Rear Suspension Questions
Thread Starter
Always Shiftin'
Joined: Jun 2000
Posts: 4,028
Likes: 939
From: Central Florida
2025 C7 of the Year Finalist - Modified
2024 C7 of the Year Finalist - Modified
2023 C7 of the Year Finalist - Unmodified
2019 C5 of Year Finalist (stock)
Rear Suspension Questions
I have always noticed that my Corvette ('72 LS5) rides low in the rear. If I hit a medium dip in the road my exhausts (pipes just below rear diff.) bottom out (it probably doesn't help that my fat azz is in there!! :eek: ). So today I decided to lift it up and look around to see what all I need to do back there.
Before lifting the car, I looked underneath and noticed that the leaf spring (HD 7 leaf) is sitting perfectly flat. No arch at all. Is this normal??
Right now I have it up in the air with the rear spare carrier out of the way. Other than dirty, everything looks OK. The bushings aren't too bad. Nothing looks bent. Other than some minor surface rust/scale, the trailing arms look OK. I just figured that I would post this message and see if anyones has recommendations for what I should check while under there.
My primary concern is the leaf spring. Any help would be appreciated!! :cheers:
[Modified by QikStik, 2:30 PM 3/10/2002]
Before lifting the car, I looked underneath and noticed that the leaf spring (HD 7 leaf) is sitting perfectly flat. No arch at all. Is this normal??
Right now I have it up in the air with the rear spare carrier out of the way. Other than dirty, everything looks OK. The bushings aren't too bad. Nothing looks bent. Other than some minor surface rust/scale, the trailing arms look OK. I just figured that I would post this message and see if anyones has recommendations for what I should check while under there.
My primary concern is the leaf spring. Any help would be appreciated!! :cheers:
[Modified by QikStik, 2:30 PM 3/10/2002]
Le Mans Master
Joined: Feb 2000
Posts: 7,032
Likes: 2
From: Newburgh NY
Re: Rear Suspension Questions (QikStik)
On mine the rear spring had a hefty arch in it when I installed it but I believe the earlier ones were flat or near flat when installed. Might have lost it's bounce though.
One option is to pick up a longer bolt set to raise the back a little. The other would be to replace it.
One option is to pick up a longer bolt set to raise the back a little. The other would be to replace it.
Pro
Joined: Jul 2000
Posts: 654
Likes: 0
From: Now Frozen in Michigan
Re: Rear Suspension Questions (QikStik)
Qik-
It's not a good thing to be bottoming-out all the time. I believe the spring should retain some of its arc under static load. After all, it's the arc that buys some spring travel. I think new springs are very inexpensive and easy to install. And as posted above extended mt bolts will buy you some time, but coupled with a new spring will improve ride/handling! From what I've seen, most rear springs (steel) last about 10 yrs under normal use and then signs of fatigue start to show. I'm looking into glass springs for my repl. I can't wait to compare the ride/handling difference! Good Luck -Rod :chevy
It's not a good thing to be bottoming-out all the time. I believe the spring should retain some of its arc under static load. After all, it's the arc that buys some spring travel. I think new springs are very inexpensive and easy to install. And as posted above extended mt bolts will buy you some time, but coupled with a new spring will improve ride/handling! From what I've seen, most rear springs (steel) last about 10 yrs under normal use and then signs of fatigue start to show. I'm looking into glass springs for my repl. I can't wait to compare the ride/handling difference! Good Luck -Rod :chevy
Drifting
Joined: Oct 2000
Posts: 1,825
Likes: 56
From: Shawano WI
Re: Rear Suspension Questions (QikStik)
FE-7 springs have very little arch to them compared to a standard 9 leaf spring. An easy check is to look at the half shafts when the car is on the ground. you want them to be as level as possible. If they are angle up towards the tire then the spring is sagging.
Drifting
Joined: Sep 1999
Posts: 1,908
Likes: 0
From: Manassas, VA, USA
Re: Rear Suspension Questions (ROD NOCK)
Qik-
I believe the spring should retain some of its arc under static load. After all, it's the arc that buys some spring travel. ... I'm looking into glass springs for my repl. I can't wait to compare the ride/handling difference!
I believe the spring should retain some of its arc under static load. After all, it's the arc that buys some spring travel. ... I'm looking into glass springs for my repl. I can't wait to compare the ride/handling difference!
As to bushings, just looking okay doesn't tell you much. Get yourself a prybar and pry on the suspension parts and see how much play there is in the bushings. It's kind of a feel thing (don't get macho under there and break anything prying), but they should not have much play.
Melting Slicks
Joined: Aug 2000
Posts: 2,310
Likes: 1
Re: Rear Suspension Questions (Pete79L82)
An easy check is to look at the half shafts when the car is on the ground. you want them to be as level as possible. If they are angle up towards the tire then the spring is sagging.
Hmmm... I don't think I've heard that before. Thanks for that tip Pete.
QikStik, FWIW, I noticed my 9 leaf spring was flat when I purchased my car. I replaced it with a 7 leaf and was disappointed when I saw that one was flat too. Hopefully, as others have said, that's the way the 7 leaf is supposed to be. Anyway, I did notice improvement in the ride, but with the minimal clearance (4" maybe at the exhaust under the diff) these cars have, it's easy to bottem them out. I'm not recommending it (because some say there are safety risks in rear end collisions), but I picked up about 1" to 2" in clearance when I removed my spare tire & tub. That's a lot of lost weight back there. As others have said, you might want to start with longer end bolts (or adjust the existing bolts if they're long enough) to add some clearance.
Good Luck.
Hmmm... I don't think I've heard that before. Thanks for that tip Pete.
QikStik, FWIW, I noticed my 9 leaf spring was flat when I purchased my car. I replaced it with a 7 leaf and was disappointed when I saw that one was flat too. Hopefully, as others have said, that's the way the 7 leaf is supposed to be. Anyway, I did notice improvement in the ride, but with the minimal clearance (4" maybe at the exhaust under the diff) these cars have, it's easy to bottem them out. I'm not recommending it (because some say there are safety risks in rear end collisions), but I picked up about 1" to 2" in clearance when I removed my spare tire & tub. That's a lot of lost weight back there. As others have said, you might want to start with longer end bolts (or adjust the existing bolts if they're long enough) to add some clearance.
Good Luck.
Thread Starter
Always Shiftin'
Joined: Jun 2000
Posts: 4,028
Likes: 939
From: Central Florida
2025 C7 of the Year Finalist - Modified
2024 C7 of the Year Finalist - Modified
2023 C7 of the Year Finalist - Unmodified
2019 C5 of Year Finalist (stock)
Re: Rear Suspension Questions (jerryp58)
Great information! Thanks!! I think I've just about decided to replace the spring and do a minor rear suspension overhaul. Can't afford the trailing arms right now.
Thanks again everyone!!! :cheers:
Mark
Thanks again everyone!!! :cheers:
Mark
Melting Slicks
Joined: Mar 1999
Posts: 2,845
Likes: 2
From: Apex NC
Re: Rear Suspension Questions (QikStik)
Mark, before you dive in and replace the spring, check a few things. First off, check the frame height measurements as specified in the AIM to see if the height is OK to start with. Others mentioned using longer spring bolts, but that'll move you in the opposite direction. Shorter bolts would be needed to adjust the ride height to be higher than it is now. Also, do the bushings on the spring bolts look OK? These can compress and cause the rear to sag slightly.
Shannon
Shannon
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Thread Starter
Always Shiftin'
Joined: Jun 2000
Posts: 4,028
Likes: 939
From: Central Florida
2025 C7 of the Year Finalist - Modified
2024 C7 of the Year Finalist - Modified
2023 C7 of the Year Finalist - Unmodified
2019 C5 of Year Finalist (stock)
Re: Rear Suspension Questions (sb69coupe)
The spring bolt bushings do need to be replaced. A real good friend of mine is a mechanic. He is coming over tomorrow to look at it. He had a '71 LT1 a few years ago that was doing the same thing as mine. So I hope he will be able to help.
I will also check the ride height as you suggested! Thanks!!!
Mark
I will also check the ride height as you suggested! Thanks!!!
Mark
Race Director
Joined: Nov 2000
Posts: 11,872
Likes: 12
From: Waterloo ontario Canada
Re: Rear Suspension Questions (QikStik)
sb69coupe has got it right. If you want more ground clearance you want shorter bolts not longer. If you are hitting the exhaust pipe shortening the bolts will buy you some extra clearance. My fairly new 7 leaf is also flat and I would prefer a slight arch. To me a flat spring has lost it's bounce.
Le Mans Master
Joined: Oct 2001
Posts: 5,943
Likes: 3
From: Wildwood IL
Re: Rear Suspension Questions (norvalwilhelm)
Replacing the old compressed spring bushings with either poly or rubber will also lift that sagging rear. If only that would work on women!! :jester :jester
Melting Slicks
Joined: Aug 2001
Posts: 2,043
Likes: 1
From: Elkhorn WI
Re: Rear Suspension Questions (Silvr77)
Replacing the old compressed spring bushings with either poly or rubber will also lift that sagging rear. If only that would work on women!!
Race Director
Joined: Dec 1999
Posts: 11,096
Likes: 990
From: Sierra Foothills CA
Re: Rear Suspension Questions (Silvr77)
Replacing the old compressed spring bushings with either poly or rubber will also lift that sagging rear. If only that would work on women!! :jester :jester
Thread Starter
Always Shiftin'
Joined: Jun 2000
Posts: 4,028
Likes: 939
From: Central Florida
2025 C7 of the Year Finalist - Modified
2024 C7 of the Year Finalist - Modified
2023 C7 of the Year Finalist - Unmodified
2019 C5 of Year Finalist (stock)
Re: Rear Suspension Questions (Les)
I posted this same topic on the "Factory Correct Resto" forum. I also got some good feedback over there! I realized after one of the responses that I had made a Major Mistake. Here is my last response over there:
OK, I'm allowed this one mistake, right? :crazy:
Mark
OK....I'll admit it......I'm a dumbazz!!! And thanks Chuck for helping me realize it!!
Facts:
1) The only '72 model that had the HD F41 suspension was the ZR-1 option. (per NCRS Judging Manual)
2) All other '72 models (including LS5 optioned) had the std 9 leaf spring.
3) Just got back from counting the leafs in my spring, and guess what....9 leafs!!
I had assumed since I had a big block car that the suspension was heavy duty! Well, we know what happens when we Azz/U/Me!!
Now...since I have a Standard 9 Leaf Spring, and the spring is flat (no arch at all), is it safe to believe that I need a new spring???
Chuck: Thanks for helping me see the light AND the extra two leafs!!
Mark
Facts:
1) The only '72 model that had the HD F41 suspension was the ZR-1 option. (per NCRS Judging Manual)
2) All other '72 models (including LS5 optioned) had the std 9 leaf spring.
3) Just got back from counting the leafs in my spring, and guess what....9 leafs!!
I had assumed since I had a big block car that the suspension was heavy duty! Well, we know what happens when we Azz/U/Me!!
Now...since I have a Standard 9 Leaf Spring, and the spring is flat (no arch at all), is it safe to believe that I need a new spring???
Chuck: Thanks for helping me see the light AND the extra two leafs!!
Mark
Mark
