Another Problem

[Whatarush]

I am getting so frustrated with this car. Gone mysteriously is the issue where the car wont start without first locking/unlocking it but now there is a scary popping noise coming from the rear end. It started last weekend and only shows itself when the car is warmed up and when I am breaking (slowing down/stopping) and occasionally when taking off from a stop. I have replaced the differential fluid to what the manual specifies thinking that might be the problem but the noise remains. Any ideas of what this noise might be?

[ne0fiend]

I guess I'll be the first to admit it; I have no idea what this could be.
To my knowledge there is nothing that could cause a popping noise from the rear end.
Maybe your idea of popping and mine are completely different?
Any chance of you posting a sound clip?

[derbs]

Popping noise????? Never heard of that before. When the rear end went out in my 94 z it was a growling,grinding. If it was me check and make sure everything in your rear suspension is still together. Check your cradle bushings and your rear swaybar endlinks just in case. Since you hear the noise when you stop and take off. This could be just as easy as your exhaust if it sounds more like a rattle??? Wouldn't know till I hear it.

[ne0fiend]

Popping noise????? Never heard of that before. When the rear end went out in my 94 z it was a growling,grinding. If it was me check and make sure everything in your rear suspension is still together. Check your cradle bushings and your rear swaybar endlinks just in case. Since you hear the noise when you stop and take off. This could be just as easy as your exhaust if it sounds more like a rattle??? Wouldn't know till I hear it.

Good call, Derbs. Maybe something is juggling around down there...
I'd lift the car and take a pry-bar to the suspension components.

[racer426]

u joints can make a pop noise

[mark21742]

I'll guess cradle slap from wornout bushings...the thing beats against the floor and can make a hell of a loud poping and banging noise

[cammed goat]

I was thinking cradle bushings as well. If not the U-joint.

[Whatarush]

I have gone under the car and looked for anything that appeared to be worn or missing (such as a bolt etc) but did not see anything with the naked eye that would indicate anything was wrong. Just out of curiosity how would I test a U joint to see if it is bad?

[Whatarush]

I guess I'll be the first to admit it; I have no idea what this could be.
To my knowledge there is nothing that could cause a popping noise from the rear end.
Maybe your idea of popping and mine are completely different?
Any chance of you posting a sound clip?

I dont have a sound clip but the closest thing i can think of that sounds like the noise I am hearing is....If you had a baseball rolling around in the trunk and when you slammed on the brakes it hit the wall of your trunk and made a thud/popping noise, that is the noise I hear but it is a little more higher pitched. Originally I actually thought something might be in the trunk or in the spare tire area which I already check but nothing.

[derbs]

I've seen a couple pictures of the arms of the cradle that actually have cracked. and they have said about the same thing your going through. Also check you tranny mount. Unless you do a shit load of burnouts and launch at 6500rpms I would not think the u-joints would be bad... I've been running stockers with a 4k stall and haven't ran into this but anything could happen.

[0rion]

I'd guess craddle bushings, u-joint, or it could even be the vent solenoid. I've heard those pop back there but they're usually not "baseball bat" loud. U-joint will usually be more of a "ping" and bushings will sound more like something is slapping the bottom of the car.

[ne0fiend]

C-Bushing get my vote also.
Check the struts too.

[cammed goat]

Have you checked your brakes to see if the calipers aren't seizing?

[Whatarush]

I checked all the bushings, bolts, pinion, yoke, brakes etc. and did not find anything wrong. It is now in the hands of the mechanic. I will update if anything is found.

My guess is there is something wrong in the differential.

[0rion]

my bushings looked fine too but they were in fact bad....I'm still going with bushings if it sounds like someone hitting the floorboard.

[ne0fiend]

my bushings looked fine too but they were in fact bad....I'm still going with bushings if it sounds like someone hitting the floorboard.

Agreed.
The only way to really be sure is to pry on them; move them around. A spot-check wouldn't reveal any issues, outside of obvious visible damage.

[pmolina0436]

I have the same issue on mine..like it sounds like your a thump or something..I only here it on stops and when I start taking off but i have to go really slow to notice it...They first said it might have been my shocks..but got them replaced and still same sound..I also thought it might be the bushings...but got the full bushing kit and still same sound..It hasnt gotten worse but still bothers me..so let me know what ur tool man has to say about it..

[ne0fiend]

I have the same issue on mine..like it sounds like your a thump or something..I only here it on stops and when I start taking off but i have to go really slow to notice it...They first said it might have been my shocks..but got them replaced and still same sound..I also thought it might be the bushings...but got the full bushing kit and still same sound..It hasnt gotten worse but still bothers me..so let me know what ur tool man has to say about it..

Motor, Transmission mount IMO.

[pmolina0436]

Motor, Transmission mount IMO.

i dont know...im thinking the motor mounts so thate my next fix..i dont its that..but lets see what happens

[cammed goat]

What about the carrier bushing that mounts to the diff cover? Checked that at all?