My wandering 74 Eldorado!

[danjarrett1]

Season’s Greetings to all my fellow Caddy affectionados!!  My beautiful 1974 Caddy Eldorado convertible is a dream to own and drive! However, she seems to wander about the road some. I’ve always know that big GM cars from the 60’s and 70’s have never enjoyed tight steering like new cars but this is a bit excessive. Has good shocks, new tires, tie rod ends and ball joints are tight but has play in the steering wheel. When driving down a straight stretch of road, I can move the wheel left or right three to fours inches and nothing much happens, feel like I’m chasing it a bit down the road, always playing catch up. I know my stabilizer link bushings are bad, I have the parts to replace, but I can’t imagine it causing that much play. Any ideas on tightening things up or are they all that way???

[bcroe]

The rag joint connecting the bottom of the steering column to
the steering box may have a mushed out rubber disc.  You can
see this by watching it while rocking the column back and forth. 

Here is mine.  A simple repair is a problem. 

Your ball joints could be fine, esp with lower mileage.  In that
situation I just replace the rubber bushings. 
Bruce Roe

[danjarrett1]

Could be the problem Bruce! Is that rubber bushing fairly easy to find (OPI and th like?) I presume it does not require removing the steering column inside the car but rather the joint can be separated and the rubber bushing replaced?

[danjarrett1]

Would the part needed  be referred to as the steering coupler assembly?

[Dave Shepherd]

Yes, some parts books list as such.  After you replace this, then check for excess play in the steering box, another common issue.

[bcroe]

In 76 book the Eldo is more complex with a U joint from the steering
column, then the shaft assembly (including the rag joint) down to the
steering box.  Other cars combine all this into one assembly.  My
experience is the rag joint is the problem, but only the entire
assembly was sold.  The rag joint is riveted together. 

There are some rubber/fiber disc rebuild kits made, but I did not find
any to fit this application for all my cars of the era.  I note the limo
had a double disc, apparently to avoid the problem.  There is a steel
U joint available, which fits but transmits a lot of road vibration.  I
tried one, but it got loose too. 

I asked a steering place to rebuild it, they could not. 

Eventually in desperation I gathered a bunch of kits, noting some were
a lot thicker and robust but not for GM.  I did manage to adapt one
of these with mods to make it all fit.  Took a lot of fitting, stepped
bolts, locking nuts, etc. 

Putting the entire shaft assembly back in the car has its own problem,
any distortion makes this extremely difficult. 
good luck, Bruce Roe

[Mike Josephic CLC #3877]

I'll interject another possibility since I have a
1973 Eldorado (since new).

These cars are VERY sensitive to the type of
tires you put on them due to the front wheel
drive design.  I've had tires on mine that caused
the car to "wander" at certain speeds (called "radial
walk").  Some brands do this, some not.

Since you mentioned that you did install new
tires -- did your car have this problem prior
to that with the OLD tires?

Mike

[danjarrett1]

Mike, yes...same problem with old tires. I installed a brand new set of Coker white walls, appropriate size and load for the car. I maintain that the tire looks skinny to me but they are the factory recommended size. Not much variance allowed on tire size given the style of the rim and the minimal clearance between the rear wheel fender skirts and the tires. I did find a replacement steering coupler rag joint, dorman makes them, and Larsen does as well. Rubber and steel flex joint with splined center, bolts into place. It is on order now, less that $40

[bcroe]

I did find a replacement steering coupler rag joint, dorman makes them, and Larsen does as well. Rubber and steel flex joint with splined center, bolts into place. It is on order now, less that $40 

Given how may of these are in the field, the proper replacement is
badly needed.  Please let us see what parts worked for you.  Bruce Roe

[danjarrett1]

Will do

["Cadillac Kid" Greg Surfas 15364]

Dan,
I might suggest you find the exact cause of the play before you start changing parts. Play can be anywhere in the steering from the previously discussed "rag joint" to the steering box to the pitman arm/drag link to the inner tye rods.
I would suggest you get the car in a position where you can observe the action of the steering linkage and have someone move the steering wheel back and forth.  By starting at the input side of the steering coupler and working downward you can see which parts move in relationship to each other. There are a lot of components subject to wear and damage.
Greg Surfas

[danjarrett1]

Greg.....agreed! That is my intention. There is an initial universal joint extending from the firewall, then the rag joint, then into the steering box. On first glance, they appear to be ok but I do intent to put the car on a lift and check out those components and the ones you mentioned. I do have a good relationship with local tire dealer and he will hoist the car and allow me to inspect. When I first bought the car about 16 months or so ago, the only real complaint I had was obvious deterioration of the stabilizer bar control links, everything else appeared to be in fairly good shape given its age, no obvious excessive wear at least. I really don’t know how to “test” the condition of the steering box, how would I test for excessive play? What are the allowable play specs? Once hoisted, checking the control arms, pitman, idler arm, tie rods ends and more are pretty straight forward I expect. I’ll get the car in this week and report my findings

[bcroe]

I am thinking, the slack may show up better with the wheels planted
on the ground.  Bruce Roe

[Glen]

I agree with Bruce, the wheels need to be on the ground.  Have your helper move the steering wheel as much as s/he can without moving the wheels on the ground.  Any movement would then be slack. 

[danjarrett1]

That’s true! With a load on the car the steering problem would manifest, anxious to see conditions of tie tod ends, drag link and more. I can do that easily enough in my garage with the Car on ramps

[TJ Hopland]

Yep ramps would be a good way.   Without the help of power steering most assistants won't be able to put enough pressure on the wheel to make them turn and cause a danger of falling off the ramps. 

I would have them rock the wheel back and fourth and start looking at the wheels.  Just start at the tie rod end and follow the path all the way to the steering wheel shaft.  You may find something like the idler arm that is causing most of the movement.   THings like tie rods have to be pretty bad to really cause problems but the further from the wheels you get the more things get amplified.   

[danjarrett1]

Some of you wanted me to supply information about the replacement rag joint when I located one.see attached photo’s. Haven’t installed yet, piece looks well built, robust!

[bcroe]

Thanks, perhaps you could tell us the thickness of the fiber section,
which might be thicker and more robust than original.  If it fits right,
I will be buying half a bucket full of those for my cars.  Bruce Roe

[danjarrett1]

Appears to be about 12mm in thickness

[bcroe]

Thank you for that research.  I see that my 79 up couplings have
only about 0.36 inch thick rubber disc, about 2/3 of yours.  AND
I see one like yours is in my collection.  This like many others will
not fit my 79, but it might fit your 74.  The 3.5 inch dia and larger
bolt spacing will not work for me.  BUT I also found LARES CORP
has a 205 model that looks like a good 79 fit.  I will need to try
it out, lots easier than home brew.  Bruce Roe