I've got a vibration/noise on my '68 El Camino that only occurs on left hand turns. Goes away once I straighten out or if I turn right. Does not take much of a cornering force to cause the noise to start.

What it is not:

Replaced rear axles and bearings (right rear needed it anyways).
Replaced/repacked/readjusted front wheel bearings (mismatched parts).
Swapped steering gearbox (faster ratio).

So far I have gone through likely candidates finding additional other issues justifying part replacement. Ideas what it might be before I wind up swapping parts that truly don't need it?

Thanks,
Steve

re check your front wheel bearings!

Uhhh... ok.

I think I have done that, the bearings themselves are now new, and I thought everything looked fine. So what might I be looking for in particular?

If you're sure your bearings are ok, you might want to look at engine and transmission mounts. Does it make any of that noise when you accelerate?

is it possible for your steering linkage to be hitting something when you make that left turn?
david

Steve, I'm going to guess steering gear. Try swapping out the old one (no other canges) and see what happens. I see this a lot on rack and pinion cars but I have had an occasional gear box do the same thing. Does it get more difficult to steer to that direction as well?

Ok engine mounts are new, transmission mount looked fine (very recently did engine swap), and it does not take much of a turn to induce the noise. It can start with nothing more than a crowned road.

I used to notice it only on sharper corners with the original steering box and the effort is, well, effortless on both types of cornering.

My own suspicions lean towards bushings on one of the rear converging links. I can make a case for a side load induced metal to metal contact point conducting lots of interesting noises. I just have not gotten a chance to make a close inspection to tell if I can see/detect anything conclusive. I had hoped to tap some A-body specific experience that I don't have (but seem to be getting). But if nothing else, if I keep driving it as is, eventually the culprit will make itself evident. I think I have covered the things that could become catastrophically evident at least...

You know I think I have probably not put more than 500 miles on this "car" since I got last June in between reworking the interior for most of the summer and the engine for a couple of months this winter. I am finally getting to where I almost trust it to reliably get both there *and* back, not that it has ever stranded me. Just getting used to an experienced vehicle again :-)

My own suspicions lean towards bushings on one of the rear converging links. I can make a case for a side load induced metal to metal contact point conducting lots of interesting noises. I just have not gotten a chance to make a close inspection to tell if I can see/detect anything conclusive.
Bring it by Steve....we can fix that. :D



Take a close look at the upper axle bushings.

Bring it by Steve....we can fix that. :D

Well as attractive as that proposal might be... at about 10 MPG and $2.50+ a gallon I really have to think twice about driving on down, you know? But I may take you up on that if it turns out to be pressed in bushings.

Take a close look at the upper axle bushings.

That is exactly what I am thinking as from prior cursory looks I know there are lots of cracks in the rubber. I need to look closer for shiny metal or metallic dusting/deposits. Maybe I will take some measurements while I am doing the examination :)

Well as attractive as that proposal might be... at about 10 MPG and $2.50+ a gallon I really have to think twice about driving on down, you know? But I may take you up on that if it turns out to be pressed in bushings.
:)
Figure out when and meet me at the shop, I can have them out in about 5 minutes.

Well took a better look... looks like both uppers on the diff have about 1/8" side to side play and like the inner sleeve is seperated from the rubber.

I wonder if it is time to convert to a 3-link yet :)

How is your bolt-on design coming Dennis?

As soon as I get off my lazy ass and weld in the PHB brackets I will set up a BuRP track day to sort it out.

Quit running over the dots in the road.

DO NOT turn left........

Way to bring the tech after resurrecting the dead guys. :sad:

An update...

This weekend I replaced the upper control arm bushings in the rear. The bushings were not too expensive and I had thought they looked ready. I thought I might have found the problem when one of the bushings fell out in my hand without any pressing or pounding. I figure it must not have been seated, although I cannot say that I had noticed.

On the remove/replace process there are a couple of additions to that which has already been written here about using 2" cap, 2" x close nipple, and 1/2" all thread to fashion a puller. I added a 1/2" floor plate to the collection rather than flat metal stock. I also used a 1 1/8" x 1/2" drive socket to pull the rubber out of the shells. No drilling required. And finally with a 12-bolt rear end the driver side is not very accessable. We thought we were going to have to just pound the bushing in. But I figured out that if I cut off one side of the 2" cap it would fit and I could use the puller to press in the bushing. Worked great.

That was the good part, the bad part is that I still have the noise on left hand turns. But with my new found learning and sensitivity to proper bushing fit I have noticed that I have a bushing not seated on the right front lower control arm. So now I guess I get to go rebuild *that* part of the El Camino.

Is it worth considering PU rather than OEM rubber bushings up front?

I suppose I should do ball joints while I am in the neighborhood? Maybe some tall ones :)

Maybe I should just borrow my buddy's welder and tack that bushing in :-/

I hate to resurrect the dead... but what the heck it was my thread after all ;)

I have finally corrected this problem. The culprit: body mount bushings. I think I may have had the original factory bushings from 1968 still in there. They *did* have 'Chevrolet' molded on them! In any case most of the short sides were either gone or close to gone. In particular the left rear was MIA. The frame back there is very flexible and I suspect left turns induce enough twist that I was getting metal on metal. Much quieter backing out across the sidewalk now and no more strange noises around left hand turns.

Really a pretty simple job... once the old junk was out.

I just did the body bushings on my 69. Same thing, had chevrolet on them.

I found the one on the passenger side just behind the door was less than half the thickness it should have been. The rest were all dried and squishy. I have had a big problem in the past, when a certain friend of mine, (about 250 pounds) would get in the car with me, the driveshaft would hit the tunnel. Could never figure it out. Now that the new bushings are in, the problem is cured.

Still haven't had it on the road, middle of winter and all. But excited to see how it handles now.

Jeff