2002 Saturn Vue 02 Odd Question

Assuming nothing is bent, it's "ride height" you need to check. That is determined by the springs. At this age it is real common to find them sagged. With "short arm / long arm (SLA)" suspension systems incorrect ride height will cause greatly accelerated tire wear even when the numbers on the alignment computer are perfect because the geometry of the suspension system will be wrong and the wheels will go through the wrong movements as the vehicle goes up and down. You have a strut front suspension which is more tolerant of incorrect ride height but it will still adversely affect handling and braking.

Besides the uneven ride height which you already noticed, an alignment mechanic will want to correct it if it's low. The first step is to determine how low it is. Every alignment shop will have a small book that shows every car model, where to take the measurements, and what they should be. Some measure between two different points on a suspension part, typically the lower control arm. That requires no allowances to be made for different size tires. Most just want you to measure from the ground to a certain point. Those are based on the original tire size. With a tire that's 1/2" shorter in diameter, that will lower the axle 1/4" so the correct ride height measurement will be 1/4" lower than specified.

Nope. Strictly the springs. That is what sets the ride height. The springs are ON the struts but the struts only hold the wheel straight up and down and reduce their tendency to bounce. (It's a giant shock absorber). Where some people get confused is most shock absorbers and struts are gas-charged. That makes the shaft extend by itself when they're unpackaged. That gas charge is there to prevent the oil from foaming and becoming aerated which would reduce their effectiveness. You can push the shaft back down by hand so it's easy to see that won't support much of the vehicle's weight.

Even a bent control arm won't cause a change in ride height unless it is so severely bent that the bottom of the wheel is folded under the car. The car is supported through the tire, wheel, spindle, strut body to the spring, spring, upper strut mount, to the body. The only variable is the spring. The lower control arm and ball joint holds the bottom of the wheel from moving forward, backward, or to the side. It isn't involved in anything up and down.

Now that I've ruled out the strut, while that is not a variable, it is possible for the spring plate to rust out but the vehicle would be sitting a lot lower than one inch too low. You'd feel the banging as you tried to drive it. I've only seen that happen on Fords and old Hondas. You can also look for a broken coil spring but to drop just an inch it would have to be broken near the bottom. That is easiest to find by feeling and running your fingers around it but be careful because a break will result in one end being pointed and sharp.

OH! Sorry, I thought we were talking about the gap on top which more commonly is the issue. A difference in the gap at the back is not uncommon but it shouldn't be so much that it causes a problem. A bent lower control arm COULD cause that. It is made from rolled-up plate steel. The damage can be hard to identify but you can start by looking for signs of cracked paint or a small spot of rust in just one area. The bent anti-sway bar link you mentioned is another clue.

Also look at the cross member the control arm is bolted to. If that is mounted with large bolts, it could slide back from a hard impact. That will move the ball joint back and tighten that gap. An alignment will show that too. "Caster" is the measurement in question. All that is critical is it must be nearly the same on both sides. That is extremely important on rear-wheel-drive cars. With front-wheel-drive it has almost no affect on pulling to one side but it is still a good indicator of a bent part.

A typical caster reading is around 3.0 degrees. Due to production tolerances a difference of half a degree is nothing to worry about. To move the lower ball joint back an inch would change caster quite a bit and that would be evident on the alignment computer. The reading would be lower; closer to 0.0 degrees or even a negative number.

Caster is the rearward tilt of the two steering pivots as viewed from the side of the car. In this case those are the upper strut mount and the lower ball joint. The mount should be more to the rear of the vehicle, similar to the rake of the fork on a motorcycle or bicycle.