Got my 57 Cadillac running and driving like a top. This is not my first big custom but this thing floats back and forth on its 100% stock suspension like its a boat stuck in 1 foot seas. It also follows the road like crazy and with the light power steering its very easy to over-correct. I have gotten the car up on the lift and all the rubber in is good shape, shocks are not leaking.. Nothing is moving around with the pry bar as well. Its definitely left to right and not back to front. I have Bias Bly 15' champions on car right now at 36 psi, I image they are the squishiest link in the car. Car follows the road like crazy as well but that is the tires and the light steering I think. . What is the consensus here. Add a monster of a aftermaket sway bar. Stiffer front shock's. Is there any way to remove a bit of the power assist to help keep the car a little bit more controllable. I am a 28 roaster sort of guy but with a bad back this is getting me out of the garage a bit more so I would like to fix it if possible.
First lower the tire pressure to around 30#. You need wide tires with a tread pattern that won't follow lines in the road.
Yes, you need shock absorbers that work, on all corners. That should be a cheap and easy start. No suggestions re. steering, but I know what you mean. Too much air in the tires?
Try new shocks. The stock ones pooh out after 20000 - 25000 miles even if they are not leaking or rusty. You might get a front end alignment, it is probably off. And let the tires down to 32 PSI. The steering on them was touchy and floaty at the best of times. HD shocks may help. I just thought, does it have tubular shocks? If it has the old lever action they may need to be filled with oil. Jack oil works. I know they still had lever shocks in 55 and possibly 56.
put some radials on it. my old 62 Caddy would just glide on down the road like I was on a cloud, straight down the freeway. 95,000 miles and nothing new or rebuilt. it needed an alignment as well because in the few years I had it the front tires wore funny.
^^^^ What he said. ^^^^ My '49 Studebaker Champion sedan was the same way until I put radials on it. Then it was sweet as could be to drive.
Radials and better shocks for sure. If the toe is out, the car will grab the lines in the road. Get that checked.
Do the shocks pass the bounce test? That's the litmus for shocks. Springs get squishy and saggy too after 60 years. However new springs will most likely raise the ride height. A powersteering pressure regulator will solve some of the light steering but it has some compromises. A good alignment is the perfect place to start, if it's still lacking after that maybe adding some more caster will help.
Side to Side =Sway bars front and rear, Some ride owners who had there sway bars removed because they had radical adjustable suspensions ,realized the importance of why the factory started adding sway bars,keep in mind the weight of the car determines how big of a sway bar you need
If tires are right,if shocks are right and all sub gromits are right an set,swaybars right,and it still feels funny to you,add some extra caster[+2* over stock set]
I'd start by lowering your tire pressure. 36 PSI sound like way too much for bias plies. The factory specs that I could find list 24 PSI front and rear (from a 1956 Shop Manual). I usually run my bias plies around 26-28 PSI, but trouble shoot to find that perfect level for your car. When these cars were designed, the squishy bias-ply tires were a part of the suspension equasion. Lower pressures enlarge your contact patch, remove stiffness from the tread (which causes tramlining), and in effect makes the tire a shock-absorber.
Exactly my thoughts. My Falcon also had 24 psi all around for recommended pressure. 36 psi is not a bias ply pressure. You are taking away the tire's ability to absorb squirm with pressure that high. Cosmo
I had 13" bias ply tires on my Dart when I got it..followed all the lines in the road and it was pretty un-nerving. I put radials on it and a sway bar on the front and what a difference...course good shocks help too.
are you saying that the car "wanders" or are you just overcorrecting? If wandering, and other things are correct try adding more toe in, caster may also help. How does it do when braking? does it wander more? if so that would be a sign of more toe in needed.
Just because suspension components look okay doesn't mean they are. I have built and restored Hundreds of 50"s era cars over my career and those parts get hard , they can seize up on pivot points and mounting bolts, taking much of the proper suspension action out of the car. And it seems the bigger the car the more it seems to magnify the problems. Just so we don't start throwing good money after bad. Put the car up on a set of heavy duty jack stands. Mount them under the front A arms and the rear axle tubes that way the weight of car loads the suspension as if it where sitting on the ground. Get on a creeper and while you are under the car [ be careful] have a friend [ preferably in access of 200lbs ] push up and down on the bumpers first the front then the rear. check for any binding or clunking sounds. Check the actions of the shocks if they look old or they are the old oil filled ones, put them on your list for replacement parts but get the gas filled ones! And I don't want to hear one word from anyone about them not being traditional !! One at a time see if you can loosen up the various bushing bolts and rotate the bolts in the bushings , If you cannot then add to the list. If you can rotate them, it would still be good idea to back them out and apply some grease or better yet anti sieze , [ just be prepared if your like my friend Gary to come out looking like the Tin man from Oz!! lol] . Check ball joint movement, tie rod, drag link, pitman arm and any other steering linkage or pivot points. Check steering box play, there is a adjustment bolt usually on top, loosen the lock nut and adjust the lash which would be the amount of movement between the turn of the steering wheel and the response of the pitman arm, and reset the lock nut. Just don't tighten it up to much ,there needs to be a certain amount of free play. Test driving between those adjustments will help find the happy medium. After you have decided that all these parts are in either good working order or have replaced then , have it totally aligned. Not just the toe and go, have castor , chamber and the toe set to spec,s. Now find a friend with either a early 70,s to mid 80,s chevy 1/2 ton or someone with another Caddy, Buick ,Olds or Pontiac with 15" 5on 5 bolt pattern wheels and a good set of radial tires close to the height of your bias plys , bribe them with several refreshing beverages and put their tires on your car and test drive. You can Buy Gangster whites radials when you know it works. With that said I would add front and rear sway bars if possible on a car this size just on principle! and 32psi all 4 corners ! There hwy tires not wrinkle wall slicks! I am 60 years old and have been at this along time!! Larry
Use at a minimum Monroe Sensa-trac for shocks. Do the sway bars. Research a real old time alinement man.
I would still start with shocks and alignment, if everything else checks out good. They are the easiest and cheapest to do. They may solve the problem, if they don't you can look at other mods or new tires.
Turns out is like 90% the tires. Sway bar had some adjustment which made things a bit better. Shocks and springs were fine. Put the tires at the correct PSI and made a very tiny bit of difference. Friend lent me a set of wheels and radial tires car drives like a completely different animal. No tracking, no sway and the thing will actually turn, less road noise as well. So looks like I need to find a set, car would look wrong with a set of blackwall tires but they are 50% the cost. Might just drive on what I have for a few months until I can find a set of radials whitewalls on sale.
Check with Diamondback on the tires...they have the best whitewall radials in the business...balance correctly, whitest whites around and stay white...and they do give a HAMB discount but you have to ask for it...get on their mailing list as they do run "sales and specials". I just bought two for $189 each. I run 215-75R15's on my '55 (avatar) with 38 #'s of air in the tire and have absolutely no problems (Diamondback recommends that pressure) and I put thousands of highway miles on my car... Your Caddy would look strange with blackwalls...good luck... R-
I had a 60 Chevy with the coils cut short. Used wagon coils all around. then put all urethane bushings everywhere. Heavy sway bars front and rear. Ran low profile 16 inch 50 series in front and 40 in the rear (don't judge, it was in the early 90's) The car sat super low and road like it was on rails. No sway at all. Loved it.
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