[Mike87Coupe]

Hi everyone,

I think I posted about this a long time ago and I finally just got around to starting my diagnosis. Basically, I heard some noises a while back and instead of guessing and fixing something that wasn't broken, I figured I'd wait until it broke so I was certain. I think something is now on the verge of breaking and I need help with the diagnosis. It's an automatic 1987 C4 coupe with 95,000 miles.

It started with a squeak in the back left wheel. The squeak seemed to get faster as the wheel moved faster. The squeak sounded like a metal friction squeak. As time went on, the squeak got louder and louder. The other day, I'm driving and I hear almost a bang under the car and then a loud grinding noise that seemed to come and go. Fortunately I was only a mile from home and slowly got it back. The grinding at some points almost sounded like something was hanging off the car and dragging on the ground. I got home and looked and nothing was hanging off the car. The noise happened when I was driving straight but got really loud around my last slow uphill right turn into the driveway from a stop.

Today, I got the jack under the rear differential and got the wheels off the ground. I released the parking brake and shifted to neutral. I slowly turned the wheel by hand and I hear the squeak in one particular spot. Also, as I hear the squeak, I hear a rather loud click sound that I don't hear on the other wheel. The sound seems to be coming from the wheel side of the half shaft.

I'm thinking universal on the half shaft or a wheel bearing. Based on my description, does anyone have any ideas or things I can try to narrow in on the possible problem?

Thanks!
Mike

[Seabee 86]

This sounds fairly simple. I would jack the car up and visually inspect all rotational components that are located near the drivers side rear wheel. My first thought, given the "scraping" noise you described, is a wheel bearing. However u-joints are a common (for lack of a better word) failure point with these cars.

Let us know what you find.

[mat helm]

Brake pads, or lack there of. If so, sounds like you've destroyed your rotor at this point too...

[mat helm]

btw, It's been my experience that u joints tend to make a clicking sound when their wore out....

[Slicktop]

Originally Posted by mat helm

Brake pads, or lack there of. If so, sounds like you've destroyed your rotor at this point too...

Maybe, but he said nothing about the noise occuring when the brakes were applied, only that it gets louder as the wheel spins faster. When a brake pad starts to go, the wear indicator makes noise when you apply the brakes, not when you are just driving....

Anyway, it is easy to check the pads, rotors, wheel bearings and u joints, so the OP needs to either do that or have it done by a shop.

[1979carl]

Emergency brake hardware ? Happened on my 79, return spring broke and was trapped between shoe and rotor. Made a horrible sound.

[Mike87Coupe]

Thanks for the replies. Nope, definitely not the pads, I can guarantee that. Rotors are fine too.

Now, the last post brought something to my memory. Lately my parking brake feels like it's not doing anything. I had the intention of adjusting it, but haven't done it yet. About 2 months ago, just to test the parking brake, I pulled it at 5 mph. It make a heck of a noise. I haven't really played with it since. I don't like using the automatic as a kick stand with no parking brake, but I figured it could wait.

That said, I'm not sure it's related to this issue, although it certainly could be. Doesn't the parking brake squeeze the passenger side rear wheel and not the driver's? I'm having issue with the driver's side.

[Mike87Coupe]

Also, the parts are easy to check, I'm sure... However, I'm not sure how to check or what to look for.

Thanks,
Mike

[mat helm]

I believe the 87 has a internal drum type parking brake. Using the inside of the rotor as a drum I think. So exchange the words "Pads & Rotor" to "Shoes & Drum...../rotor".....

At any rate, I think the rotor needs to come off before you'll know what you're dealing with...

[Slicktop]

Originally Posted by Mike87Coupe

Thanks for the replies. Nope, definitely not the pads, I can guarantee that. Rotors are fine too.

Now, the last post brought something to my memory. Lately my parking brake feels like it's not doing anything. I had the intention of adjusting it, but haven't done it yet. About 2 months ago, just to test the parking brake, I pulled it at 5 mph. It make a heck of a noise. I haven't really played with it since. I don't like using the automatic as a kick stand with no parking brake, but I figured it could wait.

That said, I'm not sure it's related to this issue, although it certainly could be. Doesn't the parking brake squeeze the passenger side rear wheel and not the driver's? I'm having issue with the driver's side.

There are parking brake shoes on each side in the rear.