Leaf Spring Question
Thread Starter
Drifting
Joined: Apr 2001
Posts: 1,401
Likes: 9
From: Holly Springs, Nort Cackalacky / Jupiter, Florida
Leaf Spring Question
Friend of mine has a '64 coupe with a 9 leaf spring. He uses this basically as a daily driver. He does drive it moderately slow and never gets on it. When he had some rear end work done, couple months ago, and the leaf spring was down, he painted each leaf and replaced the rubbers between each, etc....before his mechanic reinstalled.
We were under the car couple weeks ago and noticed that the stack of leafs has twisted quit noticeably. Probably to the order of 1/2"+ from bottom to top of last long leaf. He also has some 'severe' rust/rot on the drivers side trailing arm, to where you can poke a screw driver through material. There is also rust/rot around the frame where that trailing arm hooks up.
I have been trying to emphasize the urgency and safety aspects of these issues, but this mechanic told him "with the kind of diving you do there should be nothing to worry about....." So he is doing nothing about correcting.
I am writing here to find out if I am just being a Mother Hen or if he is headed for some potentially serious trouble and and even more costs down the road. Even if he does drive it like a girl.
(No offense intended to any females here)
RK
We were under the car couple weeks ago and noticed that the stack of leafs has twisted quit noticeably. Probably to the order of 1/2"+ from bottom to top of last long leaf. He also has some 'severe' rust/rot on the drivers side trailing arm, to where you can poke a screw driver through material. There is also rust/rot around the frame where that trailing arm hooks up.
I have been trying to emphasize the urgency and safety aspects of these issues, but this mechanic told him "with the kind of diving you do there should be nothing to worry about....." So he is doing nothing about correcting.
I am writing here to find out if I am just being a Mother Hen or if he is headed for some potentially serious trouble and and even more costs down the road. Even if he does drive it like a girl.
(No offense intended to any females here)
RK
Race Director
Joined: Apr 2005
Posts: 11,265
Likes: 2,131
From: Bowling Green, Kentucky
Headed for trouble. 
Spring twist could be rust/structural issue, or possibly uncured/thick paint used on the springs which is causing some binding/sticking. Hard to tell without seeing......but I would recommend your friend address the rust issues.
Larry
Spring twist could be rust/structural issue, or possibly uncured/thick paint used on the springs which is causing some binding/sticking. Hard to tell without seeing......but I would recommend your friend address the rust issues.
Larry
Drifting
Joined: Dec 2005
Posts: 1,973
Likes: 5
From: Valrico Florida
As you are aware, if the material missing due to rust weren't critical, GM probably wouldn't have installed it. The trailing arm not only maintains alignment, but supports the wheel carrying the weight. The area to which the trailing arm mounts also supports one side of the differential, carries one half of the spring load, supports the body between the body mounts, and is the direct connection to the rear bumper. This is not something to be minimized.
Burning Brakes
Joined: Jan 2005
Posts: 768
Likes: 0
From: Leavenworth Washington
Here's another clue that his mechanic is a wrench short in the tool box: he is twisting the leaf stack and he doesn't get on it hard. There are those who get on it and the leaf stack stays just as it should. Why? If the mechanic is right, that whole deal should be the other way around. Has to be a reason and all you are doing is being a good friend and telling him something just isn't right. Stay with it or the next posting will be the horror story of your bud driving down the road, shelling a trailing arm and twisting the spring/pumpkin right off the car.
Team Owner
Joined: May 2006
Posts: 37,663
Likes: 1,112
From: CA
When the *** of the car hits the ground at..lets say 35 mph...and he is pulled into oncoming traffic...you can then say...See i told you to get it repaired...TAKE his keys from him before he or someone gets hurt...thats what mother hens do..
jack
jack
Le Mans Master
Joined: Feb 2008
Posts: 5,214
Likes: 447
From: NJ Hockey beer league
Poking a hole in a trailing arm is something to take very seriously!! When it fails and the spring bolt pulls through, your friend (or innocent people) could be seriously injured or worse. This car needs to come off the road and get fixed. 
Safety Car
Joined: Nov 2004
Posts: 4,182
Likes: 94
From: going faster miles an hour...with the radio on in browns mills new jersey
The rust issues sound serious and should be addressed.
The spring is more than likely a separate issue. It sounds as though it wasn't torqued properly upon reinstallation.
The spring is more than likely a separate issue. It sounds as though it wasn't torqued properly upon reinstallation.
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Thread Starter
Drifting
Joined: Apr 2001
Posts: 1,401
Likes: 9
From: Holly Springs, Nort Cackalacky / Jupiter, Florida
Great to see y'all are feeling like I do.
I've been telling him, since we've seen the TA's and leaf springs.
So I'll show him your inputs and see if I can at least get him to park the car, if he doesn't want to fix it.
Thanks,
RK
I've been telling him, since we've seen the TA's and leaf springs.
So I'll show him your inputs and see if I can at least get him to park the car, if he doesn't want to fix it.
Thanks,
RK
Melting Slicks
Joined: Oct 2004
Posts: 3,345
Likes: 87
From: Northern MN
St. Jude Donor '13-'14-'15-'16-'17
Just point out to him that if he doesn't either park it now or do something to correct the problem, he may be parking it forever if the darn thing fails while he is driving it. No insurance company in the world would insure him for this type of failure so it would all be out of his pocket to make any repairs.
Team Owner
Joined: Mar 2003
Posts: 26,118
Likes: 1,874
From: Greenville, Indiana
Here's another clue that his mechanic is a wrench short in the tool box: he is twisting the leaf stack and he doesn't get on it hard. There are those who get on it and the leaf stack stays just as it should. Why? If the mechanic is right, that whole deal should be the other way around. Has to be a reason and all you are doing is being a good friend and telling him something just isn't right. Stay with it or the next posting will be the horror story of your bud driving down the road, shelling a trailing arm and twisting the spring/pumpkin right off the car.
I don't think anyone here could give a credible opinion on any rust issues unless you saw the car.
Race Director
Joined: Apr 2005
Posts: 11,265
Likes: 2,131
From: Bowling Green, Kentucky
Another thought on the spring twist:
Currently available spring liners are noticeably thinner than originals. Even later GM NOS are thinner than original.
Two of the four rear spring mounting bolts thread into blind holes in the differential. Using new repro spring liners without shortening the two mounting bolts can (will) result in those two bolts bottoming in the housing and not providing the correct spring clamping force. The other two bolts (of the four mounting bolts) should be tight. This could also cause some problems. Check for this.
I believe that I had to remove 1/8 inch from mine to keep from bottoming out these two bolts....and that was with the relatively thick QUANTA liners. Other available liners are even thinner.
Larry
Currently available spring liners are noticeably thinner than originals. Even later GM NOS are thinner than original.
Two of the four rear spring mounting bolts thread into blind holes in the differential. Using new repro spring liners without shortening the two mounting bolts can (will) result in those two bolts bottoming in the housing and not providing the correct spring clamping force. The other two bolts (of the four mounting bolts) should be tight. This could also cause some problems. Check for this.
I believe that I had to remove 1/8 inch from mine to keep from bottoming out these two bolts....and that was with the relatively thick QUANTA liners. Other available liners are even thinner.
Larry
Thread Starter
Drifting
Joined: Apr 2001
Posts: 1,401
Likes: 9
From: Holly Springs, Nort Cackalacky / Jupiter, Florida
Larry,
That is interesting. I will tell him that, because that could actually be that particular issue regarding the leaf spring twist.
Thanks Much,
RK
That is interesting. I will tell him that, because that could actually be that particular issue regarding the leaf spring twist.
Thanks Much,
RK
Another thought on the spring twist:
Currently available spring liners are noticeably thinner than originals. Even later GM NOS are thinner than original.
Two of the four rear spring mounting bolts thread into blind holes in the differential. Using new repro spring liners without shortening the two mounting bolts can (will) result in those two bolts bottoming in the housing and not providing the correct spring clamping force. The other two bolts (of the four mounting bolts) should be tight. This could also cause some problems. Check for this.
I believe that I had to remove 1/8 inch from mine to keep from bottoming out these two bolts....and that was with the relatively thick QUANTA liners. Other available liners are even thinner.
Larry
Currently available spring liners are noticeably thinner than originals. Even later GM NOS are thinner than original.
Two of the four rear spring mounting bolts thread into blind holes in the differential. Using new repro spring liners without shortening the two mounting bolts can (will) result in those two bolts bottoming in the housing and not providing the correct spring clamping force. The other two bolts (of the four mounting bolts) should be tight. This could also cause some problems. Check for this.
I believe that I had to remove 1/8 inch from mine to keep from bottoming out these two bolts....and that was with the relatively thick QUANTA liners. Other available liners are even thinner.
Larry
Thread Starter
Drifting
Joined: Apr 2001
Posts: 1,401
Likes: 9
From: Holly Springs, Nort Cackalacky / Jupiter, Florida
Ken,
Unfortunately I am out of town at the moment so I have not way to post up some pictures. If issue isn't resolved when I return, I will try to grab a few photos for y'all to see.
Thanks,
RK
Unfortunately I am out of town at the moment so I have not way to post up some pictures. If issue isn't resolved when I return, I will try to grab a few photos for y'all to see.
Thanks,
RK