View Full Version : '76 Fleetwood clanking... sometimes

03-17-06, 02:10 PM
About two weeks ago, I started noticing a pretty loud metallic clanking. I've spent several hours trying to find it without any luck.

The car rarely clanks when it's in Park. When I shift into anything else, it starts almost immediately, but quiets down or stops if I shift back into park. It usually goes away when I have the accelerator pressed, but if I let off enough it will start back up, regardless of how fast the car is going or what gear it is. I checked the exhaust pipes and crossover: all the mounts look fine and I didn't notice anything they could be hitting. The car still runs and shifts great, and all the engine and transmission mounts look good, too. When the engine warms up and the idle drops, sometimes it gets quieter or even goes away altogether.

I put a new carb on about three weeks ago, but I don't see how that could affect it since the throttle linkage and fuel lines are all in the same place. I haven't dropped any tools that I know of, and the noise is loud enough that I doubt it's anything small.

If anyone can think of anything else it might be, I'm out of ideas, and it's starting to get pretty obnoxious. Thanks in advance for any suggestions!

- Joe

03-17-06, 03:03 PM
Intriguing. Where does it sound like it's coming from? Underhood, underbody, rear end, does it matter whether the car is moving? Based on what I've read so far, I'm going to suggest checking out the torque converter and the propeller shaft, possibly the rear differential if it sounds like it's coming from back there, but from your post it doesn't sound like it. Good luck!


03-17-06, 03:16 PM
My 76 Delta 88 Royale did some clanking when driving.

Does it do it in harder turns or does it quiet down then? It is related to suspension travel?

Mine was, it was the sway bar bushings and end links getting very sloppy.
And eventually upper control arm bushings.

On my 80 T/A with 70 455, I did have the bendix break and the starter gear was bouncing off the flywheel under decel and sometimes during idle. Replaced starter and all was fine. But that one was tough to find. Very random noise. But under decel, was always there, and under accel, was never there.

03-17-06, 05:15 PM
It sounds like it's coming from the general vicinity around the transmission. It's hard to pinpoint exactly where it's coming from. I never would have guessed that the starter could cause it, but I'll probably start there - I think mine is pretty old. Is there a way to check the gear without actually replacing the starter?

The torque converter is on my list of things that are getting replaced this summer when I pull the engine. I would imagine that if it were the problem, the noise would be constant, but I won't discount the possibility.

The speed of the car doesn't affect the noise - it will do it during cruising as long as I'm only pressing the gas very lightly or not as all. Going around turns doesn't affect it at all.

Do these cars have a mechanical shift linkage? If they do, I'll take a look at that, too. I guess if it got bent or knocked out of alignment, it could bump something.

Thanks for the quick replies and advice!

- Joe

03-17-06, 05:29 PM
I have had a problem with a clanking sound from a car, not a cadillac but a car with a auto transmission, it sounded like if it was a engine bearing that gone bad but nothing else indicated that it was a bad bearing in the engine. It turn out to be the bolts that attached the converter to the flex disc that had loosend and did the clanking noise, so i just had to tighten the bolts and the sound dissapered.

good luck

/ jolle