vistablue mustang

OK I have been having break problems for the last 4 months now and yesterday while I was washing the car I wanted to back the car up, well I left the drivers door open and had my foot on the break when I moved the car from Park to Reverse I heard this grinding noise and it kept doing it whenever I would move from gear to gear (Auto Tranny). The grinding noise is coming from the rear on the drivers side. Took it to the dealer it did it when I was parking the car, service manager comes out to hear it and it would not do it . It's there now but I have a feeling that they will tell me they could not find anything wrong again. Any ideas? Could it be related to the break vibration I have been having?

ryan1112

I'm a little confused from what you are saying. Is the sound coming from the transmission when you shift from park to reverse or when you back up and hit the brakes? You mentioned at the beginning of the post that it is a brake problem.
Also, have someone else put the car in gear while you get down and put your head closer to the ground so you can tell exactly where the sound is coming from.

vistablue mustang

I still have this issue so I figured I would bump it back up, I am positive it is not a break related issue and more then likely a transmission issue. When the car is stationary and you shift from Park to drive or reverse you can hear a grinding noise come from the rear. This only seems to happen on the first start up after the car has sat for a while, or in the morning. My foot is on the break and no mater how hard I depress the pedal there is a grinding noise that comes from the rear behine the wheels and under the car. The best way to hear it is if you leave your driver door open and put the car into gear. Oh this is with an Auto Tranny. Any thoughts?

Rash

Did you ever find out what this was? I had the exact same thing happen to me this morning.

StangMahn

check your tranny fluid, or just replace it, you may have some binding in the gears, possibly some metal shavings or something.

kevinb120

It would help to know what kind of 'grinding' noise it is, is it like a groaning noise or like bare metal chewing something up?

Centurion96

I never understood the problem description from the OP. So Rash, is this sound only coming when the car is moving or when you put the tranny in gear while standing still? If standing still it will probably be the tranny. Unless Ford has had some major insite on building auto trannys since the E4OD the bottom pan will need to be dropped to change the fluid properly (as in no drain plug). Check and replace the tranny filter as well as the fluid. Now if this noise is coming from the rear and not from under the seat I would suspect brakes (not breaks). Two things may cause grinding, a stuck caliper, which will start showing grooves cutting into the rotor, or stuck e-brake shoes. Again unless Ford had a dramatic break thru since my wife's Grand Marquis was built, the e-brake is a pair of mini brake shoes inside a mini drum portion of the rear rotors. Unfortunately they cannot be inspected until you pull the wheels and rotors. If you can put the car on a lift that would be great. Jack stands will do if the rear end is off the ground and the front wheels are chocked to keep it from rolling, with the e-brake off rotate the rear wheels and listen for grinding. You should be able to isolate the problem.

BB
Semper Fi

kevinb120

I'm thinking its the normal creak/groan you hear when a 'rested' suspension gets flexed again for the first time???

Rash

It didn't happen today (thank god), and it only happened that once so far. It sounded like a metallic scrapping or rubbing, and maybe had a cyclical quality to it which was faster than the tires were rotating - that's why I don't think it was the brakes or wheels. Since it happened only for a couple seconds, it's hard to pinpoint any more details. If it happens again, now that i'm listenong for it, i'm sure i'll be able to give a better description.

kevinb120

facinating

06GT4RAD

Bob the rear brake do NOT have these drum type parking brake design any more. It is all controlled by the caliper and rotor. The rear calipers are a pretty weird design internally they actually screw in and out when the parking brake is applied and released applying pressure to the rotor.

As for the OP problem This sound like it may be a brake issue or a internal Rear end noise. It is hard enough trying to diagnose noises in person half the time let alone over the internet. Also what one person calls a grinding noise another might call it a scraping noise.

I recall seeing something not sure if it was this site or the other but there is an issue with a part inside the bell housing if I recall that is rubbing on something. Let me see if I can locate it.

Well I cannot locate the thread i had in mind.

Richard

kevinb120

well some help you are Richard

vistablue mustang

Wow, my post returned from the abyss, I believe the noise I was talking about was what Kevin mentioned about the suspension flexing, but it would do this sometimes even if the car had not sat for any period of time. I no longer have my 06 but I only heard the noise when the car was not moving, Never when I was driving.