierod ends would only make worse.

Wheel width (are they OE or aftermarket?) and tire size and make/model can also be involved.


Norm

 

I am still using the stock 18x8 wheels, with original size 235/50/R18 tires. The suspension is completely stock, it hasn't been lowered. I am assuming that caster, camber, toe in and toe out are correct since the alignment was done by a ford dealer. I guess i haven't even thought about tire pressure since the tpms isn't going off.

 

"Correct" with respect to alignment can be a somewhat fuzzy thing. There's 'factory preferred', which generally falls in the middle of some acceptable range - where anything within that range is acceptable provided that there aren't big differences, left side vs right side. There's also the matter of individual preference; settings that provide what you prefer might not be what I like at all and vice versa. Probably wouldn't be in the case of camber

I think a check of the condition of the rear LCA and PHB bushings is in order at this point. If they're in poor-ish condition, they may be contributing to what you're feeling and be reason enough to consider replacing them. Some things to consider with respect to rear suspension mods . . . don't bother replacing the PHB brace unless your car's OE PHB brace shows signs of damage . . . handling is not nearly as dependent on the rear UCA as it is on the LCAs, but the UCA does play a part in allowing/suppressing wheel hop . . . polyurethane bushings nearly always end up squeaking unless you're willing to modify it slightly before installation (I have some tips for this if you're interested, which may or may not come up on a search).

Norm

 

it doesn't take much free movement in "slightly worn" parts to make it feel all janky & such.

 

In my case the last thing left was alignment. Negative camber on my vehicle was still within spec but causing my inner front tires to wear out way faster than the rest of the tire. Installed caster, camber plates to reduce camber since there is no factory adjustment. That change alone fixed my tramlining and my inner tire wear.

 

Even with a well aligned car, grooved pavement can push or pull your car from side to side
depending on the evenness of the grooves. It is GROOVED, so, yeah, it can make the
car feel wonkey when you drive on them. We used to have a grooved end to the freeway
where I live. No matter what car I drove, it still swayed the car a little, because it was
old and the grooves were not even. It has since been paved over with asphalt, too many
complaints.

 

I'm not at all surprised to hear that "within spec" wasn't good enough for a specific individual's driving (I suspect that toe may have been a bit 'off' as well).


08 Dude - add open-grate metal bridge deck plates to the list of roadway conditions that nearly always cause woozy-feeling car handling. I know of exactly one make & model tire that was immune to this.


Norm