Alignment question

So the kid's 2000 Focus sedan pulls to the right when accelerating, and to the left when braking. He's got the Central Flordia Motors el cheapo camber plates on it (a rotating disc to pull the strut in or out).

The local Firestone did an alignment on it, with caster at 2 deg on one side, 3 deg on the other.

My very limited knowledge of caster says it's what makes the car want to steer straight (for lack of a better term); would the varying degrees of caster cause his car to do that?

Steady state driving it pull a little right.

Help!

Yeah, absolutely. It's like the car is always trying to dog-leg diagonally. One front wheel is closer to the front of the car than the other one.

I had a bent front control arm on my WRX that knocked the caster back half a degree on the right side and it had a tendency to wander on badly crowned roads and had periodic steering numbness under certain circumstances while turning. Really unnerving.

I'd look for a worn control arm bushing that allows one of the wheels to move fore and aft. Toe change can certainly cause that.

In reply to Streetwiseguy:

Yeah, it sounds like bad parts to me. Or possibly the combination of alignment and a bad brake caliper. That caster spread is pretty major as well. Could be pulling one way because of that and the other way during braking because one caliper is hung up. But I'd still bet on bad parts that are allowing an alignment change between accel and braking.

Or, with the braking, it could be bad brake lines or just a sticky caliper.

It is probably a bad motor mount. That does loopy things under acceleration in a front driver. Caster pretty much does nothing on a FWD strut car until the change is dramatic (like five degrees difference) or it changes signs left to right.

I have also seen, on early VWs, very minor included angle differences causing all sorts of weird problems. Probably not so much a Focus, and included angle is nonadjustable anyway.

Speaking of which, I have never had good luck with directional tires on a FWD car. Which especially sucks since it seems any tire that isn't a generic POS tire is going to be directional.

Semantics, pull vs. drift: A pull wants to tear the steering wheel out of your hands and keep turning. Think like driving on a very low or flat tire. A drift has the car want to take a set slightly off of straight ahead. Think driving on a cambered road. Biggest peeve: People who say an offcenter steering wheel makes the car pull. If you can take your hands off and the car still goes straight, it drives straight.

In reply to OldGray320i:

Caster will pull to the side that is least positive. On a front wheel drive, the caster should be the same side to side unless the specs call for unequal caster settings. You did not state which side the readings were on. That being said, I would agree w/others about lower control arm bushings. Usually the rear bushing since it takes the most load. That will cause the caster, camber and toe to change on acceleration and braking.

2000 focus kiddo here.

at streetwise, LCA's bushings were replaced recently and that fixed a similar issue. they are POLY now and still appear to be fine.

at blue mustang guy, im assuming you are probably right, the problem did arise when i put the plates on. or atleast onto something. still need to find out what is the best way to adjust these plates. i just threw them on and followed the directions for 1* of camber.

doesnt feel like a dragging/sticking brake issue as ive had those before and fixed it. as well as E36 M3ty lines before. have SS lines now.

its USUALLY more of a drift still some of that pull category in there; though there has been times where itll make a lound clunk driver side by the clutch pedal and pulled hard.

Loose subframe?

OldGray320i wrote: So the kid's 2000 Focus sedan pulls to the right when accelerating, and to the left when braking. He's got the Central Flordia Motors el cheapo camber plates on it (a rotating disc to pull the strut in or out).

And those camber plates are the problem. BTDT. That design (and all similar ones) rotate to change the camber. Unfortunately that also changes the caster which is causing your problem.

Ditch the camber plates (or get a better design) and use "crash bolts" (fit in LCA) to fix any camber problems.

Control arm bushings are poly, he just put them in. Brakes were a-ok prior to installation of the camber plates (i.e. no pull or funkiness). That, to me, points to the alignment/camber plates.

IRT Hal, I realized that they'd change camber and caster at the same time, but I should think that once set, they should be relatively ok.

Since you drive (or did) a Focus of the same vintage as the boy's, can you advise on the "crash bolts" to use? I can't visualize how they'd work for the Focus here.... I didn't see anything else for camber adjustment at the time I picked these up for him.

The crash bolts are eccentric bolts used to replace the bolt on front of the lower control arm. They usually can be purchased from a Ford dealer as they are used in crash repairs. They do not provide much (.5° to .7°). A better solution is racing type camber plate . Capaldi Racing also used to make one.

So turns out the strut bearings needed some help (let's just say it's not really an "optional" item for installation... kids these days). Needs realigned a bit again, but otherwise is ok now. I wouldn't have guessed the car would do what it did as a result.

Hal, thanks for the tip on the crash bolts; that'll be at least a bit of an option if at some point he decides to lose the plates.

OldGray320i wrote: So turns out the strut bearings needed some help (let's just say it's not really an "optional" item for installation... kids these days).

Oops! Yeah, any time you take the front suspension apart it is almost mandatory to replace the strut bearings.