The Stovebolt Site Forums The Shop Area Engine Shop Rear Axle "Klunk" Can U Help?

My beautiful '54 Coupe has developed a nasty 'klunk' sound emanating from the rear passenger wheel when cornering (left) at low speeds. Occasionally, the driver's side rear axle will clunk as well when making a right turn. I looked up rear axle noise in my 1956 copy of "Fix Your Chevrolet." They use the term 'klunking noise' saying that the problem is with the "axle shaft spacer." But the 'klunk' I'm hearing seems to come from the wheel well itself - not the pumpkin. Can anybody further enlighten me on this one? Where does one come up with an axle shaft spacer and is this likely to solve the problem I have described? Oh, I should say that, yes, I have checked. The lug nuts are tight and the hub cap doesn't have any rocks in it! I can feel very little end play in either wheel.

Jack up the rear and try to pull the wheel toward you and then push it in towards the center of the car. See if you can duplicate the noise. Axle shaft spacers were avialable in differnt widths. I don't know where you will find them today.
Cleon

Revted,

The axle shaft spacer, or thrust block doesn't do much that could contribute to your noises in my book. Because it happens on both left and right turns it hints that it's associated with the spider gears, or that it making that noise when it loaded more than it is when going straight.

My first unprofessional guess would be that pesky u-joint in back of the tranny. If it is loose and starting to fail, it might be binding and sending a quick 'snap' down the drivetrain and out the axle.

Maybe the nice pretty hubcaps are acting like a drumhead and magnifying the sound as it travels down the axle.

There isn't much that goes wrong with the rear ends in those cars but the u-joint is famous for flying apart.

My crystal ball is in the shop at the moment so this is just a wild guess. Let us know what happens!

Stuart

I'm with Stuart on this one. Check the U-joints and if there is any play at all, you might get lucky and get by with a cheap fix. Good luck.

Check the leaf spring bushings,
Scott

When was the last time you greased the rear axle "clamps" - those "clamps" the encircle the rear axle on top of the spring. Remember, with the up and down motion of the axle, it rotates in the "clamps". If they become dry, they can "pop" at times. I wouldn't even mention it, but it happened to me. As I looked closely, I found grease zerks on those "clamps". A little grease fixed my "clunking" noise. I hope this helps you out!
Joe

Ok, been a bit busy, and will be out of town for the next 10 days - but I have appreciated all your suggestions and have checked things out as best I can. Here's what I've got so far - I can find no zerk fittings on the axle mounts, spring shackles seem tight, the u-joint appears to be tight with no unexpected play - but when I jack up the rear end, push in and out on the right rear wheel as hard as I can I do get a bit of a 'klunk.' Automarc, Stuart mentioned a "snap" and come to think of it, that is a good description of the sound - especially if being transmitted from somewhere up the line. But Stuart, I can't seem to locate a problem in the u-joint. Maybe I'm missing something? What about those spider gears - what to look for there? Is this one of those things that I should just keep driving it till the problem presents itself? But at 65 on the freeway, I'm a little nervous about it. Thanks again for your help. As mentioned I will be out of town for the next 10 days or so. Ted