Strange Moan at stop/starts

[thomas91169]

i just noticed this the other day. its very random and i cant pin it down.

when coming to a stop, when im just about to fully stop, youll hear this moan coming from the rear, like something is locking up. then when you take off, it moans again, but after you get moving a few feet it goes away.

my hunches were
1)wheel bearings
2)frozen calipers
3)rear end

so i jacked up the car. there was no in and out, side to side or up and down play in the wheels at all. only play was the backlash in the tranny. since the wheels moved freely, that pretty much ruled out frozen calipers.

now on to the rear end. so i find a desolate road(which luckily for me, is next to a 1 mile brick wall, great for pinpointing noises), and just do non stop braking and taking off. nada. nothing. no noise at all. then i turn right to enter my neighborhood, and as im waiting at the stop, it does it. then it hits me. now that my rear end is differentiating power between the inner and outer rear, its whining. bingo.

wrongo. after taking off, i practice doing right stops and starts. nothing. then i go to do them left, and it does it again, but only once. all other left turns led to silence. then i try going back and forth between left and right stops, which led to more silence.

i then give up, and decide to wait till the issue becomes a problem and requires zero brainwork to fix.



anyone have any ideas? itd be awesome if it was my diff, since its at 85k and i was planning on doing 3.90's and a rebuild before summer, and this would just give me a better excuse.

 

[tomustang]

I know i use to forget to release the park-brake and it made a moaning sound at starting, then went away with speed. I could never tell it was still up and kept wondering wtf was that noice (starting and stopping) I finally parked after 20min of driving and wanted to pull the bake up and it was up already, haha

maybe one of your e-brake's is locked in, would be my first guess, not sure though but it might help

 

[DocG]

Have you checked for a bound and gagged body in the trunk?

 

[thomas91169]

maybe one of your e-brake's is locked in, would be my first guess, not sure though but it might help

yeah. i thought that it could possibly be that, due to the side exhaust being a mere 2" from the cable, possibly heating them and expanding the cable. but then thats directly opposite of how the work(theyd have to be pulled on to engage the brakes, not pushed against from an expanding cable). nevertheless, i drove around for a while to get it all nice and heated up, drove into the garage and put the rear in the air. rear cables are pretty much cool to the touch, and wheels spin freely(well, as much as 100lbs of rotating mass of the wheels, diff and DS can spin with my scrawny ass muscles).

tomorrow im gonna drain and refill the rear end.

 

[sjrtx]

yeah. i thought that it could possibly be that, due to the side exhaust being a mere 2" from the cable, possibly heating them and expanding the cable. but then thats directly opposite of how the work(theyd have to be pulled on to engage the brakes, not pushed against from an expanding cable). nevertheless, i drove around for a while to get it all nice and heated up, drove into the garage and put the rear in the air. rear cables are pretty much cool to the touch, and wheels spin freely(well, as much as 100lbs of rotating mass of the wheels, diff and DS can spin with my scrawny ass muscles).

tomorrow im gonna drain and refill the rear end.

Draining and refilling the rear is going to be expensive just to locate a sound....

Might want to have someone get in it and move it forward while standing next to it and try to pinpoint it. Or get it back up in the air and turn everything see if you can replicate it then.

 

[hognutz]

I would check you floating pins on the brake calipers. I am fighting my passenger rear right now. one of them was froze up a couple months ago and now it is starting to make noise again.

 

[thomas91169]

Floating Pins? looks like ima be getting a chiltons soon........

and i did more experimenting with the noise. i found its only when im turning left and driving very slow(as in, clutch out, no throttle, just barely idling by). i was in a culdesac just driving in left circles listening. it would NOT do it going clockwise(right) only c-cwise(left). and its coming from the drivers rear.

if i took off from a stop with the wheel straight ahead, no noise
if i took off from a stop with the wheel slightly to the right, no noise.
if i took off from a stop with the wheel slightly left, it makes the noise till youre moving a little bit(3ish mph).

 

[DTNODYA]

Take the driver-rear tire off and just do a visual inspection to see if anything looks odd. Then examine the rotor and pads ... I dunno