Loose strut/shaking?

Pictures aren't posting for now as the site is going through some updates, but to address the bolt size, we never ask that because they are special bolts you won't find in a hardware store. Some designs, GM in particular, often don't even have a hex head. They have two flats for an open-end wrench, and splines under the head to keep the bolt from spinning while you tighten the nut. Some designs have an enlarged shank right under the head. Some older designs, Chrysler in particular, have an offset head that allows for easy and accurate "camber" adjustment during the alignment. Almost every manufacturer uses their own special sizes, shapes, and hardness.

Your best option is to get the bolts from a pick-your-own-parts salvage yard. "Pull-A-Part" is one very nice chain I've been to. You can do a search to see if there's a yard near you. There's a lot of similar yards popping up. Also, when they scrap a car and remove the struts, they usually throw the bolts out for scrap metal. The people at some yards will give you the bolts if they can find some.

Wow. I looked it up and you're right, they are hex bolts, but not used in a manner that's common. In fact, I've been a suspension and alignment specialist for over 40 years, and have only done this procedure on the back of Ford-built 1980s Escort "killer cars".

They show a chart with four different bolts, but they don't say if they're simply different diameters or if the heads are offset different amounts. The Chrysler bolts I mentioned had offset heads that sat in a pocket. As you slowly rotated them, they moved the spindle in or out on top to set "camber". That's how much the wheel tips in or out on top, as viewed from in front of the car. You could do that on GM models too, but you had to buy those bolts from aftermarket suppliers. To my knowledge, the only other manufacturer that came close was Toyota, but they did the adjustment with an offset insert inside the bolt hole in the spindle. It was a lot of disassembly and trial and error, over and over to get it right, but when you did, that adjustment couldn't slip on bumpy roads.

What I would suggest first is to raise that tire off the ground, then see if you can push it in and out on top. If you're able to move it very little, snug the nuts, then drive the car to see if it pulls one way when you let go of the steering wheel, and if the steering wheel is straight. If that's what you find, the last observation is tire wear, but that takes time to show up. If the alignment is not correct, don't try to fix it yourself. Take the car back to the shop that did the work so they can do the alignment over. That will typically be at no charge to you, as long as you don't wait too long.

Reading the alignment procedure, it is apparent the bolts are of different diameters. The instructions tell how to determine which replacement bolts to use, but that is just the starting point. The bolts are left loose, then after measuring the new camber value, the wheel / spindle gets pushed or pulled to bring it into specs, THEN the nuts get tightened. I'll copy and format the drawings for you, but I'll have to post them later.

If you look at the heads of the bolts, they show the number "11" on them, then, if an adjusting bolt was installed, it will have one, two, or three dots next to that number.

Due to the steering and suspension geometric relationship of the parts, on most vehicles, when camber is changed, the attaching point of the steering linkage moves in or out as part of the spindle, so the steering linkage has to change length too to match that. That doesn't happen when the lower strut bolts are loose, so instead, when the spindle tips out, it is forced to turn too. On roughly 80 percent of vehicles, tipping the left wheel out on top causes that wheel to turn left too. This varies based, in part, on where the steering system is in relation to the tires. Most are behind, closer to the driver, but some are in front, closer to the bumper. Regardless, the point of this sad story is if camber has moved and now is incorrect, it caused the wheel to turn also. That turned wheel makes the car want to go that way. You have to counteract that by turning the steering wheel the other way. THAT is what makes the steering wheel off center when something is loose and / or shifted position.

These alignment angles change too due to lowered chassis ride height. That's an issue of sagged coil springs and time, not mileage. With sagged ride height, even if the numbers look good on the alignment computer, there will be poor tire wear because the geometry has changed for the moving parts. Tire wear will only be best when the car is standing still. It will be excessive and uneven as the car bounces up and down on the road.

This is more of an issue with the older, very strong "short arm / long arm" suspension system. Those used a lower control arm / ball joint, an upper control arm / ball joint, spindle, and frame rail to form a parallelogram. The shape of that is what kept the tire flat on the road throughout varying road conditions. That relationship was lost when ride height wasn't correct. With strut suspension, the upper control arm isn't used, but the relationship of the other parts is still important. You will get less tire wear with struts if ride height has sagged, compared to other suspension systems, but it still plays a part in good tire wear.

Look at the heads of the two bolts for the number "11". Then look for the dots I mentioned. If there's one dot, they show that to the left of the number. If there's two dots, the second one will be at the 4 o'clock position. If there's three dots, the third one will be at the 2 o'clock position. Based on interpreting the instructions, the more dots, the thinner the bolt, and the more play there will be.

The idea is when a skinnier bolt is installed, it provides the means of adjusting camber by pushing or pulling on top of the tire. Once in position, the bolts must be tightened sufficiently to hold the spindle. The clamping force is the only thing preventing the adjustment from slipping over bumpy roads.

Camber has to be set to specs very precisely to get best tire wear and to prevent a pull to one side. With this type of adjustment method, the job can be exceedingly tedious and frustrating. We never hit it just right the first time. How long it takes to get it right depends on how picky the mechanic is and how many times he tweaks the adjustment.

As I tried to describe, tipping the spindle to adjust camber also moves the steering arm on the spindle, so the steering linkage must be adjusted too. That is always the last step in the alignment procedure. On your model, with rack and pinion steering, that adjustment for "toe" is the threaded connection where the outer tie rod end is screwed onto the inner tie rod end. Along with the same adjustment on the other side, those set the two front wheels parallel to each other and center the steering wheel.

At this point, since you have the wheel off already, I would pull the spindle out about halfway toward you, then tighten the bolts. That should get camber reasonably close enough to allow you to drive to the alignment shop. The actual adjustment during the alignment is very tiny between "out of specs and "in specs"; almost too small to see by eye. That's why you'll only be able to get is somewhat close by yourself.