1960s Clunking in front end

[David Greenburg]

My '60 has a sharp "clunk" that appears when hitting uneven pavement or on rough (or less than "pretty smooth") roads.  It's more evident at low speeds, probably because there's less ambient noise. And when coming to a complete stop at low speeds, like at a neighborhood stop sign, there is also a "clunk" or slight jolt. My mechanical guru, a pro who works only on pre-'79 domestic cars, and is quite familiar with Cadillacs of this era says there's nothing wrong; its just an old car; possibly a body mount is tired.  Nothing looks amiss visually in the front end, and when I had the front wheels off the ground and grabbed the tires there is no play. Car still has the original ball joints (riveted in) and shows 75k, although I have no proof that is original mileage.  Thoughts? 

[Cadman-iac]

  David,

 I would have a look at the tops of your shock absorbers. I've had a couple where the upper shell breaks the weld and it rattles on rough roads.
 It can't come off, but it bangs around on the shaft and against the lower shell.
  Also check the core support bushings between the frame and support. Not sure if there's one on each side or just one in the center on a '60.
 The frame can flex a little, and it's usually forward of the firewall. The body has so many mounting points that you don't get much from that portion, but the entirety of the front sheet metal rests on just the one or two bushings under the core support, and they take a beating on rough roads.
 Another possibility is if you keep any tools stashed under the hood for convenience. I do this and I've had some rattles sometimes from them, a pair of pliers, a screwdriver, or whatever.
 If you're sure that the front suspension is in good condition, I don't know what else it might be.
 Good luck with locating the noise.

 Rick

[Lexi]

Tools hidden can cause weird sounds. For years Lexi made an odd thunk noise when turning a corner, depending on speed. When working on the trunk pull down motor, I removed the trunk's panel cards and saw some tools stashed there that a previous owner had placed between the liner card and the passenger fender. Problem solved after they were removed. On another day I dropped a thumbwheel ratchet while working in the engine bay and I couldn't find it. I forgot that one of Murphy's Laws states that when something is dropped in a shop or related enviroment, things fall at right angles so I looked everywhere. Nope, not to be found. On a long shot I figured the tool had to have found it's way into the car's frame and was hiding there. If that is where it was, it would roll around when on the road and drive me nuts. So I put a bore scope down into the frame and there it was, 2 - 3 feet away. A long reach pick up tool was able to extract it. 2 hours wasted of time that I will never get back. So yes, lost, stashed or even stored tools could be a culprit if Rick's other suggestions don't pan out. Clay/Lexi

[David Greenburg]

Those are some good points. Shocks are good. That was shop's initial diagnosis and I did put new shocks on, and I'm now personally acquainted with the shock mounts and all is good. Tools are certainly a possibility. Years ago I found several things, including an old school remote starter button in the netheregions of my '59. Something stuck under a control arm would certainly explain it. I did drop a socket inside one of the coils doing the shocks, but I was able to extract it.

[Clewisiii]

Do you have the splash shield cover under the radiator. That could hold a lot. But would be more a rattle then a clunk.

I would assume more of an upper control arm issue. With weight of vehicle on ground it would move around. But once you Jack the car up and try to wiggle things the spring tension would hold it down tight. So you could not notice then.

[David Greenburg]

Carl:

You're right that there could be control issues that won't show up with the wheel off the ground. But I figured I'd try it in case it revealed something like a bad bearing. I do have an appointment at another shop for a second opinion.

[Steve W]

My car is a '68, so I don't know if it's the same issue, but my car made a similar noise. It was impossible to find by myself, so I had someone in the driver's seat while I was under the hood, and as the car was idling, I just had them take it from N to D...to P to R...and we found it. It was one of the upper control arms. The bearing was sliding in and out of the mounting on the arm... just enough to make a "clunk". Had to replace the upper control arm.

[David Greenburg]

Steve:

I'll try and get someone to help me check that. Front suspension was basically the same as yours. Sounds can be deceptive from the drivers seat, but it sounds like it's coming from the front passenger side.

[59-in-pieces]

David,

Maybe, it's that "lose nut" behind the steering wheel.

Sorry, I couldn't resist.

Have fun,
Steve B.

[David Greenburg]

Steve:

Nah, I'm pretty tight these days. I even torqued my neck.

[Clewisiii]

The good one from Rare Parts is on the right. This is after I pressed it out. The bad one from A Resto Parts is on the left. I believe the rare parts one was a repackaged Moog part.


The bad one would just fall right out.



Just for fun. I like pictures.

[Clewisiii]

Moog K426    But you should double check if it is right for you.

[Clewisiii]

While you at it you should have a look at the bump stops. Not sure if they are the same on 60. They are only $20 each from Moog on Amazon.

[David Greenburg]

Thanks, Carl.  I'll have to look up the Moog numbers. This weekend I rain into someone whose late father was somewhat of a hoarder of parts for his old Cadillacs, mostly 59-60.  Random stuff, but a lot of Moog boxes, so maybe I'll get lucky.