[HUMBLER]

I have one and cannot figure out what it is. It sounds like the gas tank is loose but it doesn't appear to be. A high pitch metal to metal sound. I've checked the exhaust, springs, shocks, inside trunk, license plate holder, etc. I thought I was on to something when I discovered the rocker trim was not seated in the lower portion of the clips on both sides of the car. I just got done reinserting those and thought for sure that was it. Nope, still have the rattle. I only hear it at low speeds over bumps and appears to be coming from the rear. Let me know if you have any thoughts!

[67drake]

I tried tracking down a high pitch squeal since I owned my car. After I replaced the rear control arm bushings while working on the suspension,the sound disappeared. Bonus! I had metal to metal contact between the arms and brackets.
Pics of what I had in this thread- http://psp.aquacomp.net/topic.asp?TO...Terms=,bushing

[West Coast GTO]

Open the trunk and look to both the left and right sides. There is a brace that is attached to the outer fender area that came loose on my car. I had a bodyshop re-attach using one of their bonding materials and no more rear end noise over bumps. Just grab the brace and see if it moves.

[HUMBLER]

Man, I would've never even seen that brace. I slid in a piece of rubber to the drivers side that was indeed loose. We'll see if that was it.

I looked at all the control arms and didn't see any evidence of rubbing but will jack it up and look again.

Thanks!

[67drake]

Originally Posted by HUMBLER

Man, I would've never even seen that brace. I slid in a piece of rubber to the drivers side that was indeed loose. We'll see if that was it.

I looked at all the control arms and didn't see any evidence of rubbing but will jack it up and look again.

Thanks!

Exactly. I never would have seen metal to metal with the car on the ground. Jacked up, I could see the shiny metal areas where there was contact.
I also had loose braces that WCGTO was talking about. I shoved a thin piece of rubber under mine just to see if that was making the squeal,and in my case it was not. Another good spot to check though.

[HUMBLER]

Well I went over the suspension with a flashlight and the car in the air, wheels off. Couldn't see any evidence of rubbin. Also I would think I would hear it just pushing the car up and down if it was the suspension, no?

I even took out the rear seat and package tray (needed replacing anyways!) and just can't find this rattle. It sounds like something loose by the way, it rattles, not a scraping sound.

Any other thoughts? I'm wondering if it is something on the top of the gas tank. Or, could it be something inside the muffler? Crazy...

[Sirrotica]

I've seen muffler baffles break loose and cause a rattle, jack the car up and take a rubber mallet and beat on the muffler. I've also used this method to jolt the suspension by hitting a tire to help you duplicate the sound while the car is in the air. Good luck........

[HUMBLER]

No on the mufflers and I've beaten on everything under there. The sound is coming from just above the right rear tire which I thought for sure it was going to be that brace but it seems solid as it could be.

[goatless]

You may want to check the trunk lid itself. There is an insulating material between the bracing and skin that can dry up and fall out with age, thus allowing the skin to rattle on the bracing.

[HUMBLER]

All of the bracing appears to be welded in place, no insulation. Maybe I'm not following you though as to where that insulation is?

Those two rods that run from hinge to hinge, could those be loose when the lid is closed? Or, do they have tension both open and closed?

[goatless]

The trunk spring rods are under tension when the trunk is closed.
The "insulation" I mentioned is little "dollups" of some kind of adhesive located at strategic points of the bracing on the bottom of the trunk lid. The skin is not welded to the bracing. You can check it by gently pushing down in a few spots. Some of the adhesive has fallen out in spots on my '69 and I'm pretty sure that's where I'm getting an intermittent rattle.

[HUMBLER]

I'll check it out...

[2002Z4CSS]

Can you have someone drive the car over bumps while you are riding in the trunk to help isolate the area of the noise?

[HUMBLER]

I do need to do that, yes.

[PLAY400]

Originally Posted by goatless

You may want to check the trunk lid itself. There is an insulating material between the bracing and skin that can dry up and fall out with age, thus allowing the skin to rattle on the bracing.

The inner skin is glued to the outer skin at every contact point to prevent it from rattling. Gave my lid a tweek to adjust it last year and broke most of them loose. Took a while to find the rattle. Hold the lid up and bang the edge with the heal of your hand to hear if it rattles

[Sirrotica]

I have also had a trunk torsion rod come off the hook when someone put a stack of tires in the trunk and one slid forward and unhooked the torsion bar and it rattled enough to drive you crazy. Just something else to check.

[HUMBLER]

Trunk lid / bracing all seems solid and the rods are as they should be. I'll jump in the trunk and go for a ride as soon as the weather clears back up and give an update. On the plus side, ordered a couple new interior parts today!

[2002Z4CSS]

Originally Posted by HUMBLER

Trunk lid / bracing all seems solid and the rods are as they should be. I'll jump in the trunk and go for a ride as soon as the weather clears back up and give an update. On the plus side, ordered a couple new interior parts today!

There is an electronic tool called a Chassis Ear that most Ford and Lincoln dealers have as a required tool. Maybe you know someone who works in one of these dealers that can loan you the tool to help isolate the cause of the rattle.

[rcorrigan5]

Is the gas tank pad between the tank and the underside of the trunk floor? If the pad is not there, that might be cause for the noise.

Randy C.