Toms cutlass

Over time, the rear coil springs tend to weaken and the correct OE stance of the car begins to sag in the rear. I replaced front and rear coil springs close to 30 years ago (at most 5K miles over those years). Anyone have experience with rear air shocks in the "A" body? Recommendations? Issues? Should I just replace the springs - again?

quaddriver

monroes, 20psi min. had a set im my 72 and my 74 until I rolled my own suspension on the 74 and went 'au natural'....

BUT

GM prefers to not have live loads on the shock mounts. yes, I know G66 has been around for many decades, but it was an assistance to PROPER springs, not a replacement or augmentation of weak springs. it would be best to add in a set of cargo coils first or find springs with the proper rate. The A bodies can consume springs that physically fit from many makes within GM and many models and many decades.

Toms cutlass

Thanks, that's what I recall. I'll go with new springs. There's a spring shop close by that originally made these springs for me, so they could make whatever spring spec I want. I'd like to get just a little more strength. I already have the rubber spring mounts on the axle which adds an inch or so to the overall spring height/length.

MDchanic

A new set of CargoCoils will run you about $100 and make you happy.

As Quad noted, there are many other options as well.

Air shocks have potential failure points of their own, and aren't that great as shock absorbers.

- Eric

edit: crossed posts with you.

oldcutlass

Springs is the best way to go, you'll hate the air shocks.

Toms cutlass

Thank you all.

Any suggestions on spring type / specs? I like the "ride" with the current OE springs, Monroe shocks and rear sway bar, but the tired sag look just isn't becoming of a matador red Cutlass Supreme convertible with Super Stock II wheels.

oldcutlass

Post a side view of your car.

Toms cutlass

Here you go ... 5 year-old pics ... nothing more current.

oldcutlass

The second pic really is deceiving but by the first pic it sits nicely.

76olds

I had monroe air shocks in my 76 for several years before puttung in some vista cruiser wagon coils.
They were ok but only lasted a few summers. I agree with others coils are the way to go. The pic you posted looks ok IMO.

Eric

quaddriver

I dunno if Joe has the spring info specs for your car - tyou can ask...he seems to have everything. If you have the original info you can get the spring rate, free height and installed height made for you.

how it works: the spring has a height when it is just sitting there, measure that, then once it is installed it has an installed height which is generally on those car an inch plus, less. that difference times the spring rate is the preload. then you lower the car to the gound and the spring compresses more, the curb height times the spring rate plus the preload is how much the spring is carrying to get to where you sit. if the rear is down by 2 inches for example, then you need to take the known load you are carrying, then subtract the desired curb height from the installed height and work the equation backwards to get the desired spring rate.

it may well be that the rate they made for you was correct, but tempering was faulty or corrosion changed the metallurgy and it is not working out. check out rock auto - they list a crap load of springs for the car, and I like to get ones with the larger diameter wire....they have constant rate and variable rate and price+ shipping will be $75 or less

Toms cutlass

Thanks again for your helpful replies and re-schooling me on coil springs. If Joe P. checks in with coil spring rates, I'll be set either to have them made, or get a set from Rock Auto. I just saw a thread where he may have an air bag kit installed inside the coil spring.

Toms cutlass

No rear springs listed at Rock Auto for a convertible. I'll have to check with Joe for the spring rate and get them made to order.

76olds

I'm sure someone here with a convertible will chime in and give you some advice on the coils. If not try and post in the suspension/handling section being specific with your question.

Eric

quaddriver

1967-1972 GM A body: all interchange. Moog CC-501. And these are variable rate so I'd personally pick em

Toms cutlass

All the same spring regardless of ragtop, coupe or 4-door? Thanks for your reply.

quaddriver

yessir, only the 442 w car has a different spring (that you dont have to use) with a slightly lower installed height and a slightly higher rate - but that is that same for the GTO, SS and GSX of the same years

Toms cutlass

Moog CC-501 it is. Thanks again.