Okay, WHAT could be rattling under my car?

[Mr_Q]

I have had the car up on ramps, on a lift, searched and felt all underneath, had people jumping up and down on the car from the inside and I absolutely cannot see/hear where this rattle is coming from!

I lowered my car with the HnR Coilovers and ever since then--I have a rattle from the passenger rear that does not seem to related to the actually suspension hardware.

What I mean by that is--the rattle happens--when there is rear end vibration or ressonation. The suspension can do it's full travel up and down without rattle. It can get fully compressed and expand at various speeds and there is NO RATTLE.

But drive down a cobbled, pitted road where you get lots of quick, sharp, SUBTLE movements in the suspension and you get...."clunk...clunk-clunk...clunk-clunk-clunk".

Only sharp, small bumps seem to make it rattle. It sounds like it's right around where the fuel tank is or further back.

Anyone have any idea what might be in the way with the car 1" lower up front and 1.5" lower in back?

Thanks.

 

[iskwezm]

Mine had rattle. looked for weeks for it, it turned out it was the exhaust(modified),rt side tail pipe that would only rattle when driving on certan roads.

 

[McQueens Dream]

we had the same problem you have, even before we lowered ours, the dealer never actually found the problem, but they retightened everything to spec, made sure the suspension was not the issue and sent it on it's way. our front end also had the same clunk in it, and that was the engine cradle was not torqued down to spec, so they realigned all the stuff they needed to, torqued the cradle down and sent it on it's way. now, it's been 2 months, the car still makes the same noises it always did. we have the 100K warranty, so i am not worried about it no more, if it gets worse, we will worry about it. mainly i chalk it up to being a Mustang, it's not a Mercedes, and it don't cost a Mercedes price...they make noises, it can't be helped...

 

[gaberubin]

sounds very much like an exhaust rattle—check distance of your pipes to frame/other objects and that all exhaust hangers are tight...

 

[StonePony]

sounds like a loose nut behind the wheel....

 

[kooldawg6]

Jenns05Stang had a rattle that she located and corrected at the back of her car.

Here is the link to that thread...
http://forums.stangnet.com/showthread.php?t=662084

 

[Mr_Q]

That Jenn thread is a good one. But I don't think that's it. Mainly because this noise started *after* I did the coil overs. :\

But thanks!

 

[Jenns01TA]

Mr. Q. check all RH panhard bar, lateral stiffener bar and RH exhaust isolator bracket bolts for spec TQ. You have a new panhard bar, exhaust + suspension. Although this is occurring after the H&R install, it does not immediatley point to the suspension itself. 90% says yes - probably an illfated bolt rattling.

PM me your email if you would like me to send you the PDF exploded views of the rear suspension and exhaust on the GT. It will help when you wiggle under her with the TQ wrench.

All are easy enough self-checks before you drag her back to a dealer or shop.

~J~

 

[Mr_Q]

I just checked under again with ramps. The rear brakes likes do run through the rear control arms and do make noise if I flick at them and let them hit the arm. But it's not anywhere near loud enough.

I also checked my trunk pistons. They are solid and tight. Maybe Ford redesigned them for '07?

Anyway, I press on. The panhard bar seems tight. The spherical bearing on the one end isn't hitting anything.

I wonder if the springs themselves might be leaping out of their perch enough to rattle? [yikes?]

 

[Mr_Q]

Okay I have definitely isolated the noise to only when one tire is up and the other is not, etc. The see-saw effect. It seems to make a more real THUD when the wheel on the passenger side drops too.

I also noticed some pretty gnarly scratches where the panhard bar connects on the passenger side. It's the side with the spherical ball joint.

Could it be "popping" against or rattling if not adjusted correctly? It feels solid as heck but obviosuly I can't do much when it's on ramps. We jumped up and down and it was quiet.

I wonder if only the see-saw road deflections will reveal it though.

 

[mustangmike6996]

ford has a TSB about a rattle caused by exhaust on these cars, luckily i have not experienced it (knock on wood)

 

[05MGT]

Check all your heat shields and bushings.

 

[bigcat]

do you have inserts for the rod end to take up the extra space? or is it just the rod end? can you take a pic of the scratches? i just installed an adj. panhard with rod ends on both ends, so i am familiar with that area you are talking about.

 

[66_stang]

It's your over-axle pipe hitting that stupid metal bar right below it. Make sure you got everything on tight and you should be set.

 

[MBDiagMan]

You will not find the answer to this question on an enthusiast forum. The ONLY way to find the source of the rattle is to safely raise the car and get underneath. You will then have to pry, prod, push, pull and bang on everything in that area until you find it.

There is no shortcut here. You will have to get dirty if you want to fix it.

Good luck.

 

[Mr_Q]

well ive gotten as dirty as I can with what tools I have in the garage. (ramps only for lift)

Guess a trip to the shop is in order.

Oh and it's not the exhaust. Long ago ruled that one out. Thanks though.

 

[Hoboattacker]

Did you get new LCA's when you did your lowering kit? I've heard about some rattling if you leave the stock one's on after you lower these cars.

 

[Mr_Q]

Nope, I did get the panhard bar....that's something to think about I guess. At least an excuse to pull it all apart again, heh.

 

[Hoboattacker]

I can't find the article or thread where I read it, but I remember reading something about how when you lower your car it changes the angle of the LCA's and that it would be a good idea to get new LCA's when you decide to lower your car. Just something to think about, I guess.