Ride Height

[Bill M.]

I bought a 66 convertible a couple of years ago the rear was sagging so i figured that the spring was shot. I just replaced the spring with a standard spring and the ride height remained the same. i have 25" from floor to rear bonding line. My other mid years are 26". My spring bolts are 6 3/4 " . I cannot see any thing out of the ordinary. The doors and convertible top deck open and close fine. Any ideas?

Thanks
Bill

[Donald T.]

Re: Ride Height

Bill,

Did you also replace the spring cushions?

[Bill M.]

Re: Ride Height

Don

Yes i also replaced the bushings in the struts.

Bill

[Stephen L.]

Re: Ride Height

Smaller diameter tires?????

[Bill M.]

Re: Ride Height

No stock size

[Terry M.]

Re: Ride Height

No stock size

What about the other midyears? Do they have original spring(s), cushions in good condition, and stock size tires?

[Bill M.]

Re: Ride Height

Terry

Yes the 67 spring replaced 5 years ago bought from L I corvettes the 65 came with all new. The 66 sits as though there is an 800 pound gorilla sitting on the rear deck

[Duke W.]

Re: Ride Height

The most common source of rear sag is compressed spring link bushings. In most cases, installing a new set, which is cheap and easy, will restore normal ride height and dramatically reduce ride harshness.

OE springs are usually okay to use as long as they have not lost significant material due to corrosion, but the spring should be removed and disassembled for a thorough inspection.

Most available replacement springs, even those that are advertised as "original" DO NOT meet OE specs for either rate or ride height, and for this reason alone, one should not replace the OE spring unless a detailed inspection shows signficant loss of material due to corrosion that renders it unserviceable.

The "ride height measurement" you took are not really valid. You should check the ride height using the method/specs in the CSM and AIM.

Duke

[Bill M.]

Re: Ride Height

Duke

I never thought about just the bushings being bad. I have my 67 spring i will see what the AIM says and if it looks positive i will swap out springs. The 66 bushings were compressed to the size of washers.

[Duke W.]

Re: Ride Height

The spring link cushions are overlooked by most owners even though they are inexpensive and easy to change. Based on your report of their compressed state at least an inch of ride height has been lost, which is very noticeable when looking at the car.

A few years ago I helped a neighbor install new spring link cushions on his '77. Not only did they restore OE ride height, but the reduction in ride harshness was absolutely dramatic - almost unbelieveable!

So I now know why Chevrolet engineers specified those thick, soft cushions on the rear spring link, but they don't last 40 years. They should be inspected regularly and if hardened/compressed they should be replaced. This could be in as little as five years, even if the car has accumulated few miles.

The fact that they are under constant compression load is what kills them, so it's a time, not mileage issue.

Duke

[Bill M.]

Re: Ride Height

Having changed the bushings and the spring and remaining at the same height i must have something else wrong.

[Duke W.]

Re: Ride Height

...or maybe the replacement spring doesn't meet OE specs for rate and/or ride height, which is typical.

I suggest you disassemble, inspect, clean, paint as desired, and reinstall the OE spring with the new cushions.

You listed the length of the spring link bolts, but I don't know if they are correct, so you should verify with known original bolts for your year and options.

Duke

[Bill M.]

Re: Ride Height

Duke

I will do so. the bolts are the same length as the other 2 sets. I wonder if the springs in the frount were wrong could they cause the rear to squat?

Bill

[Bill M.]

Re: Ride Height

I wonder if the springs in the frount were wrong could they cause the rear to squat?

Bill

No. RF-LR and LF-RR can affect each other, but not both front to both rear.

[Bill M.]

Re: Ride Height

bill

Thanks i noticed last night that i left some type of metal strap wrappped around each side of spring i removed them but did not have time to lower car off lift. I am going to do that and hope for best