The best thing to do is have the car inspected by a suspension and alignment specialist. Sears used to offer this service for free. Don't know if they still do that.
I doubt the tie rod ends are the problem because your mechanic would not have been able to set the final adjustment, "toe". Part of the procedure is to make the adjustment to each front wheel, then rock the steering wheel, then center it and recheck the numbers. The readings would be all messed up if the tie rod ends were loose or sloppy. However, ... A loose rack and pinion can easily be overlooked because often it takes road forces to make it shift position. This is something you have to really look for, as I mentioned, by rocking the steering wheel. It's funny the mechanic didn't notice something wrong on his final test drive after performing the alignment.
My concern is your description of the car going in different directions based on road conditions. That is caused by something much bigger than just worn parts. Besides the loose rack and pinion assembly, that's why I mentioned loose lower strut mounting bolts. A few different things can happen and they're related to replacing the struts. Rust and dirt can build up on the threads of the bolts. It is possible for that to make the nuts feel tight to the mechanic when they haven't really clamped the strut in place sufficiently. That may not show up right away, but after a few good potholes parts will start to move. Eventually enough metal can be ground away that the strut moves easily. That will allow the top of the tire to move left or right as viewed from in front of the car. As the tire leans one way or the other, it tends to want to roll in the direction it's leaning. It also changes the relationship to the steering linkages, (including the tie rod ends), which causes that tire to turn left or right. The car goes that way so you have to turn the steering wheel to counteract it.
I don't mean to imply your mechanic(s) didn't know what he was doing, but I ran into a problem once when we were so backed up, a well-meaning coworker installed the struts for me then sent the car to me for the alignmment. After making all the normal adjustments, I bounced the car to settle the suspension, and both tires flopped in on top. I didn't have those bolts tight enough. Reset everything, tightened the bolts a lot and the same thing happened! Got mad and REALLY tightened those bolts until I snapped one by hand. These are huge bolts and I ain't that strong. When I took the wheel off to replace the bolt, I found that the other guy used anti-sieze compound to prevent future rust and to be sure I could get those bolts free years later. Nice thought but anti-sieze compound destroys the friction that is needed to keep parts from moving when they are clamped together. Had to clean all that stuff off, then just use plain old grease to do the same thing. The point of my story is if that problem hadn't shown up on the alignment rack, it would have during the final test drive and would have been real miserable to drive. Even worse, it might have not shown up until the customer was driving it. Those are the types of things that can go wrong to even the best mechanics.
Same thing with the loose rack and pinion assembly. Once it shifts position, a little metal is worn away. That makes is a little looser so it can shift position easier next time. As that keeps happening, the car gets harder to control and it acts up over increasingly smaller bumps and dips in the road.
One more thing you can look for is worn upper strut mounts. They are normally only checked when the old strut is removed, but it is possible to change the strut without seeing the wear, especially if you don't make the extra effort to inspect them. The center hole that the shaft of the strut goes through can rust away and allow the top of the strut to move back and forth. That too will allow the top of the tire to tip in or out although not a real lot. The upper mounts are always near the hood hinges, slightly further back than the point the tire contacts the ground. They are bolted under the body sheet metal with four, three, or sometimes even with only two nuts. In the center of that assembly is a much larger nut. You might have to remove a plastic trim cap to see it. That nut is normally centered in the mount. If it can shift position, it will change the alignment and the handling characteristics of the car. The weight of the car is on that mount, but the strut can move fairly easily when bouncing down the road if the hole is rusted larger. In some cases you can identify it as the cause by prying the nut back and forth with a pry bar or large screwdriver. You might also see "witness marks". That is shiny spots that indicate parts have been sliding across each other. Another clue if you can find it is to check the position of those nuts at various times and see that they have moved. This is grasping at straws in hopes of finding something, but it's not something to overlook. From your description, I don't think the upper mounts can cause that much trouble. My vote is for a loose rack and pinion assembly. I've driven a few cars with loose racks, and it's not fun.
Caradiodoc
Tuesday, April 20th, 2010 AT 9:42 PM
