The short is that I've now got new tires and they helped -- I don't get anymore left/right effects. However, one of the original problems (darts with ruts) still remains.
This has been frustrating since I get to experience wihat correct handling feels like for a little while before it goes bad again -- I feel it, I like it, I want it permanently.
The new (matched) tires helped
tons. I went with Goodyear Assurance TripelTred's in a 195/70 size, in case anyone is interested. All the previous work has also enabled me to narrow down the rut-darting problem to being solely with the passenger front wheel -- no other wheel causes the darting behavior.
At this point, there's really only a few things left it could be:
- Wheel bearings
- Lower ball joint
- Lower control arm bushings
- "Break" ball joint (the one mounted just under the passenger's feet)
- "Break" bushings (where the tube mounts to the LCA)
- Spring or spring pads (?)
Symptom: car darts to left or right when the front pass tire goes over a sharp-edged rut with the edge nearly parallel to travel direction. Jack the car up for a while and problem disappears. Problem gradually reappears over about 100 miles (accumulated over several trips). There is no associated steering pull I can tell, but rolling friction seems higher when the problem returns.
I'm still thinking LCA bushing or lower ball joint as none of the rest seem like they would have such a long delay in effect nor an effect without related steering pull.
Interstingly, and probably related, is that the upper ball joint on that side had radial wear, but only in the direction perpendicular to the side of the car. I couldn't tell that until I cut it open, but I did, so I know.
I'm betting that that wear pattern is matched by a similar movement in the lower side of the wheel somewhere. I checked the lower ball joint last night and couldn't detect any play in any direction. I need to check the LCA bushing this weekend. My indie pretty much dismissed that bushing because "there wasn't any rust falling out of it", so maybe that's not it either.
We'll see.
TomW (check the rear sway bar links):
Thanks for the suggestion. I haven't looked at the rear sway bar links yet (keep meaning to), but the mechanic didn't find them bad and, well, things are much better now. The back end seems totally fine now, its just this front pass wheel problem. I'll check them at some point, but suspect they may be OK enough.
RLeo (ideal 1/4 mile tracker):
Not anymore. The car no longer pulls post alignment and with four equal-sized tires on it, it wants to go straight.
obiwanrazzy:
Nice to hear my saga is helping someone out there
As for the "single" thing that made the most difference, it was having the indie replace the tie rods, drag link and shocks, and doing an alignment. New tires was the next bigest change -- no more mushy handling and wierd wandering. However, everything I'd done till then got done slowly enough that I was able to feel the (sometimes slight) improvement in handling between each item. In other words, they all helped, and I doubt starting with the tie rods/drag link/shocks/alignment or the tires would have made as much of a difference without all the other fixes first.
I started by checking tire pressure (but not size and brand/model). When that didn't help, I jacked up the front end and checking for visible play in anything. It sounds like that's probably the next thing for you to do -- no sense getting an alignment on worn suspension, and new tires on a bad alignment is a waste of good rubber.