My G- Marquis sinks on the front right side!

[El Duende]

After closley inspecting our recently purchased 2000 Grand Marquis, we noticed that it is lower on the front right side. Looking at it from the back, it appears to be leaning. The previous owner went up a curb and the bumper, passenger's side fender & headlight, and many steering components were replaced. The body and frame look straight, so we suspected it was the shocks needed replacement. Both in the front had blown and Gabriel "Ultra-somethings" (They were the top-of-the-line shocks available. I'll get the name soon.) took their place. Unfortunately, this didn't fix our problem. It's still falling forward, so we think it might be the control arms. Do the control arms on this year/model G- Marq affect ride height? Can they be adjusted through the two connections that mount onto the frame? I have photos of the upper arms for reference.

Here is the front right side, where the impact took place. As you can see, the two big nuts (No pun) on the "adjustment cams" (Going off of the Hayne's Manual here) have a gap between them. I read that these determine the caster of the respective wheel.


This is another shot of the same side.


This here is the front left side, which looks to be in place.

[johnunit]

Never heard of control arms bending on these things. They were made for bounding curbs in P71 Crown Vic form. The spring being broken or bent seems more likely.

That said, taking it for an alignment (at a competent shop) may help you figure out whether you have bent suspension parts, as they'd probably throw out the alignment. Some newer alignment machines will even tell the technician what parts are worn or damaged automatically.

[Brown_Muscle]

even though they are tough it is possible the control arm could be bent...also shocks do not affect ride height, they simply dampen road forces and keep the car from bouncing all around every time you hit a bump.

That said, taking it for an alignment (at a competent shop) may help you figure out whether you have bent suspension parts, as they'd probably throw out the alignment. Some newer alignment machines will even tell the technician what parts are worn or damaged automatically.

X2

[gadget73]

Weak spring is my bet. The upper control arm has no bearing on ride height anyway. Even if it were damaged, you'd most likely see stress cracks or at a minimum, cracking in the paint. It also wouldn't align properly if the arm had any real amount of bend to it. Ride height is almost entirely determined by the spring sandwiched between the frame and the lower control arm. Most likely the spring is weak, or the end of it snapped off at the very bottom. Its also possible that when the front end was put back together, the lower control arm mounting bolts were tightened when the suspension was not at normal ride height. If those are torqued with the suspension extended or compressed, it loads the rubber bushing and can make the car sit high or low.

[El Duende]

Ah... I see. You all brought up good points. We didn't even consider the springs. I forgot to mention that even after a 1,400 mile trip, the tires all wore out evenly. The ride is smooth, with no vibrations or tire shimmy and like I said, the frame looks straight. I'll get back at you guys after we take her to an alignment shop. I wonder if it really is that the shop reassembled everything on the passenger's side incorrectly and left the spring compressed. (As mentioned)

Thanks for the help. The more we can rule things out, the easier it'll be to take steps to fix it. I haven't driven her much in the state she's in because I'm waiting for the fix.

[El Duende]

Alright, well I took the GM to Brakes Plus...

And I told the worker everything listed in this thread. He whipped out a measuring tape and checked the height of the car on both sides. Hopefully his measurements were accurate, because it was parked on a sharp incline. Anyway, he recorded of a slightly less than 3 ft. on each side and told me that it was typical of these cars to be level at that height. We're going to replace the rear shocks this weekend and then measuring the height again on a flat surface. I'll take it for an alignment next week if it's not sagging anymore. You guys think the problem might've corrected itself by adding new front shocks? They were blown, big time.

[CheeseSteakJim]

If you really wanted to get investigating, you can pay a body shop to throw it up on their frame machine and measure some reference points to make sure the frame isn't bent. That'll probably cost a couple hundred, but it's something else you could eliminate.


Not that I personally think jumping a curb is going to bend a frame. I used to do it all the time with my F150.

[El Duende]

If you really wanted to get investigating, you can pay a body shop to throw it up on their frame machine and measure some reference points to make sure the frame isn't bent. That'll probably cost a couple hundred, but it's something else you could eliminate.


Not that I personally think jumping a curb is going to bend a frame. I used to do it all the time with my F150.

That'll be our last resort. If it does turn out bent, then it'll be on craigslist the next day...

[CheeseSteakJim]

having a frame bent back isn't really all that expensive. i would reconsider selling it solely for that reason, if it came to being such a thing.

[El Duende]

having a frame bent back isn't really all that expensive. i would reconsider selling it solely for that reason, if it came to being such a thing.

As long as the damage isn't too extensive, it will remain a daily in the meantime. The front bumper and passenger-side fender were replaced, but that could've been due to cosmetic reasons. Fingers crossed! I'll update you all after we get the rear shocks replaced and the car aligned.

[GM_Guy]

Springs could be bad. Did the previous owner have a very overweight passenger often?
One of the springs could also have turned. Feel around in the lower pocket for the end of the spring to be at the end of the groove. (groove for the bottom of the spring to sit in, you install the spring so the end of the spring is at the end of the groove. You'll see it if if you look up at the bottom of the control arm.

You can just make out the end of the spring "groove" in this pic where the end of the spring should be.

Alex.

[GM_Guy]

(guess theres no adding attachments in an edit).

[El Duende]

Springs could be bad. Did the previous owner have a very overweight passenger often?
One of the springs could also have turned. Feel around in the lower pocket for the end of the spring to be at the end of the groove. (groove for the bottom of the spring to sit in, you install the spring so the end of the spring is at the end of the groove. You'll see it if if you look up at the bottom of the control arm.

You can just make out the end of the spring "groove" in this pic where the end of the spring should be.

Alex.

Haha! It's quite ironic that we'd joked about the previous owner hauling a heavy passenger, thinking it couldn't possibly be the cause. I'll get back at you after I get under there.

Good looking out!

[GM_Guy]

Story: Car place I deal with regularily, we where talking springs, anyway, a really FAT guy owned a car that they 1)had to find extra heavy duty springs for one side of the car 2)load the car up with a few hundred pounds of ballast for an alignment (or have him sit in it if he stayed with the car) 3) The car would sit all cock eyed with nobody in the car (or with a regular mechanic) and drove like poop on a test drive due to the funky alignment without the ballast. =-)

Alex.

[gadget73]

Shocks have no real effect on ride height. thats entirely done with the springs, but the bushings being installed wierdly can have some affect on it as well. if the lower arm has not been removed, then you're almost certainly good with the bushings.