these noise just started a few days ago . its a knocking noise in the rear of the car , Varies with speed (you speed up it gets faster knock ) . Only does it when your off the gas . if you give it any gas it goes away ? Also the noise gets slighy louder when i lightly press the brakes , but will go away if i give it decent brake pressure when stoping .

What could this be ? I have not jacked it up yet i will tomrrow at work hopefully .

I just within 2-3 months did my rear brakes also .

p.s. ebrake doenst work since i did rear brakes i think .

Thanks any help would be great .

 

Not sure about the "knocking," but mine is making a whining noise. I need to re-set backlash on the rear-end. I'm not sure what the brakes are all about on your car. but with my car, there's no noise whenever I'm on the gas, and then when I let off it's like a ****ing geardrive being next to my head.

I'd put money on that or your pinion bearing. Maybe U-joints, but how many miles on the car?

 

** CHECK YOUR U-JOINTS ASAP!!!**

if those are ok, put the car on jack stands and run it, if the noise is from the rear end, pull the cover and look for missing teeth on the gears

 

car has 78,000 miles rear end has been servise twice i think in its life and it has a slight input seal drive shaft leak it sprays gearlube over my underside.

no whinning at all in my rear end fluid has always been good and not black . ..

i have not checked the level in a while , but i have not been driving it alot ?

ill pull into my shop tommrow maybe into a underground pit and have a look . hope its not drive train related iam on my 3rd tranny already ..

 

iam thinking maybe u-joints , i sure dont know without waiting till tommrow ill let you all know

 

i pulled it into my shop today . only in a oil change bay . i dint get a chance to get it in the air , we where busy . and what i sall was not much . the u joints dont feel loose but the car is on the ground so i cant very see for sure . but i have a fluid leak for sure in the rear diff where the driveshaft and diff meet . only loose little GL-5 . topped it off .

I think its my brakes , something to do with the e-brake , i just atteppt to use my ebrake for the first time after i did my own rear brakes and i think around the time this noise started . whould this cause that noise . also i forgot a shim on one side of the brake pads on the left rear too .

 

yeah sounds like your gonna have to trial test the car making this sound in the air to narrow it down... jack it up and have a friend work the pedals while you listen (be careful and use extra stands please if your gonna be under your car while its running and wheels are spinning...

you can simply pinch the brake lines with your figures to engage one brake whilst letting the other wheel continue to turn. hope that helps you narrow down the location. but other than that... you got me.

 

I just bought a 1993 Z28. It makes the EXACT sound you describe. Like a tapping/knocking from the rear. I hear it coming to a stop, or leaving at light throttle. If I put the trans in neutral it goes away immidiately. Driving slow, holding the brakes a little lets me hear the sound quite well. I rolled the window down and I don't think I hear it outside as much. It is much louder in the car.
At first I thought it was a U-joint. I checked the U-joint and it was a little stiff so I replaced it. The sound is still there. Let me know if you find anything.

 

well i did a big NO NO i . i guess since i was tired from replacing all rotors and pads . i forgot to torque down my left rear rim . and started to get loose and the rotor was moving around makeing a knocking noise . glad i was not driving it alot . now i know torque them dam lug nuts down !

 

Good thing you caught that, it could have been a disasterous mishap.

 

So you had a loose rear wheel? Did that fix it?

I did that when doing a spring-over conversion on my Jeep. I got to watch a 35" mud tires roll past me on a side street, and smash into a parked truck in someones driveway. I thank god that it dod not happen at a decent speed.

I'll check my lugs today. Thanks!

 

yes that fixed the noise now noise no more . every one check you nuts

 

Good lesson for all, take your time and double check - especially the lug nuts!

 

My car still makes the noise. I was not that lucky. I am thinking it might be a bad pinion bearing or something.