C3 rear spring confusion

[tom444634]

Weather finally getting warmer here so I decided to start the tear down of my rear suspension for a much needed overhaul. My rear spring has 9 leafs but they are all arched and there was a spacer between each spring. I thought there were two straight ones, leafs 8 and 9, and no spacer between 6 and 7.

This came off of a fairly original 71 LS5 and judging by the amount of rust and grime, I don't know if this spring was ever off of the car. Past two owners confirmed that it wasn't and that takes it back to 1978. Don't know what happened before then......

Photo is with the spacers removed.

Ideas anyone?

Tom

[Joe L.]

Re: C3 rear spring confusion

Tom-----

I don't think that any spring of this configuration was ever originally used on a C3 Corvette. I wouldn't rule out the possibility that a "substitute" spring might have been used during a shortage and other-sourced springs used. I really, really doubt, though. GM had 2 sources for these springs as it was.

The interesting thing about this spring is that it has the "upturned" leaf ends. Original springs used this configuration. However, from what I can see of the leaf ends in your photo, it does not appear to be the configuration the original exhibited. Rather, the configuration is much more similar to the reproduction springs sold be Eaton Detroit Spring which have come on the market in the last 10 years, or so. I didn't realize that there were any out there like this before that.

[tom444634]

Re: C3 rear spring confusion

Thanks Joe. I always seem to get the odd ball things! This spring has definitly been on the car for a long time. Interesting thing is that the "up turns" you mention are wider on some leafs then on the others. Don't know if that means anything....

I have more pics if anyone is interested.

For what it is worth, the front springs are 3931826 code HV. This is a non-AC car built 9/70.

[Gary B.]

Looks like a 75-77 10-leaf spring.

Tom,

Unless I'm mis-counting leaves in your photo, what you have there is a 10-leaf spring. Ten leaf, one-stage springs were used in 1975 (GM # 346906) and in 1976-1977 (GM # 362153), at which point my reseach data ends. These 10-leaf springs did indeed come with 9 liners, or 1 between each and every leaf.

Gary

[Joe L.]

Re: Looks like a 75-77 10-leaf spring.

Gary-----

Yes, I forgot about those. Also, I believe those springs became later GM SERVICE replacement springs for earlier models.

[Dennis C.]

Tom, You have an incredibly high membership #... *NM*

[tom444634]

Re: Looks like a 75-77 10-leaf spring.

Gary,

Thanks for the input. I suppose the spring got changed somewhere in the late 70's. Do you have any recommendations as to where I could get a correct spring for the car?

Tom

[tom444634]

Re: Tom, You have an incredibly high membership #.

Yeah, how about that! I mis-typed when I was setting up my account and didn't catch it until it was too late. Thought it was kind of unique though....

[Rob M.]

Re: Looks like a 75-77 10-leaf spring.

Tom,

I think the best source for a reproduction spring for your car will be from:

Eaton Detroit Spring
1555 Michigan, Detroit, MI 48216
phone 1-313-963-3839 fax 1-313-963-7047

http://www.eatonsprings.com

Good luck,
Rob

[Philip C.]

Re:high membership #AN NCRS ANOMALY.. *NM*