Creaking strut tower?!!

[iTurbo]

I recently got my Shelby Lancer going again, and I have had this long term problem with a creaking/snapping sound emanating from the passenger side strut tower. At first I thought it was just a strut mount, but I've tried replacing that and no dice. In fact, I've replaced *everything* to do with the suspension (k-frame, arms, knuckles etc) and the noise remains. The addition of a strut tower bar did not change it either.

It happens mostly when doing low speed turns and the stress imparted on the strut tower seems to be flexing something. I can push/pull on the fender to make the car sway side-to-side and make the noise happen while the car is parked. If I place my hand on the strut tower just below the motor mount, I can REALLY feel the vibration/noise coming out from that small area. Is something cracked or broken? Can a frame shop fix it? It is SOOO annoying.

Years ago I got into a fender bender with the car, and had to replace the passenger side fender and strut (bent). The noise didn't start right away, but several months later started and has slowly been getting worse. I cannot tell by looking at it that anything is bent.

[looneytuner]

there is a little welded tab that the kframe mounts on.

[iTurbo]

I will look closely at that next time I'm under the car. It seemed fine when I reinstalled the K-frame ('91) a few weeks ago. The noise seems to be coming from a little bit above the K-frame mount, somewhere near the strut tower/frame rail connection.

[Mike M]

May or not be the cause, but some suggestions anyway:

If the car has much of any rust, the backside of the strut tower is attached to the top of the inner fender well can rust (as well as the entire wheel well really). I suppose this could potentially cause a noise if the metal in that area is weak enough. My Lancer Shelby is undergoing body/rust repair/paint and I have had my inner fender wells completely rebuilt as mine were starting to rust in that area as well as large holes in them! This thread has a nice pic of the inner fender rebuilt (further down), along the top of the new metal in the pic is where it meets the strut tower, and rust was creeping up in that area: http://www.turbo-mopar.com/forums/showthread.php?t=17508

On highly abused vehicles (circle track Shelby Charger) I have seen the frame rails start to separate from the body in the area you are talking about. Again, could cause noises if it is weak and flexing enough.

Never saw myself but a friend had a T-top Shelby Tona that the frame rails started cracking on (he assumed due to stress of having t-tops though).

Good luck!

[turbovanman²]

Is the floor rotted? does it have the spider cracks on the firewall?

Did you replace the whole strut bearing and are you sure you put it together correctly? I've seen them put together wrong and give noise.

[iTurbo]

Thanks for the replies/ideas. The car is almost entirely rust free. However, it has very high miles and has seen it's share of hard driving. I have the plastic inner fenders removed and it looks really good up inside there. The floors and firewall are rust free and I can't say I've seen any cracks anywhere. I have a hunch that the fender bender I was in probably cracked a joint or seam weld.

EDIT: yes, the strut mount was replaced along with the bearing. Like I said, I've replaced everything on the car when I rebuilt the chassis a couple years ago and the noise did not change one bit. I've had 3 different K-frame/arms/knuckles/racks assemblies on the car so it's definately not that.

[TopDollar69]

Could it be one of the welds on the motor mount bracket that's welded to the frame?

[iTurbo]

Actually, it may very well be. The noise is coming from right around that area or maybe a little below. I haven't driven the car much since I put it back together because the starter sounded so awful after sitting for the last year.

I don't know if it makes any difference, but the car has MP motor mount inserts on the passenger and front, a Polybushings.com rear semi-solid dogbone, and a stock replacement trans insert. From watching the car on the dyno, there is barely any engine movement.

[minigts]

Well I can tell you that I have a squeak/popping problem with my car that is coming from the strut tower. It's partially due to my coil-overs and camber plates as I had to modify the top for the plates to fit. Every bump I hit, it makes a popping sound that has driven me crazy for about 2 years. I don't know the best way to fix it other than welding some thicker metal under the bottom side and reinforcing it, but that takes some time and engineering, both of which I am lacking.

So I write back to say, it could be flex in the tower metal where everything mounts. Easy test is to have the hood up and push down on the front close to the strut to get some movement going on the tower. That may tell you exactly where it is.

[iTurbo]

Well I'm getting the car aligned today. Had to tell them to just ignore the noise as I'm almost positive it's the frame/strut tower. In addition to the creaking/cracking noise from the strut tower on turns/bumps, something in the front frame is also making a loud single low freq popping noise as I turn left and the weight of the car shifts. It's like something is buckling as the frame flexes.

Also, if I shimmy the front of the car back and forth while parked it will recreate the creaking noise. If I place the palm of my hand on the inner fender just below the motor mount near the belts I can feel a VERY intense vibration emanating from that area as the noise happens. Something inside the frame rail is broken for sure. I just hope I can find a frame/body shop that is willing to deal with it.

[minigts]

Well I'm getting the car aligned today. Had to tell them to just ignore the noise as I'm almost positive it's the frame/strut tower. In addition to the creaking/cracking noise from the strut tower on turns/bumps, something in the front frame is also making a loud single low freq popping noise as I turn left and the weight of the car shifts. It's like something is buckling as the frame flexes.

Also, if I shimmy the front of the car back and forth while parked it will recreate the creaking noise. If I place the palm of my hand on the inner fender just below the motor mount near the belts I can feel a VERY intense vibration emanating from that area as the noise happens. Something inside the frame rail is broken for sure. I just hope I can find a frame/body shop that is willing to deal with it.

Sounds exactly like my problem, only mine is at the strut tower only, not at the mounts (not that I'm aware of anyways!). I had to tell the alignment guy the same thing, ignore the noise. I wish I could record the sound because I guarantee it's the same noise you are hearing. Your description sounds identical to mine.

[iTurbo]

I could probably get a good video with my Cybershot if I can get my bro to help me. The passenger side motor mount looks fine; no obvious damage and no rust there. Engine torque output doesn't affect the noise, but turning the steering wheel sure does. If you are driving down the street ~10MPH and turn the steering wheel back and forth, it will creak/crack/snap as the weight of the car shifts side to side.

The car has poly bushings everwhere, Eibach springs, GR2 struts, GAJ shocks, reinforced subframes, PB.com rear bar, '91 front suspension, and strut tower bar. Other that that noise the car is pretty rigid and handles very nicely. I think I finally found the weak link though:evil:

[looneytuner]

May or not be the cause, but some suggestions anyway:

If the car has much of any rust, the backside of the strut tower is attached to the top of the inner fender well can rust (as well as the entire wheel well really). I suppose this could potentially cause a noise if the metal in that area is weak enough. My Lancer Shelby is undergoing body/rust repair/paint and I have had my inner fender wells completely rebuilt as mine were starting to rust in that area as well as large holes in them! This thread has a nice pic of the inner fender rebuilt (further down), along the top of the new metal in the pic is where it meets the strut tower, and rust was creeping up in that area: http://www.turbo-mopar.com/forums/showthread.php?t=17508

On highly abused vehicles (circle track Shelby Charger) I have seen the frame rails start to separate from the body in the area you are talking about. Again, could cause noises if it is weak and flexing enough.

Never saw myself but a friend had a T-top Shelby Tona that the frame rails started cracking on (he assumed due to stress of having t-tops though).

Good luck!

PLus 2! My silver 87 GTs had the right side rusting there. Today I looked at my blue one on the driver's side and it is rusted through. You cannot see this unless you pull the rear splash shield from the well, or shine a light down from the top after pulling the rubber strip that holds the cowl plastic down. Neither car has sealant on the top of this seam and the water sits because there should be a drain hole for the low pocket that holds water.

[iTurbo]

I don't know what happened, but suddenly the noise is gone! I haven't changed anything with the car, BUT, it has was raining yesterday....maybe something got wet. Wierd.

[looneytuner]

That sounds like sway bar bushings. If so, your buddy will be back again. At least it's not something serious.