New Trailing Arm Install
Thread Starter
Instructor
Joined: May 2006
Posts: 223
Likes: 1
From: Kennesaw GA
New Trailing Arm Install
I spent Saturday night (and a good bit of Sunday morning) taking out my old trailing arms, half-shafts, and leaf spring out of the car, and am ready to install the new arms.
I seem to have something different about my car than what most board members have posted, in that my shims for the TA's have solid holes in both ends and there were no cotter pins holding them together.
Now two fat guys rolling around under a Corvette at 4am trying to get both shim packs, the new arm and the bushing spacers in and lined up, may be funny to watch, but don't produce much in the way of a completed project. I'm wondering if I should just slot the existing shims and pound them in after the new arm is installed (as I've heard others doing) Or is there is some trick I'm missing.
Also, are there supposed to be holes in the TA's to run the long cotter pins through to hold the shims in place while loosening the TA pivot bolt?
Thanks in advance!
I seem to have something different about my car than what most board members have posted, in that my shims for the TA's have solid holes in both ends and there were no cotter pins holding them together.
Now two fat guys rolling around under a Corvette at 4am trying to get both shim packs, the new arm and the bushing spacers in and lined up, may be funny to watch, but don't produce much in the way of a completed project. I'm wondering if I should just slot the existing shims and pound them in after the new arm is installed (as I've heard others doing) Or is there is some trick I'm missing.
Also, are there supposed to be holes in the TA's to run the long cotter pins through to hold the shims in place while loosening the TA pivot bolt?
Thanks in advance!
Race Director
Joined: Dec 1999
Posts: 19,610
Likes: 778
From: Forked River NJ
The cotter pin goes through the frame not the trailing arm. This keeps them in place. I have always used the slotted shims and never had to deal the the other type. The trailing arm will actually rest on the cotter pin when it is installed.
Melting Slicks
Joined: Jan 2006
Posts: 3,028
Likes: 2
From: North NJ
My original TA shims did not have "slots" in them either.
Don't remember what the ones I bought from Van Steel look like.
I took pics before i yanked the old ones out so I knew how thick the spacing needed to be on either side so i would just install the new shims to the original specs. I guess you should chose your spacing then line the shims in there then pull the TA bolt thru the holes.
With up-and-down movement of the TA I would hate to see those "slotted" shims slide out.
Which brings me to your next question. A hole that ran thru the shims & TA that held a cotterpin or other instrument that would hold the shims to the TA and prevent them from sliding out would fix the above problem...BUT i have never seen this either. My original shims had only one hole on the bolt end and I did not see a hole in the TA, and I know there is not a hole in my new van steel offset TA's.
Hopefully someone else can chime in and help ya out.
Good luck.
I was up till 3am standing where my engine use to be wirebrushing the frame and cursing at the engine.
Good luck making it thru the day.
Nice 69 car collection you have there.
-B
Don't remember what the ones I bought from Van Steel look like.
I took pics before i yanked the old ones out so I knew how thick the spacing needed to be on either side so i would just install the new shims to the original specs. I guess you should chose your spacing then line the shims in there then pull the TA bolt thru the holes.
With up-and-down movement of the TA I would hate to see those "slotted" shims slide out.
Which brings me to your next question. A hole that ran thru the shims & TA that held a cotterpin or other instrument that would hold the shims to the TA and prevent them from sliding out would fix the above problem...BUT i have never seen this either. My original shims had only one hole on the bolt end and I did not see a hole in the TA, and I know there is not a hole in my new van steel offset TA's.
Hopefully someone else can chime in and help ya out.
Good luck.
I was up till 3am standing where my engine use to be wirebrushing the frame and cursing at the engine.
Good luck making it thru the day.
Nice 69 car collection you have there.
-B
Pro
Joined: Oct 2005
Posts: 505
Likes: 8
From: Houston Tx.
First, the holes for the cotter pins are in the frame, not the T/A's. The cotter pin goes across the T/A opening below the T/A.
Having slots in the shims makes it much easier to install and makes things easier when having a four wheel alignment done. If the shims are slotted, your mechanic can pull them out or put more in as necessary without having to remove the pivot bolt.
One thing I did when replacing my T/A's, was I installed a piece of all-thread where the pivot bolt goes with two nuts on the inside. I then turned the nut to spread the frame opening to allow extra room to insert the T/A and shims. I had to do this because the previous owner did not put enough shims when doing rear end work and crushed the frame inward when he tightened the bolt, so much so the cotter pin in the end of the bolt was about 1/4" away from the castle nut.
Having slots in the shims makes it much easier to install and makes things easier when having a four wheel alignment done. If the shims are slotted, your mechanic can pull them out or put more in as necessary without having to remove the pivot bolt.
One thing I did when replacing my T/A's, was I installed a piece of all-thread where the pivot bolt goes with two nuts on the inside. I then turned the nut to spread the frame opening to allow extra room to insert the T/A and shims. I had to do this because the previous owner did not put enough shims when doing rear end work and crushed the frame inward when he tightened the bolt, so much so the cotter pin in the end of the bolt was about 1/4" away from the castle nut.
Instructor
Joined: Nov 2004
Posts: 162
Likes: 0
Originally Posted by Gordonm
The cotter pin goes through the frame not the trailing arm. This keeps them in place. I have always used the slotted shims and never had to deal the the other type. The trailing arm will actually rest on the cotter pin when it is installed.
The non-slotted, impossible-to-install ones you have are "correct" as far as NCRS goes. I originally had those and exchanged them for the slotted type after I realized that the shop who would do the final alignment wouldn't appreciate them very much. I wasn't using a cotter pin with the non-slotted ones (didn't see a place to put it through, or a reason to use it), but with the slotted ones, the pin went through the frame pocket and shim holes.
Thread Starter
Instructor
Joined: May 2006
Posts: 223
Likes: 1
From: Kennesaw GA
Thanks for the info, I guess I'll order some slotted shims for mine and sell the original shims to a restorer.
There's still so much undercoating on my frame, that I would never have realized that the shims were supposed to be pinned beneath the TA.
Also, am I the only one who finds it a PITA to install the TA bolt with no way to get my fat hands and fingers into the backside of frame? I've done a lot of looking around for tips and tricks, an no one makes a bit deal about how much it sucks to try to get this thing back together... maybe I'm just too sensitive about it. The fishing line idea seems pretty good, but once I found the 'right' sized needlenose pliers, it was a bit easier.
Thanks again.
There's still so much undercoating on my frame, that I would never have realized that the shims were supposed to be pinned beneath the TA.
Also, am I the only one who finds it a PITA to install the TA bolt with no way to get my fat hands and fingers into the backside of frame? I've done a lot of looking around for tips and tricks, an no one makes a bit deal about how much it sucks to try to get this thing back together... maybe I'm just too sensitive about it. The fishing line idea seems pretty good, but once I found the 'right' sized needlenose pliers, it was a bit easier.
Thanks again.
Racer
Joined: Oct 2004
Posts: 379
Likes: 0
From: Thief River Falls Minnesota
No tips for how to put it in with the body on, it's a PITA, maybe you should just do a body-off. 
Seriously though, if you can find someone with smaller hands to do it you'll have much less trouble than with pliers, but if you can't find anyone, pliers are the way to go.
76custompaint
Seriously though, if you can find someone with smaller hands to do it you'll have much less trouble than with pliers, but if you can't find anyone, pliers are the way to go.
76custompaint
Account disabled by user request 5 Jan 09
Joined: Jan 2005
Posts: 261
Likes: 1
1968 and early 1969 did not have the cotter pin ...
(the pictured shims are correct if that's what came off your car)
If you have an assembly manual, go to UPC4, B3 and you'll see the cotter pin was added sometime in November 1968 (my book is hard to read the exact date).
You don't have holes drilled in the frame, so you can't use a cotter pin. You'll need to reinsert the shims in exactly the same order as you took them off, and it can be a bear of a job ... but it's very doable.
I have a November 1968 dated coupe, and did them myself. Nimble fingers help ... (:-). Also, after you're done, you'll probably need a professional alignment anyhow, and a good Corvette shop can usually do that.
I've heard that some early cars have used the slotted shims and drilled their own frame hole.I've not seen one, so I don't know what, if any, problems to watch for. Whatever works for you .....
Good luck ....
(the pictured shims are correct if that's what came off your car)
If you have an assembly manual, go to UPC4, B3 and you'll see the cotter pin was added sometime in November 1968 (my book is hard to read the exact date).
You don't have holes drilled in the frame, so you can't use a cotter pin. You'll need to reinsert the shims in exactly the same order as you took them off, and it can be a bear of a job ... but it's very doable.
I have a November 1968 dated coupe, and did them myself. Nimble fingers help ... (:-). Also, after you're done, you'll probably need a professional alignment anyhow, and a good Corvette shop can usually do that.
I've heard that some early cars have used the slotted shims and drilled their own frame hole.I've not seen one, so I don't know what, if any, problems to watch for. Whatever works for you .....
Good luck ....
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Melting Slicks
Joined: Apr 2004
Posts: 2,008
Likes: 38
From: Space Coast Gator Territory
Originally Posted by 76vette1
First, the holes for the cotter pins are in the frame, not the T/A's. The cotter pin goes across the T/A opening below the T/A.
One thing I did when replacing my T/A's, was I installed a piece of all-thread where the pivot bolt goes with two nuts on the inside. I then turned the nut to spread the frame opening to allow extra room to insert the T/A and shims. I had to do this because the previous owner did not put enough shims when doing rear end work and crushed the frame inward when he tightened the bolt, so much so the cotter pin in the end of the bolt was about 1/4" away from the castle nut.
One thing I did when replacing my T/A's, was I installed a piece of all-thread where the pivot bolt goes with two nuts on the inside. I then turned the nut to spread the frame opening to allow extra room to insert the T/A and shims. I had to do this because the previous owner did not put enough shims when doing rear end work and crushed the frame inward when he tightened the bolt, so much so the cotter pin in the end of the bolt was about 1/4" away from the castle nut.
The cotter pin hole is located just below the double steel on the outside of the TA pocket. If you don't have them, they can be made with a 12 inch drill extension on a hand drill. Yes, I had to do this on my 69 frame and with a small file was able to make a perfect fit.
Pro
Joined: Oct 2005
Posts: 505
Likes: 8
From: Houston Tx.
Originally Posted by GruntyPants
Also, am I the only one who finds it a PITA to install the TA bolt with no way to get my fat hands and fingers into the backside of frame?
Race Director
Joined: Apr 1999
Posts: 10,866
Likes: 717
From: Beverly Hills/Pine Ridge Florida
68-69, up to mid 70 used the 2 holer shims. After that, they changed to the slotted shims.
The slotted shims require a hole in the frame and a large, about 8 inch, cotter pin.
The 2 hole shims were used from early 63 to early 70. Chuck
The slotted shims require a hole in the frame and a large, about 8 inch, cotter pin.
The 2 hole shims were used from early 63 to early 70. Chuck
Thread Starter
Instructor
Joined: May 2006
Posts: 223
Likes: 1
From: Kennesaw GA
Thanks for the info guys... I've got a pile of the slotted shims being donated from a couple of sources so I should be good to go.
FrankVincent - Thanks for the PM.
I'm hoping to have this thing move under its own power this weekend, first time in 21 years!
FrankVincent - Thanks for the PM.
I'm hoping to have this thing move under its own power this weekend, first time in 21 years!
Le Mans Master
Joined: Oct 2004
Posts: 5,269
Likes: 54
From: Orlando Florida
St. Jude Donor '05
Originally Posted by GruntyPants
Also, am I the only one who finds it a PITA to install the TA bolt with no way to get my fat hands and fingers into the backside of frame? I've done a lot of looking around for tips and tricks, an no one makes a bit deal about how much it sucks to try to get this thing back together... maybe I'm just too sensitive about it. The fishing line idea seems pretty good, but once I found the 'right' sized needlenose pliers, it was a bit easier.
Thanks again.
I used super glue and glued the bolts to the needlenose pliers... it worked great
