Rear Leaf Spring Help
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Pro
Joined: Mar 2009
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Rear Leaf Spring Help
I have a few questions I could use some help with.
1. Are the leaf springs in a 78-82 wider than the 68-77 and are the 4 spring mounting bolts designed to sandwich the leaf spring for added support? I just replaced the 3.08 in my 68 with a 4.11 that came out of a newer model and the spring mounting bolts are 7/16 and not 1/2 like the original. The original, with the 1/2" bolts, were snug against my leaf on both sides (sandwiched the leaf) but now with the smaller 7/16 bolts, there is a nice gap between the bolts and the spring, does this gap matter? Below is a picture and the bolts have not been tightened yet..
2. Also, my new leaf spring bushing kit only has one bushing cup, which side the does the cup go, the bottom of the leaf spring or in the trailing arm pocket? My original had cups on both ends..
3. When installing my new trailing arms, should I lubricate the pivot bolts to help reduce issues when it comes to removing them again in the future?
1. Are the leaf springs in a 78-82 wider than the 68-77 and are the 4 spring mounting bolts designed to sandwich the leaf spring for added support? I just replaced the 3.08 in my 68 with a 4.11 that came out of a newer model and the spring mounting bolts are 7/16 and not 1/2 like the original. The original, with the 1/2" bolts, were snug against my leaf on both sides (sandwiched the leaf) but now with the smaller 7/16 bolts, there is a nice gap between the bolts and the spring, does this gap matter? Below is a picture and the bolts have not been tightened yet..
2. Also, my new leaf spring bushing kit only has one bushing cup, which side the does the cup go, the bottom of the leaf spring or in the trailing arm pocket? My original had cups on both ends..
3. When installing my new trailing arms, should I lubricate the pivot bolts to help reduce issues when it comes to removing them again in the future?
Racer
Joined: Jan 2008
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Yes there is a difference. I believe the earlier models had a 2 1/4 inch wide spring and the later model had a 2 1/2 inch wide spring. I just ordered a rear spring for my 1977 and I had to go out and measure which width the spring was. So I guess that was the transition year.
Burning Brakes
Joined: May 2008
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From: Stratford Ontario
It looks to me You have the opposite of what I ran into.Your rear cover is probably for a 2 1/2 inch leaf and Your leaf is only 2 1/4 inch wide. I bought a 73 vert that the cover was broke so when I replaced it I bought a hd cover. It only fit 2 1/4 inch leaf, I realized this after I had installed it. So I had to get a 2 1/4 wide spring to fit.My spring also uses one two piece cup if that helps? I can't see yours to see what you mean by one cup.Good luck and it looks nice and clean under there.
Timsride
Timsride
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From: Graceland in a Not Correctly Restored Stingray
Yep, early C3's had larger spring to diff cover bolts, which means there's also a 1/4" inch difference between early C3 and later C3 spring widths. You can get a pair of spring spacers for a '78-'79 w/FE7 to take up the difference, so no need to change spring or cover to solve this.
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It looks to me You have the opposite of what I ran into.Your rear cover is probably for a 2 1/2 inch leaf and Your leaf is only 2 1/4 inch wide. I bought a 73 vert that the cover was broke so when I replaced it I bought a hd cover. It only fit 2 1/4 inch leaf, I realized this after I had installed it. So I had to get a 2 1/4 wide spring to fit.My spring also uses one two piece cup if that helps? I can't see yours to see what you mean by one cup.Good luck and it looks nice and clean under there. Timsride
TimsrideHere's a picture of the bushing cup I'm referring too. The kit only comes with one bushing cup
Thread Starter
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Yep, early C3's had larger spring to diff cover bolts, which means there's also a 1/4" inch difference between early C3 and later C3 spring widths. You can get a pair of spring spacers for a '78-'79 w/FE7 to take up the difference, so no need to change spring or cover to solve this.
Since I'm running a single mono leaf, I assume I will have to cut the height on the spacers? I guess that's still alot better than having to buy a new spring.
Team Owner
Joined: Mar 2002
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Here's a picture of the bushing cup I'm referring too. The kit only comes with one bushing cup
1 steel bushing cup
2 rubber bushing dome pointed down
3 washer
4 nut
5 cotter pin
Le Mans Master
Joined: Apr 2007
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From: Graceland in a Not Correctly Restored Stingray
Sorry, didn't account for this being a 'glass spring (haven't had my coffee yet). The one's I suggested might work fine with it, but if not seems logical there ought to be a set available for your particular combination. I'd check with where you got the spring.
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Thread Starter
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I just found some other spacers that are "tubes" that slide over the bolts. Those would be alot easier to cut down if I cant find the correct height spacers due to the shorter height of the mono leaf.. Heck, I could probably just make my own..
Thank you, that's the info I needed.. Glad I ask because I was going to mount the cup in the trailing arm pocket
I believe that goes into the spring (from below). The inner lip should be a sloppy fit with the hole in the end of the spring. So looking from the bottom of the spring, the installation order would be
1 steel bushing cup
2 rubber bushing dome pointed down
3 washer
4 nut
5 cotter pin
1 steel bushing cup
2 rubber bushing dome pointed down
3 washer
4 nut
5 cotter pin
Advanced
Joined: Apr 2006
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From: Gold Coast
I had a chat with VBandP about spring widths a few months ago. Appparently all their springs are all the same width (2 1/4 inch). There are no twisting loads on the mount so the spacers aren't required and it should be fine with the gap. That was direct from their tech guy.
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Le Mans Master
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From: Graceland in a Not Correctly Restored Stingray
