I have been having a strange popping noise in the right rear of my 99le. I replaced the rear struts a few months ago but this started a few weeks ago. When I'm approaching a stop and apply the brake, the popping sound happens. It doesn't happen every time, but frequently. I have also noticed it when I step out of the car. I can't replicate it by pushing on the bumper or moving the car by hand in any other way. I visually inspected that area and everything seems intact. Any advice?

 

Is the noise in sync with the tire RPM?

If the noise also occurs when getting out of the car perhaps the chassis is moving, could be suspension related.

Typical issues for rear suspension noise are worn sway bar bushing, sway bar links and upper strut support mounts.

You can check for upper strut mount noise (typically a knocking noise) by having someone listen to the back deck area while the car is being driven. The other parts are located under the chassis.

These noise typically occur when going over bumps not braking.

Another cause can be a broken strut spring which does happen and can make a pop.

Of course might also be the brake system, the shoes moving around or sticking. You can remove the drum for inspection.

Go over bumpy road and speed bumps to check for suspension noise issues. Inspect the spring, etc.

 

No, the noise doesn't seem to be in sync with the tire RPM that I can tell. The noise has occurred when I go over a bump, but rarely. It only consistently happens when braking. The strut and chassis assembly looked intact when I changed the struts recently, but I'll check. I'm suspicious that it is in the brake system, but that's the only consistent cause. How can I tell if the shoes are moving or sticking once I get the drum off? Is there something in particular I should look for?

Thanks a lot of the response.

 

Given the noise is not in sync with tire/brake drum RPM would suggest the problem is outside the brake system. Applying the brake may put strain on the suspension causing something to move. This could also be why the noise has occurred when going over bumps.

It happens that the bushings on the end of the suspension link rods and arm start to fail allowing excess movement of the knuckle the axle bolts to.

The strut spring has rubber insulators mounted on each side to deaden metal to metal contact noise. Make sure the upper and lower insulators are not allowing metal to metal contact.

Might also remove the drum and take a look however issues with shoes, warped drum, etc typically cause the noise to be in sync with drum/tire rotation.