Rear ride height too high

[John S.]

I recently bought a 1969 Corvette Coupe that is very original. One of the few non-orig parts is a 9 leaf rear leaf spring. The car rides 1.5" too high.

8" bolts were used for the spring. I don't want to increase bolt length.

My guess is that the spring is wrong or was poorly constructed and I should order a replacement. Do you have a recommendation of what and where to buy.

[Terry B.]

Re: Rear ride height too high

John,

I did a body off on my '68 a few years ago and have a height issue too. I used an almost new spring that was taken from a '69 car that the owner had replaced for a mono-spring real early in it's life. Some on the TDB said to get the rear wheels off the ground, then loosen the 4 bolts that connect the spring to the differential, put the car back on the ground, then tighten the bolts again. It helped mine some but it is still a little high. 1.5 inches doesn't sound too bad to me but you might try the solution suggested. Good luck!

[Patrick H.]

Re: Rear ride height too high

I recently bought a 1969 Corvette Coupe that is very original. One of the few non-orig parts is a 9 leaf rear leaf spring. The car rides 1.5" too high.

8" bolts were used for the spring. I don't want to increase bolt length.

My guess is that the spring is wrong or was poorly constructed and I should order a replacement. Do you have a recommendation of what and where to buy.

All the replacements are like that. I suspect you will not find one that rides lower.

Any chance the previous owner still has the original? I was lucky enough that this happened and I reinstalled it. If he does not, I'd recommend finding a good used original instead.

[Jeffrey B.]

Re: Rear ride height too high

John,

I belive Patrick is correct when he says all replacements will give you a higher stance in the rear. I replaced the 7 leaf spring on a 69 that I owned for many years and had to use longer bolts to get the correct ride height. I replaced the spring in an attempt to level the cars appearence from the rear, but the spring did not make any difference. The longer bolts allowed the ends of the spring to come down closer to the side walls of the tires but there was clearance. It did look different when viewed from behind. I still have the old spring in my garage, but unfortunately I am in Pennsylvania and you are on the west coast. I have attached a few photos of my car with the longer bolts.

Jeff

[Bill C.]

Re: Rear ride height too high

My car had a slightly different issue, I found once of the springs to be cracked while doing the restoration.

I replaced only the bad spring and used the other originals - the ride height came out nice that way.

So as stated above, finding a used one is the best course.


I would replace the last (lower) one with the same leaf from the newer set. It will give some stiffness back to the original spring set and not make the height turn out badly. This is actually what I did and no regrets .....

[Gary R.]

Re: Rear ride height too high

As stated the aftermarket springs are way off. I have used 7 & 9 leaf steels, most are made in Mexico or Canada but I also used the USA made ones and all are high. The springs are correctly installed and loaded and I had to use the 8" bolts on all of them. The 6.25" stock bolts will have the rear up 2" or so. The spring do not settle as I've read for years. Even so, I still use them over the glass springs which I don't care for.

[Alan S.]

Re: Rear ride height too high

Hi John,
When I put my 71 back together with the original spring I was surprised at the rear ride height being a bit high. I found it took everthing that's supposed to be on the car to get close to the height dimensons given on the 'Trim Heights' sheet of the AIM. The spare tire and FULL tank of gas had more effect than I would have thought... I guess because of their position behind the rear axle's c/l. Driving the car settled the spring a bit too, but remember it wasn't a new spring as Gary describes above..
Regards,
Alan

[John S.]

Re: Rear ride height too high

Thanks for the ideas.

The ride height is too high with the 9 leaf spring. What about removing 1 or 2 of the inner (medium length) springs?

[Terry B.]

Re: Rear ride height too high

John,

I would not take leaves out of the spring nor would I put longer bolts on the ends of the spring. If you have tried the suggestion I made in an earlier post to you, I would live with the 1.5 inches for now. That is not that much to worry with and the car's spring will eventually settle some.

[Gene M.]

Re: Rear ride height too high

John,
I had the same spring issue with a '65 years ago. I took my new correct leaf spring to a local spring shop (Thruway Spring) with the instructions to take out so much to the ride height and balance it from side to side since one was higher than the other.
When done they had my spring disassembled and marked for left and right ends. Since I wanted to repaint it and assemble it myself.
When complete and assembled in the car all was well. Cost was $50 back then. Maybe a bit more cost today.

[John S.]

Re: Rear ride height too high

My car remains too high even after loosening/tightening the mount bolts while the car is weighted. Longer 8" bolts are already installed. If the car had the standard length bolts I'd need some Mickey Thompson L60s to fill the wheel wells.

I bit the bullett and ordered a new 6/3 spring from Eaton Springs. I traded emails and phone calls with Eaton's spring Guru, Mike. Eaton claims that the steel available today is 3/8" thicker than the 1969 steel and Eaton lowers the free arch to achieve stock ride height.

Eaton now ships the springs unpainted. Eaton recommends painting without disassembly and not to paint between the springs. Most of the posts here say to disassemble, paint and reassemble using new liners from Quanta.

Quanta no longer stocks the Ionoklad leaf spring paint. Quanta says they can no longer source the Ionoklad.

So my plan is to clean and paint the assembled spring using Rustoleum Cold Galvanizing Compound. This compound is a bare metal primer and topcoat.

Feedback is welcome regarding spring disassembly or paint choice or anything else I may be screwing up.

The car is shaping up well and entered for NCRS judging on May 22 in San Luis Obispo, CA.

[Steve L.]

Re: Rear ride height too high

I just tested my original leaf springs and a new one from a vendor.
I measued the load on each leaf separately, then added them up for a total spring rate. You can see that the new spring is much stiffer.

This test also showed that my original #2 spring was weak.

Based on this test, I could then mix and match original and new somewhat intelligently in an effort to retain the ride height.

This test is really easy to do. Look at my post a few days earlier.

[John S.]

Re: Rear ride height too high

Thanks for all of the feedback. This forum is v v helpful.

I ended up buying the unpainted Eaton 6/3 leaf spring. I disassembled the spring, painted, reassembled and reinstalled with the standard length bolts. The ride height is good, maybe only 1/2" high. The best advice might be to restore original springs, but if you don't have an existing spring to restore(like my situation) the Eaton is a good choice. Personally I wasn't happy with using longer than stock bolts.

[Gary B.]

How long has the Eaton spring been in?

John,

How many days and miles has the new Eaton spring been in your car? It's possible the 1/2" too high value will diminish a bit with time.

Gary

[Michael F.]

Re: Rear ride height too high

if everyone quit buying from people who produce inferior/inaccurate products the problem would resolve itself, DON'T settle for less than what is right, I won't and don't, close enough is only for horseshoes, I rather have worn out factory than crap from vendors. my 2cents, to each their own.