Qblue92

My '60 makes a low sound on the freeway. It sounds like the left side and I have been blaming the wheel bearing.
I took my axles out tonite to change out my rear end. Upon inspection, both wheel bearings look fine and turn smoothly with no noise. Can they look ok but be loud at speed? Should I change them anyway?? What else might make that noise in the left rear area??

59BlueSilver

I think it's the rear end. Did it make that sound after you put in the rear end you have now?

Qblue92

It started maybe last Fall, but I've had that rear end in there for 2 years or so.

DansYellow66

My experience with wheel bearings has been they howl mostly on corners. But since some cars have tapered roller axle bearings and some have ball bearings I'm not sure if that is always universal. Is it constant at speed or does it vary when you apply the throttle or back off the throttle and coast?

GTOguy

If the bearings turn smoothly and have no rough spots or excessive play, you can rule them out. It takes a pretty rough bearing to make noise. Also, bearings tend to growl when bad, not whine. Gears tend to whine.

Frankie the Fink

This is going to sound ridiculous to you but if you have a radio car...unscrew the antenna and take a ride and see if the sound goes away...

Qblue92

I think it varies when I'm accelerating or decelerating or coasting.

GTOguy

Sounds like possible ring and pinion noise. Does it go away at 'coast' or 'float'?

Qblue92

I put a different rear end in it. It has the same gear whine accelerating or just maintaining speed. If I let off the gas and coast, it stops. Did I put another bad rear end in with similar ring n pinion whine??

59BlueSilver

Brian,
Take your car to Transmission Doctor in Kennedale. David knows transmissions & rear ends. Let him ride with you and he can probably tell you what it is. I highly recommend him.

DansYellow66

I went through differential hell with a Plymouth last year - pulling and replacing the differential 4 times and two new R&P sets - still makes some noise. If you can turn the whine off and on and vary it by accelerating, feathering the throttle to hold steady speed and decelerating - then odds are very high it's still the differential.

Not sure what the deal is but the aftermarket seems to forgotten how to machine differential gears.

GTOguy

If I remember correctly, whine on acceleration is the pinion gear seated in too far, and whine on de-cel is the pinion gear seated too far out from the ring gear. The fact that it goes away on coast is a classic indicator of a pinion gear that is too tight. This may or not be your trouble, though.

Frankie the Fink

I guess post #6 fell on deaf ears (* SIGH *)
What are the odds a completely different rear end is making the identical noise ?

DansYellow66

In the case of my Plymouth and the gears and mechanic I used - they seem to be better than might be suspected. I'm hoping on my Plymouth that the old Coker tires are still contributing to my road noise - but probably not.

Qblue92

I can try that, but I'd like to know how it might be related. It has the stock radio system that I never use.

AZDoug

FTF is saying you may be getting wind noise from the antennae. It has nothing to do with the radio.

Doug

GTOguy

Sometimes transmission noise is telegraphed up and down the driveshaft and it can sound like a rear end and vise-versa. Try running the car in another gear and see if it does it. If it does it in every gear, you are back to the rear end. They make automotive stethoscopes, some are electric, for pin-pointing noises while driving. That may be your next course of action.

Pilot Dan

We had an old 62 Caddy back in the day that did this. We were convinced it must be a bad rear, got another from the local yard put it all back together and same problem. So, just for the heck of it we went back and got both axle shafts from that car and swapped them out. Problem gone!
The old axle bearings as I recall felt OK but apparently had enough play
to generate that whirring sound.

Westlotorn

I grew tired of chasing noises like this and having trouble pin pointing the exact cause.
Now I will put the car up on jack stands, good quality Jack Stands rated much higher than the car weight. I think each stand is 5,000 pound rated.

Then with help I have them run the car in gear at 45-55 MPH on the Jack Stands.
The car must be at least 2 inches off the ground as tires will expand as the RPM goes up and you don't want them to touch ground as you do this test.

Now go under the car on a creeper with a mechanics stethoscope and search all the bearings till you find the odd one.
I have been able to diagnose the exact bearing several times doing this.

Can it be dangerous, of course. With some thought it can be done safely.

I have used this to chase a noise in my wife's X5 BMW that eluded me for a while.
Ended up being a tight wheel bearing, zero play in it but it made noise. Driving the car it sounded like it was Center or pass side of the car. Testing found it was the Drivers side.

Diagnosed a carrier bearing in our Suburban a while back this way and found it was the drivers side carrier bearing.
It really helps to know exactly what is failing when you do a repair.

DansYellow66

I did this last year with my Plymouth trying to confirm noise in my rear end. I made sure I had the car secure on jackstands and pointed towards an open area where it couldn't immediately hit anything if something, somehow went wrong. Of course with a Corvette you have to prop up the trailing arms to keep the half shafts running at a reasonable angle and avoid u-joint interference.

Some of what I learned includes that this probably works a lot better on bearing noise than it does differential noise. Actually, it may allow you to eliminate bearings as a cause of noise which pretty much leaves the differential or the transmission. I noted, as GTOguy said above, that noise was transmitted up and down the driveshaft which made it difficult to pinpoint as differential or transmission noise. But I was able to determine that my wheel bearings were much quieter than my differential.

Another problem is that most differential noise often occurs on acceleration or deceleration - both of which are a little hard to duplicate up on jackstands with the wheels spinning free and no load on the drivetrain. But again, if the car is relatively quiet, then wheel bearings can be eliminated which leaves the rear end as the culprit.