Loud noise troubleshoot, frame is cracked!?

[fords2fast4u]

So i recently bought my 93 cobra and I've been using it as a daily driver and there are a few issues.

I've done some things like replaced the door locks (was getting stuck in my car!) and replaced the drive shaft with the 5k mile old aluminum one out of my 1994...

although the new DS did stop the shaking and loud noise coming from the front U-joint, the car still has a very loud popping noise coming from under the car when taking off with the wheels turned (either way) at very low speeds.

In parking lots and when turning corners at less than 5 mph, the car sounds like its falling apart. It won't do it all the time, but when it does, it sounds like the u-joint or DS is hitting something. No show of wear on the old DS from making contact with anything...

When replacing the DS, i looked at the joints/bushings and noticed a crack in the steel where the upper control arm mounts to the car. there's a piece of L shaped steel that goes from one subframe to the other over the rear end. Right by one of the factory drain wholes is a crack. It looks like its been spot welded once, but broke again. (SEE PICS).

the car does have subframe connectors and lower control arms. AND the rear quarter on the driver's side a stress crack in it new the rear quarter window apex. The torque boxes look fine, only visible problem is the crack in the metal under the car and the quater.

The deal with the cracks is just a start, but maybe you guys have an idea as to what is causing this noise?

 

[fords2fast4u]

two more... God I love this car. Can't wait to start on it... but for now i just need it 'right'.

 

[wildstang90]

My 90 LX was doing somehting like that when I pulled out. I went to replace all the bushings in the rear of the car and found that the uper passaanger control arm bushing was nere gone and the inner part of the arm was worn my poping was from the arm bouncing around what was left of the bushing. As for the cracks I have never seen it but I would take it in and have some one weld it back up. The best thing I ever did was replace the bushings in the rear it rides and launches so much better now.

 

[fords2fast4u]

so it was doing that when you pulled out of parking lots and side streets?

and you just replaced the 4 control arm bushings? I'll probably put in some uppers while I'm there just because. Could you see the wear/missing bushing piece while the arm was on?

and i can do that weld myself. No sense in having three different kinds of welders and paying someone else to do a job on my own ride!

anyone else got any ideas?

 

[86bluecobra]

I had a crack in my floor pan. I just welded it up and subframed the car. Stiffened it up and have never seen anymore issues.

 

[wildstang90]

I knew the bushings would be worn just from the age of the car. I had no idea that the bushings were making the knock in the back. If you put your car on stands I used the bumper mounts then I lifted up the axle about 4 inches with the stress off the control arms you can check your bushings all the stress of your hard launches are felt on the passanger side thats where I had about 3/4 of an inch of play in the bushings.

Yea when I pulled out easy I would hear it even if I was going slow and hit the breaks I would hear it.

 

[Darkwriter77]

Hmmmm ... I've been hearing a noise kind of like that in Frankenstang's '89 notch for a couple of years, now. I thought it was just the lower control arm bushings, since the torque boxes didn't have any visible damage, but I never thought to look up above there. Thanks for the pics! I'll have to crawl under there and see if maybe the same thing is happening there as what you've got.