Frame Flex ?!?

[Beadhead]

My MM makes a loud "crunching" sound from the rear chassis when turning into a curbed drive. My dealer's head technician says the noise is due to the flexing of the frame. Seems the box frames on our MM's have an internal brace in the rear. On mine, one end of the brace is welded to the box wall, and the other end is an unwelded flange. The tech put two bolts, one per side, through the frame where the frame kicks over the rear axle. This reduced the noise (it used to occur even under light acceleration!) but didn't elimiate it. Has anyone else experienced this problem, or is this a one-off defect?

[Petrograde]

Yup,.. I get it too,. on occation. I thought it was the control arms sliding on the bearings.

Where exactly is this rear internal brace? I'll have to take a look at it next time I have her in jack stands.

[merc406]

One side's welded and the other's not, you better crawl under or whatever to see what is going on something is amiss.

[Beadhead]

Yup,.. I get it too,. on occation. I thought it was the control arms sliding on the bearings.

Where exactly is this rear internal brace? I'll have to take a look at it next time I have her in jack stands.

Evidently, the brace is inside the box frame just before the frame kicks up over the rear axle. There is a small window in the face of the box frame near the brace, which I think is how the technician diagnosed the problem. As for telling if you have the same problem, the tech said he isloated the location by noting the noise ocurred when the car was hoisted at that location. Maybe you could try jacking yours at that point and see if it makes the sound you are hearing.

[Beadhead]

One side's welded and the other's not, you better crawl under or whatever to see what is going on something is amiss.

I've examined the chassis and suspension components with the tech while the car was on the hoist, and there don't seem to be any other issues -- everything else is tight and properly aligned, including the body mounts.
Since the problem is within the box frame, it looks like the brace was improperly welded before the frame was welded up. Another case of poor quality control? If so, ther could be others out there just like it.

[Petrograde]

Evidently, the brace is inside the box frame just before the frame kicks up over the rear axle. There is a small window in the face of the box frame near the brace, which I think is how the technician diagnosed the problem. As for telling if you have the same problem, the tech said he isloated the location by noting the noise ocurred when the car was hoisted at that location. Maybe you could try jacking yours at that point and see if it makes the sound you are hearing.

That is the location I normally jack my car from,.. never heard any creaks or crunches. The noise only occurs during driving.

I'll prob'ly have her on jackstands next weekend, I'll take a look at the area near the brace just in case.

Thanks for the info! :up:

[Marauder8]

Ford's motto.........Quality is #1

[Kennyrauder]

I had the same problem & my Ford store fixed it pronto. The frame to body bolts were misaligned causing the bolts to rub against the frame holes. You can call my service writer here in Timmins Ontario Canada. 705-268-3673. Mike Torrens or email atmiketorrens@autonorth.com Best of luck, Kennyrauder.

[chasrein01]

I had a "noise" like that too. But I traced mine to the spare tire being slightly loose and bouncing going over the gutter rises during right turns only. I tightened the hold down and haven't heard another sound from there in months!

[ckadiddle]

I get a fairly loud noise from the passenger side rear when hitting certain driveways at a certain angle. Guess I need to check my spare tire first, then crawl underneath and check that frame stuff. I haven't worried about it up to this point because the 97 and 01 Crown Vics I owned before the Marauder both made some occaisional klunks and klanks from the front and rear.

[jgc61sr2002]

I could be the steering stops. When the steering wheel is turned all the way in one direction and you go up an incline that can cause a squeek or scraping sound.

[cougarmandan]

I have that noise too. I thought about the spare, but I haven't checked it yet. I had the spare out 2 months ago and I started noticing it a few weeks ago. It only happens when I am making a sharp right turn into my drive. I have a little dip in the drive and at first I thought I was scaping something. I've been meaning to get under there and check but, man, its too cold and I can't remember to check it when its convienient. I have an oil change coming up at the end of the month, I will check it out then when I have it on the lift.