Be aware the vehicle needs to be aligned when replacing struts. With this very common front strut design, one of the main adjustments is done at the lower of the two strut mounting holes. On Chrysler products, those lower holes are elongated to allow for that adjustment. With GM original struts, those holes must be ground out to allow the adjustments to be made. Some aftermarket replacements come with the holes already elongated. When they are not, your alignment specialist will have to disassemble them to do that procedure. When you install the new struts yourself, there may be an extra charge to take them apart again. If you grind the holes yourself, I recommend you wear disposable gloves due the miserable metal filings that will get stuck in your skin. Be sure to wear eye protection too.
I wouldn't be too concerned with the front lower bolts because even though you might tighten them properly, they're going to be loosened again during the alignment, then they must be tightened while the vehicle is sitting on the tires, with the alignment projectors attached. We have to reach behind the wheel and feel our way around to put the socket on the nuts. There's no way to do that with a torque wrench. It's the clamping forces developed with those bolts that hold the alignment from shifting when you hit bumps and pot holes, so we tighten them as much as possible by hand with a very long ratchet. I'm sure they get tightened much tighter than specs call for.
Chrysler uses "cam bolts" for the lower of the two bolts. Those have offset heads for a couple of reasons. First, "camber" can be adjusted to a perfect setting very easily by just rotating the bolt head. Second, that offset head sits in a pocket that holds the strut from shifting on bumpy roads, even when the nuts aren't tightened to specs. As GM vehicles come from the factory, once the hole is elongated, they rely strictly on the clamping forces of those two bolts to hold the strut in alignment. To ensure they don't slip, most conscientious alignment specialists will want to sell you a pair of aftermarket cam bolts, especially if they do the grinding on the lower holes. Those provide the same ease of adjustment and a much better holding power over the original bolts. There's a few different styles of these bolts. The most common is shown in the third photo. Without those, we have to loosen the two bolts, shove the wheel closer to where we want it, tighten the bolts, take a new series of readings on the alignment computer, loosen the bolts, shove the wheel, hope for the best, tighten the nuts, take another set of readings, and do that sometimes a dozen times before we decide it's "close enough" and move on. Besides both wheels being in specs for good tire wear, it's critical camber be the same on both front wheels to avoid a pull to one side. Setting one wheel is hard enough. Matching the second one to the first wheel gets to be real tedious and frustrating.
When you install the lower bolts, it is acceptable to put a very light coating of grease on the threads, but do not put any on the sides of the knuckle. That's where the clamping force has to hold it in adjustment. We don't want anything on there that would weaken that force. Absolutely do not use any type of anti-seize compound anywhere related to the struts or wheels. A coworker coated everything with that stuff, thinking he was doing me a favor, but after doing the alignment and trying to tighten those bolts a number of times, the adjustments kept slipping just from the weight of the car. Eventually out of frustration, I tightened those bolts so tight by hand that I actually snapped one by pulling it apart with a hand ratchet. Those bolts are 3/4" in diameter and I'm a little guy, but there was no friction whatsoever to stop me from doing that. That's when I took it apart and realized all the anti-seize compound was all over everything. Took another hour to clean that all off and replace the bolt.
Also be aware, due to the age of the car, expect the coil springs to be sagged. That lowers chassis ride height, and that causes bad tire wear and handling even when the alignment computer says every adjustment is perfect. Those readings only apply to a vehicle that is standing still. They don't account for the geometric changes the parts go through as the vehicle bounces up and down. Replacing struts by switching the old coil springs over to the new struts has a hge safety concern involved, and it takes more time. If you installed "quick struts", those that come preassembled with new springs, upper mounting plates, and hardware, you eliminated the safety problem and you eliminated the ride height problem. Regardless, most alignment mechanics will measure ride height first to ensure it is within specs. If it is not within specs, most will not do the alignment because they're taking your money without being able to deliver what you're paying for, that being good tire wear and good handling.
I posted the height specs for your model in the fourth drawing, but I was dismayed to find they didn't include the line drawing to show where those measurements are to be taken. Every tire and alignment shop has a small book that lists every model and where to take the readings. Chrysler has a somewhat complicated method but it takes into account different size tires. For most other models, they either just list one height spec, or they'll provide multiple values for all the different tire size options that were available.
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Saturday, March 18th, 2023 AT 2:39 PM
