65 rear spring

[Don H.]

I replaced the rear spring on my '65 about two months ago. It has settled slightly but still sits a little higher than I would like. I am having the alignment checked Wednesday, any suggestions on how to get it a little lower before that? Thanks, Don H.

[Gene M.]

Re: 65 rear spring

Don,
Take it off the car and take it to a good spring shop for re-arching to spec. Agood idea to measure both sides the amount you want the car to drop before you take it off. Mark right and left sides of spring.

[Timothy B.]

Re: 65 rear spring

Don,

Other than installing the original spring or doing what Gene suggests the only solution is to install longer bolts at the ends. These parts may be available in the aftermarket so check from sources like Paragon etc..

[Mike G.]

Re: 65 rear spring

If it's just a little too high, and the old cushions are not split -- reinstall them.

[Duke W.]

Re: 65 rear spring

I replaced the rear spring on my '65 about two months ago. It has settled slightly but still sits a little higher than I would like. I am having the alignment checked Wednesday, any suggestions on how to get it a little lower before that? Thanks, Don H.

Before offering a thoughtful solution, I would need to know answers to the following questions:

1. What spring did you remove? OE? Why did you replace it?

2. What did you replace it with? Type? Mfg? Part number? Tech specs?

3. Did you measure the "D" dimension as outlined in the AIM? Before? With the "new" spring?

I suggest you postpone your alignment job until you get this sorted out.

The viability and quality of responses are in proportion to how much useful information you supply. All we know is that you replaced the spring and you think it sits too high. That's not much to go on.

Duke

[Don H.]

Re: 65 rear spring

I removed the original spring (which had been re-arched) due to major sag. The replacement spring does not have a manufacture name that I could find. It came from one of the large Corvette suppliers and is supposed to be "like original" (9 leaf). If "D" dimension is height, the car does not have correct height tires, they are radials. I did measure at the rear wheel lip before and after. Initially it raised the car 1.5 inches but in almost 4 months it has settled (dropped) 1/8 inch. Thanks, Don H.

[William C.]

Re: 65 rear spring

Well there is some easy to measure guideling information in the AIM, UPC 14, A2 sheet indicates the car should sit level as measured at the bumpers withing 3/16 of an inch front to rear. That takes out any worry about tire sizes and things like that assuming you have the same size tires front and rear, is the reont- rear pumper height from the ground to the top of the bumper within 3/16 front to rear? If so, leave it. If not them only you can decide...

[Ron G.]

Re: 65 rear spring

In a prior post before the factory dropped the body they incorporated weight to the frame to help it settle. They did not actually put weight in the frame but assimulated it to a machine. In those replies I mentioned that my partner in crime, Pualie O. suggested to not fully tighten the 4 bolts under the rear end and the 2 bolts on the end of the rear spring. Then eihter push the car around or possibly drive it back in forth in the driveway until you see it settle. If by some chance you achieve the desired ride height then re-tighten to specs the loose bolts when the vehicle is on the ground. The same principle holds true for the front springs as replacements always make the car sit higher as they are usually taller than the originals.

[Duke W.]

Re: 65 rear spring

If "D" dimension is height, the car does not have correct height tires, they are radials.

The D dimension is independent of tire height and is easy to measure. See your AIM.

I believe that most "spring sag" cases are due to compressed spring link cushions. They can easily loose an inch of ride height. They are a very overlooked component. If the original spring does not have serious corrosion, it is easy to disassemble it, clean it up and paint, then reassemble with new liners. Reinstall it on the car with new link cushions and the ride height and ride will be like new.

Most aftermarket springs don't seem to have the same specs as OE. Too high ride height with repro springs is a common issue.

Duke

[George J.]

Re: 65 rear spring

Duke,
have you seen (or anyone else, for that matter) any NOS seven leaf rear springs for sale?
And Joe, I don't want to hear you chime in that you've got three dozen that aren't for sale.

George

[Gary B.]

Re: 65 rear spring

Duke,
have you seen (or anyone else, for that matter) any NOS seven leaf rear springs for sale?
And Joe, I don't want to hear you chime in that you've got three dozen that aren't for sale.

George

George,

I've looked for NOS rear springs for more than 10 years and I've seen 2 or 3 heavy duty ones come up for auction on e-bay and I think I've seen one 9-leaf. So about one 9-leaf NOS spring per 10 years of looking.

Gary

[George J.]

Re: 65 rear spring

Gary,
that's about what I thought. Thanks.

George

[Gary B.]

Re: 65 rear spring

George,

The last Corvette heavy duty (HD) spring that was sold by GM as a service replacement part was GM #14021604, which was discontinued in Feb of 1991. The HD spring was also used in service to replace the regular, non-HD spring. I don't know when that last non-HD Corvette leaf spring was discontinued as a service replacement part, but it must have preceded the discontinuation of the HD spring, so surely it was a long time ago.

Also, I think the only example I've ever seen of a regular, non-HD, Corvette leaf spring that was on e-bay from a couple of years ago might have been a 10-leaf spring (correct for 75, or 76-77), so not the same as the 9-leaf 64-74 spring. On top of that, based on my somewhat limited inspection of original springs, production regular springs from cars in the early 1970's were not as nicely made (specifically the end cut and taper on the taper rolled ends) as what I've seen on unrestored mid-year cars. So, even if you could find an non-HD NOS spring, it might not be spot on compared to original production springs found of C2s.

The upshot is, I don't think I'll ever find a perfect GM NOS 9-leaf spring for my '66. I opted to restore a good used original GM spring.

Gary

[Timothy B.]

Re: 65 rear spring

Gary,

I have one of those NOS 10 leaf springs I purchased from GM in 1981. I call it NOS but I installed it on my 63 and it sat in the garage until I decided to restore the original nine leaf and install. The 10 leaf spring never saw the road so it's new to me, and I can also report the ride height is exactly the same as my original 63 spring. The spring liners are not plastic and look like aluminum or some sort of metal.

[Gary B.]

Re: 65 rear spring

Gary,

I have one of those NOS 10 leaf springs I purchased from GM in 1981. I call it NOS but I installed it on my 63 and it sat in the garage until I decided to restore the original nine leaf and install. The 10 leaf spring never saw the road so it's new to me, and I can also report the ride height is exactly the same as my original 63 spring. The spring liners are not plastic and look like aluminum or some sort of metal.

Tim,

That's very interesting about the liners. I know for the 1980-1982 HD spring the liners were a zinc-based metal, not graphic-impregnated, polyethylene, but I didn't know that any of the non-HD, regular springs used the metallic liners.

Gary