VCCA Home Forums TECHNICAL - 1945 AND NEWER 1958-1960 Air-Ride Suspension on '58 Full Size

As I was crawling around under the Bel Air a couple of weeks ago, I got a closer look at something that was brought to my attention by a body shop guy. Inside the center of the rear coil springs are a pair of heavy rubber cylindrical air tubes with tire-like valve stems at the bottom. I know that Chevy introduced the air suspension at around this time, but I understood it to be an option that was an alternative to standard shock absorbers. My car has standard shocks as well. Is this something other than the Air-Ride option?

Hi pkennedy58BelAir,

Sounds like someone has installed modern air bags to your suspension.

Thanks for your response Ray. I appreciate you taking the time.

I don't really think they're an aftermarket item. I inherited the car and Grandma wasn't much into customizing her ride. They're also cylindrical and fit vertically inside the coils of the spring. The only modern bags I've seen are the round pillow-type. Maybe the pillows are used with a leafspring suspension. I'm no expert - barely a novice, actually.

I'll check the assembly manual to see if they're pictured, and if they resemble the Air Ride option of the day. Maybe I can find some GM markings if I do a little cleaning on them.

The air suspension that Chevrolet introduced in 1958 was more professional that air bags with a stem below.

Recently I had a 1957 Cad in the shop with the air suspension. It was so complicated that Cadillac had ran double lines to each of the 4 corners. One line provided the pressure, the other line was routed back to the engine compartment and to an exhaust valve and silencer. Cad didn't want the owner hearing the escaping air noise when the system called for lowering the rear end. The SSSSssssss noise would have the owner running to the dealer to fix a LEAK.

Chevrolets system was not near that complicated, however it was not so primitive that a valve stem protruded through the bottom of the springs.

You have Air-Lift air bags in your rear coil springs...These were available as helper springs beginning back in the early '50's...The "NASCAR" stock car racers used them..Were a commonly found helper spring, especailly on a car with coils in the rear in those days.Also could be used on leaf spring cars.They are still made today.The 1958 cars with "Level Air" had air bags not coil springs, front or rear...but they did have a shock absorber on each corner.
The 1958 Level Air cars had a lot of problems and Chevrolet paid to change them over to conventional coil springs.They removed the engine mounted compressor and lines and other necessary plumbing.The Level Air cars had the front shocks external mounted as the shock normally went in the center of the coil spring.If it originally was a Level Air car the front upper shock brackets will still be sticking out of the frame .Also it would have had the Level Air name plate below the deck lid (or holes for it).
The Level Air system had a leveling valve (2 front and 1 rear if I remember correctly) and the car remained at the same riding heigth when loaded.
The leveling valves were one problem, they would function incorrectly and one end of the car would sit real high or low.Or an air bag would leak and the car would settle to the ground.All the 1958 GM cars had a version of air suspension and only Chevrolet used its simple version.Was available on just the rear on Frod products..Chevrolet advertised it for 1959 but I have never seen a 1959 with it.The dealer knew better than to order a car with it after mid 1958.

The Lincoln Town Car uses a version of it, and has for the last 15 years or so.They have it in the rear only.The older Continentals had it on all four corners and was built into the struts.Not unusual to see them driving around with the bottom dragging on the pavement.

I remember when I was an apprentice at NCR some of the apprentices from Delco Products joked about going into business. They were going to by 2 X 4 lumber and cut them into 4" pieces and put them inpackages of four. They would sell them to people with air ride. When the air bag gave out the owner could jack the car up and insert the block to hold the car at a normal level.

When the 1957 Cadillac was placed on the show room floor it was blocked up at all 4 corners with blocks and a system that held air for 24-48 hours was considered satisfactory. A warning light was placed on the dash and it was unsafe to operate the car until the red light went out.

I/ve seen those inflatable bags years ago in Australia on Chevs that pulled caravans

This car came equipped from the factory with the 348 w/4BBL and power nothing ("Armstrong" Power Steering, as I like to call it). I know I don't have a compressor under the hood or anything else, including plumbing or name plates, associated with the Level Air system and these don't appear to have been used much in recent years. There's some pressure in them holding their shape but they yield to a poke from a finger so they're not providing any significant support to the suspension.

So it sounds like these inflatable spring lining bags are an aftermarket ride enhancing something or other, maybe something Grandma's second husband had put in to make him feel like he was in a Caddy. They're not original, and we don't use this car to pull a trailer, so off they come! Maybe I'll clean them up and let the kids kick them around the yard or use them for flotation in the pool this summer. Thanks to all of you for your input, this was a helpful discussion.

The air bags were not "ride enhancing" -probably made the ride more firm.Their function was to keep the rear end from sinking when a load was carried.The amount of "lift" was controlled by the air pressure in them.

We're jumping back and forth between two strings now Gene, so I'll copy this over from the '61-'64 string and carry it on here where it's more applicable to the year.

"The 1958 348 (heavy) and Power Glide(heavy) often settled down in the front and it was necessary to replace the coil springs.
In general 1958's had many problems and I would have never believed there would be any aroung 48 years later.Still one of the best looking cars Chevrolet produced.

Would not be too difficult to add Power Steering - or to make steering easier install a 1959-64 non -PS steering gear.It had a lower ratio (more turns) but made parking more effortless.If your were ever to install radial tires it would be a must."

Phew! We're coming around full circle. I didn't take a close look at the suspension up front yet, but I'm wondering if these coil spring air bags might be of more actual use up there where all that weight is? Would a set of Chevy Truck coil springs offer better support up front?

Or maybe there's already another set of air bags up there if they put them in all the way around. Like I said, there's no trailer hitch, so it doesn't make too much sense that the air bags would only be in the back, unless Grandma needed to keep the springs tight in the corners while she was outrunnin' the revenuers with a trunkload of 'shine.

Interesting you should mention power steering at the same time I was mentioning it on the other string as well. PS and PB are desired upgrades for coming years. (A/C would be nice, but it doesn't look too practical as it dominates about 30 pages in the assembly manual.) I'd like to have it all done by the 50th anniversary if it's not a budget-buster.

The wide whites I have on it are radials, which give it more control on the highway but, you're right about this, it steers on the surface streets like a battleship without the tight turning radius. Not too much trouble for big burly me, but when the boss drives it she struggles with it a bit.

As for it being one of the best looking, you'll get no argument here. I read a great article in Collectible Automobile magazine that talked about how the GM design boys did a panic end run around Harley Earl to re-style the '59's while he was in Europe, thus making the '58 all-new body style a one-year only transition.

Thanks again Gene. There's that other six quadrillion words. I'd be interested to know more about the other problems you mention that are inherent with the '58's as well. I need to know what to look out for and head off any problems before they cost me more than I can afford.

There was no panic run to change the 58 design, but rather the entire GM line was going to have a platform change in 59. You will recall that the 58 Chevy/Pontiac roof line was used in 57 by Buick Olds and Caddy. They just wanted to have all lines change at once. I agree that it is a surprise that any 58's around considering that they really did not have much of a resale when they hit lots as used cars in the early to mid 60's. And when they were only 10 years old they really looked out of place. I never was a fan of the 58 style,(front) but then again what would I know I always loved the 59 and 60 and those are real love or hate designs.
Enjoy
John
PS all Level-air 58's had a script on the passenger side of the dash about 5 inches long

This article in the current Collectible Automobile magazine referred to the re-design of the '59's being in response to one of the GM designers driving past a Chrysler facility in '57, looking through the fence as he drove past and seeing their new models (300's?) for '58 or '59. He brought another senior designer over during their lunch hour to look at them (the article names the designers), noting that they were lower and sleeker than what they had cooking at GM.

Harley Earl was said to be directing more of the same for the new GM's, big and heavy with "100 pounds of chrome". The article has many photos of the full-size clay models comparing what they were working on to what they ended up with. The re-design was sudden (panic may be an exaggeration) and when Mr. Earl returned, he was surprised at the departure from the original plan, to say the least. (Not that I would ever say the least!)

That story has been in at least 20 magazine articles in the last 15 years.One publication/author copies the other, and so it goes.
There is no doubt that the GM designs were going in the wrong direction starting with the 1957-58 Olds, Buick and Cadillac. (1958 Chev and Pontiac shared no body parts with those cars - just the over weight fat design).It would have been more logical for Chev and Pont to have adopted the 1958 body in 1957 and ran it for two years as it was well accepted, at leat compared to the 57-58 Olds and buick.
The designs need to be looked at as to how they were recieved by the public when the cars were new.Actually the 1958 Chevrolet was well accepted and was one of the only cars to increas sales over 1957 (Rambler the other).The 1959 was my favorite next to the '58....Back then the buyers objected more to the increased size of the 1958 ,still larger in 1959, than to the looks of the cars.

Is your '58 gold or coral - its difficult to determine on the picture.Either color will be difficult to match as the metallic colors fade over time.Don't depend on ordering paint and haveing it blend in.I have spent more money on trying to have the original paint on my '50 duplicated with very poor results - and it a simple light gray non-metalic color.
A book that you may find informative and intresting is "Impala & SS" Muscle Portfolio by Brooklands books (United Kingdom)...It has many road tests of 1958-72 Fiull sized chevrolets. including several on 1958 348.It only about $20 and sold thru the larger book vendors.

If the story is run so often and so widely then I'm not surprised it had a familiar ring to it. I'm pretty sure I read a less detailed version in a book or magazine somewhere along the line. The clay models depicted are quite a study though. They were definitely going for something different, but from the looks of the models I'm not too sure what that was. One had regular single headlights on the fenders and a vertical pair of high beams in the center of the grille that just looked strange.

Still, if you look at the models in sequence from Tri-5's through early '60's, there's really a distinct change at the '59 that's almost like an anomaly. The '58 looks like it belongs in between there, it's an advancement of the '57 body style, but then you get this low, flat '59 that looks like it's wearing a cape and flying low to the ground. Good looking car, and far nicer than the mid-60's models would later be, but not at all inspired by the previous generations from the looks of them.

My '58 is anniversary gold over honey beige. I have a neighbor three houses down who owns a restored '58 Biscayne that's repainted to a very close approximation of Cay Coral over white. I have a few pictures of the two sitting side by side in the street that I'll have to post some time.

I'm not counting too much on a perfect color match, but most of the spots I have to cover are really small, and more in the beige areas than in the gold top. Hopefully those will be more forgiving, but better than bare metal as long as I keep it smooth. The gold is sprayed over the beige, so that will require some skilled blending and rubbing down.

In any case, I'll look at samples sprayed on a non-porous sheet first, and maybe cut my teeth painting my fender skirts or two-tone on my lawnmower before I bite the bullet and go crazy on the actual car.

http://clubs.hemmings.com/clubsites/chevytalk/index1.html has two links to the history of the '58 and '59 cars if anyone is interested. I just thank goodness though that Earl's proposed '59 Models did not go through as they were so awful.

I have just seen on ChevyTalk a photo of the LevelAir badging on a '59 Chevy. I have never seen one before, but it's like the '59 FI cars..they were reputedly available but has anyone ever seen one? I suppose add in there 348-engined Sedan Deliveries! However a few genuine FI '59s have turned up over the years.