p0ny

Hello everyone,

I have a 2011 GT 5.0. I'm having a problem with a single clunk/knock sound which seems to be coming from the rear end (both sides). Most noticeable when going up a driveway at an angle. No problems on flat surfaces. I'm the second owner. The first owner dropped the vehicle 1.5" all the way around. Installed Eibach Sportline springs and swaybar but kept the factory shocks and struts. I've had it to numerous shops up on lifts and the clunk cannot be duplicated while on the lift (frustrating). Opinions are all over the place - you need new shocks and struts, you don't need new shocks and struts, etc, etc, etc.

Brandon302

May be the shocks, or the rear endlinks, do you know if the stock endlinks are on the car with the new sway?

radioguy1

Ford dealer should be able to diagnose that. They certainly see enough Mustangs with suspension issues???? Obvious first step is to look underneath for any thing loose like exhaust.

Ltngdrvr

Driveline slack maybe.

Brandon302

Could be the over axle pipes, could always hit them and see if they make a clunk inside the car.

p0ny

Not sure. When up in the air everything is tight and looks great.

p0ny

Ford thought the shocks were too long and should be shorter. I mentioned that the old owner installed Eibach Sportline Springs and did not replace the factory shocks and struts. The exhaust has a loose clamp which was tightened but still hearing the clunk sound.

p0ny

will the vehicle flex when going at an angle up a driveway?

Brandon302

Guess it's possible, if the stock end links were on the sway they may be at an angle and not perpendicular like they are from the factory. I had a similar sound once I lowered my car. Only happened at low speeds over speed bumps, or over into a driveway. Ended up going away, I did pack the bushings with grease though so that may have helped resolve it.

Brandon302

Does it sound similar to this?

p0ny

No, it's not a squeek. It's definitely a clunk. That's a good idea. Will see if I can make an audio of it.

radioguy1

I think I would get the dealer's suspension expert and take him for a ride with you. Usually once they hear it, while in the car, they can narrow down the cause.

Mrsuitcase

I know nothing about suspensions or mechanics; but.... here's a simple one to rule out.

... since you're a new owner, is everything in your spare tire compartment secured?

p0ny

Yes.

Brandon302

Also if you get under the car, shouldn't need to jack it up, and hit parts of the rear suspension with your palm and see if you can track down the noise. That is how I traced the noise on my car to the endlinks. And you can drive with the back seats down to hear the noise more clearly.

p0ny

no way to get under the car as it sits too low. Bringing it to yet another shop today and we'll see what they have to say. Thanks

FordService

Hi p0ny,

I see you have a couple of mods, but I’d like to get this escalated for you. This way your dealer and the customer service manager can work together to find where this noise is coming from. Please make an appointment and PM me with your VIN, dealer, mileage, full name, and best daytime number. Please remember, this may or may not be a customer pay repair.

Deysha

p0ny

Hi Deysha, do you have a phone number I can reach you? if so would you mind PM me?

Thanks

Glenn

stock shocks work for the stock springs, once you take them out of their useable range they tend not to work so well. I had that problem with a lowered car and when I replaced the stock struts and shocks it solved the problem.

lets say the stock shocks have a working range of 2.5 inches and when you drop it with lowering springs you take away some of the usable 2.5 inches. you might end up with 1 inch of usable shock and then after that you have nothing.

p0ny

If it were the shocks wouldn't I notice this clunk/knock on bumpy roads as well because I don't. Drives great all other times.