Need help diagnosing grinding sound - intermittent


#1

Hi all,



Got an intermittent grinding sound on the 85 Olds Cutlass, RWD. Definitely coming from the driver side, but still unsure which wheel.



It’s tough to tell what causes the sound, it seems to usually show up after a good drive of 30-40 minutes, and can only be heard at low speeds. It used to be, when the grinding sound would show up, there would be a slight pause between each grinding sound, which would increase or decrease with the vehicle speed. Applying the brakes doesn’t seem to alter the sound at all.



I jacked up the front driver side and tried to shake the wheel/tire but couldn’t feel any definite give. Took the wheel off and when I turned the rotor by hand, I could hear a slight grind every time it reached a point, but I don’t see anything making contact. The pads have plenty of life left on them, the warning metal tabs are far from the rotor. I didn’t take the caliper off, but if I do, what can I look for? Could this be a bad wheel bearing? Anything on the rear drums to check?



Thanks…this sound is kinda disturbing but I’d really like to fix it myself.

Jad


#2

Sounds like you’ve done most of teh diagnostic work for us, you were right close to solving the problem, and backed off. Yeah, this sounds like a bearing. Pull the caliper up and rotate the disc. If you still hear that grinding, you’ll need to pull the bearings.

I recommend new bearings. They’re not expensive, and frankly to properly inspect bearings involves thorough cleaning in a solvent, close inspection under a good light, and frankly…it just ain’t worth it.


#3

Thanks for the reply mountainbike! Sounds like a plan, I’ll pull the caliper off and try that out…I wish the bearings came in a complete assembly for this car, it looks like you have to replace inner and outer bearings and seals individually…

If the sound goes away with the caliper off I guess it’s a caliper/pad problem, maybe an adjustment thing? I guess I could remove and reinstall the pads if that’s the case.

I’ll post back with the results. Thanks for all your informative posts, mountainbike…I put you up there with ok4450, dartman, tester, and joseph meehan.


#4

If you have complicated wheel covers; try driving with them off and see what happens. Check the lug nuts. Sometimes they get loose and make grinding noises. I read the other posts so I won’t just repeat them.


#5

Are wheel bearings like brakes, change them in pairs? Or can I just do the one side if it’s the only one complaining?


#6

Thanks. I take that as a high compliment.