Sound of a bad U-Joint?

[Ken Cunningham]

I have been chasing a metal-on-metal sound for about 4 months now.

The sound varies with wheel speed, not engine speed, and sounds like right side to me. That's why I have changed my passenger side rear wheel bearing. No help. Changed my front rotors and pads. No help. Inspected the rear brake drums and shoes when I pulled the axle, no evidence of problems on the axle wear surface, the drums or the shoes.

My passenger (wife) hears the sound as right underneath her, instead of clearly right side. I'm now wondering if a u joint could be going. They're not that old. I put heavy duty Spicer zerkless u joints in about 2 years ago.

The sound is like a "whish-whish-whish" varying (like I said) with wheel speed approx. 1x per wheel revolution. Applying the brakes does not stop the sound (like most brake noises would), just slows it down as the car slows. I would think that the u joints are spinning much faster than the wheels, but what do I know?

Thanks for any tips...

 

[Ken Cunningham]

BTW:

To diagnose this I tried putting the rear up on jackstands and started the car. I gingerly reached my foot in to step on the brake, them put the car into drive. I release the parking brake and then the foot brake.

The wheels start spinning, but I don't hear any unusual noise. I don't have a death wish, so I didn't lay down underneath the car. The wheels with no resistance start spinning faster, faster, faster.

Soon the wheels are moving like 60mph (I shoulda checked the speedo!) and I'm freaking. Step back on the brake and eventually stop the wheels.

Maybe if I could load the rear axle instead of hanging down it would make a difference, but I don't know if I'm supposed to support the car by the axle tubes???? I sure don't trust a floor jack or stands underneath the pumpkin while the wheels are spinning like a banshee.

 

[Red Regal T]

I have a sound like that. When I back out of my garage, I can hear it whish-whish whish.

At first, I thought it was the U-joint. Problem is, I can stop the car, right in the middle of the sound and the whish sound will continue in a single tone. In my case, it's something to do with the transmission. It's still shifting OK, but doing some odd things. I think it's ready to do something bad.

 

[Momar]

I also have this sound. I dont know what it is. I have checked, and the rear u joint is tight, but the front has a little play so I think I am going to try replacing it. It sounds like wheel bearings on mine, but havent got a chance to diagnose real closely. I have had it pop a couple of times recently when I first take off right after I put it in gear. I am really hoping it is just a u joint. I dont see how the rear end could pop like that, and I really dont want to have to mess w/ the tranny, but I guess I will have to deal with whatever it is.

Ben

 

[tom h]

Originally posted by Ken Cunningham
... Maybe if I could load the rear axle instead of hanging down it would make a difference,...

Maybe see if a cooperative smog test station would put your car on their "dyno"?

 

[scottyb]

I would not suspect the u-joints for 2 reasons:

1. Typically when they go bad, they just get loose and clink when changing gear directions.

2. For every wheel revolution, they turn 3.42 times so you whould hear the sound 3 times+ per wheel rev.

Next time you jack it up , put the car in 1st gear for your spin test to limit speed.