Strange Grinding Noise

[Brad]

The other day I heard this grinding noise coming from the left rear. I got home and had a really good look all around for foreign objects but saw nothing. I gathered it was a stick and had fallen out. Now tonight I've been out and it's back. It's strange, it's only there when I'm either taking off hard, pushing the rear suspension down, or when cornering tightly left, taking load off. If I go around a right corner it's not there, or if I go though a fast left hander it's not there. The sound definetly sounds like a body rub and I can also feel it through the car. Any ideas?

[Craig]

Seized shock absorber?

[Brad]

Brand new Tein's???....

I've not felt any difference in the feel of ther car.

Inner or outer CV or bearing?

[Craig]

Hmmm how about a dodgy half/drive shaft or wheel bearing then?

[SuperMazdaKart]

suspension bushings maybe. was the cause of my rear squeak grinds. also in the rear left side.

had grease put over the bushings & the noise has gone away.

[JBT]

Inner or outer CV or bearing?

That would be my suspect. Are the CV rubber boots intact?

[Brad]

CV boot rubbers look fine and all lower inner bushes have been replaced. Outer lower and all upper are original.

[JBT]

Are the new bushes rubber or polywhatsit. Can the poly ones make a noise if the grease comes out or wasn't applied properly? Can you replicate the noise by bouncing the rear corner (I know.......they don't bounce much )

If the noise has started since the suspension work was done, then maybe that's the place to start looking.

[Brad]

Bushes are Polyeurothane. Yes, the noise started only on Sunday, but I did have a pretty big trackday on the weekend, hitting a few kerbs and the usual thrashing. I can't see how it would be bushes as the noise seems to also be relative to the torque applied to the wheel as opposed to the presure put on it laterally, and when the downward presure is lifted, as in turning left, it comes on more easily. I'm strongly leaning toward the bearing. It would make sense to be the left one as msot of the corners at the track I frequent are right hookers. The car's done 141,000kms BTW.

[JBT]

Could well be a rear bearing. My car's done 146,000km and is OK.........ATM.

The last track day might have screwed your wheel bearing but I just don't like coincidences. You should be able to check the bearing by jacking the rear and carefully listening for noises when turning the wheel or rocking it to check for play. Driving the car in an \"S\" pattern might highlight a dodgy bearing too. No noise turning left and lots turning right at constant speed could mean left bearing.

Edit/ 10:10am - just went for a little drive on the perfect test track for you Brad - Mt Coot-tha....smooth with lots of esses. Just thinking on my drive.............bearing noises are more growling/rumble than grinding.