Trailing arm shims?
Thread Starter
Instructor
Joined: Dec 2007
Posts: 245
Likes: 2
From: Jersey shore NJ
Trailing arm shims?
I've read a bunch of posts that say to put the shims back into the trailing arm equal on both sides. I'm getting ready to pull mine off to put new bushings in them and they have 3 shims one the inside and 1 shim on the outside. should I just put them back that way? I will be taking it for a alignment later.
Racer
Joined: Jul 2007
Posts: 397
Likes: 0
From: Warren IL
I think what they meant was right inside should be the same as the left inside and the right outside should be the same as the right outside. I am sure if I am wrong that someone with correct me on this one.
Safety Car
Joined: Nov 2004
Posts: 4,359
Likes: 57
From: Mundelein Illinois
If you know the T/A's are original from factory, I would set it up the same way. When I pulled my shims out I labeled the OEM shims drivers outside & driver inside and did the same for passangers side. My arms where set up pretty much in the center of the frame. I'm no expert. but I would think you want the T/A pretty much in the center.
Take your extra shims when you go for an alignment and tell them if the rear is off here are shims to make it right. As long as it's a quality shop they will set the rear accuratley. Some other shops may tell you it's fine and set the front alignmnet to the rear as is.
Take your extra shims when you go for an alignment and tell them if the rear is off here are shims to make it right. As long as it's a quality shop they will set the rear accuratley. Some other shops may tell you it's fine and set the front alignmnet to the rear as is.
Melting Slicks
Joined: Dec 2000
Posts: 3,364
Likes: 303
From: Lansdale 19446 PA
2024 C3 of the Year Finalist- Unmodified
St. Jude Donor '10-'11, '15, '19
I was told if I put the same unmolested trailing arms in - say I just painted them, put the shims back in the exact locations. If the arms were rebuilt, changed or the bushings were changed, reinstall with an equal amount of shims on each trailing arm.
The trailing arm pocket hole was suppose to be a specific width allowing for an equal amount of shims on each side of the trailing arm. But - bubba would get in there and over torque the bolt collapsing the pocket. You may have to force some shims (prefer stainless) in one side but they should be tight. Once I figure out how many I need on each side, if necessary, I will install the thinner ones first then force a larger one in last.
The trailing arm pocket hole was suppose to be a specific width allowing for an equal amount of shims on each side of the trailing arm. But - bubba would get in there and over torque the bolt collapsing the pocket. You may have to force some shims (prefer stainless) in one side but they should be tight. Once I figure out how many I need on each side, if necessary, I will install the thinner ones first then force a larger one in last.
Advanced
Joined: Oct 2004
Posts: 65
Likes: 0
From: Long Valley NJ
I just finished replaceing my trailing arms and placed equal spacing on each side. The shims that were in there were rusted so badly that I could not detirmine how many I had in each side. I plan on taking the car to have it aligned as soon as it is on the road.
Team Owner
Joined: Oct 2004
Posts: 23,831
Likes: 10
From: Springfield MO
St. Jude Donor '07
I've read a bunch of posts that say to put the shims back into the trailing arm equal on both sides. I'm getting ready to pull mine off to put new bushings in them and they have 3 shims one the inside and 1 shim on the outside. should I just put them back that way? I will be taking it for a alignment later.
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Race Director
Joined: Apr 2003
Posts: 19,344
Likes: 654
From: Tampa, Florida
Be sure to us slotted shims versus shims with a hole. If you install shims with a hole the alignment shop will have to remove the bolt to do a shim change. Do you think they'll actualy do that?
Drifting
Joined: May 2006
Posts: 1,425
Likes: 0
From: Seattle Wash.
My '68 came with holes in the shims, no slots. The stainless ones I ordered have a slot and a hole. What is the best way to install the new shims? Push the slotted end up to the T/A bolt and slide the cotter pin through the hole at the bottom of the T/A pocket, or should I slide the bolt through the hole end of the shim and leave slotted end pointing down to the T/A pocket? For installation purposes, it would seem easier to have the slotted end on the T/A bolt, but relying on a long cotter pin as the only way of securing or keeping the shims in place is worriesome. Any help is much appreciated.
Thanks.
Thanks.
Safety Car
Joined: Oct 2006
Posts: 3,930
Likes: 15
From: Calgary Alberta
My '68 came with holes in the shims, no slots. The stainless ones I ordered have a slot and a hole. What is the best way to install the new shims? Push the slotted end up to the T/A bolt and slide the cotter pin through the hole at the bottom of the T/A pocket, or should I slide the bolt through the hole end of the shim and leave slotted end pointing down to the T/A pocket? For installation purposes, it would seem easier to have the slotted end on the T/A bolt, but relying on a long cotter pin as the only way of securing or keeping the shims in place is worriesome. Any help is much appreciated.
Thanks.
Thanks.
Drifting
Joined: May 2006
Posts: 1,425
Likes: 0
From: Seattle Wash.
Are you sure? The cotter pin that came with my shims is easlily 4 - 5" long and did not come packaged with the T/A bolts, which did have a new castle nuts and cotter pins. The AIM for my car shows the shims as having holes on both ends with no forks or slots and having a bolt go through the hole.
Pro
Joined: Jul 2005
Posts: 592
Likes: 0
From: ElP TX
Are you sure? The cotter pin that came with my shims is easlily 4 - 5" long and did not come packaged with the T/A bolts, which did have a new castle nuts and cotter pins. The AIM for my car shows the shims as having holes on both ends with no forks or slots and having a bolt go through the hole.
on the shop owners face when I showed him the new shiny shims with SLOTS instead of the old HOLES ONLY. They did an excellent job.
Safety Car
Joined: Oct 2006
Posts: 3,930
Likes: 15
From: Calgary Alberta
Are you sure? The cotter pin that came with my shims is easlily 4 - 5" long and did not come packaged with the T/A bolts, which did have a new castle nuts and cotter pins. The AIM for my car shows the shims as having holes on both ends with no forks or slots and having a bolt go through the hole.
Safety Car
Joined: Oct 2006
Posts: 3,930
Likes: 15
From: Calgary Alberta
Drifting
Joined: May 2006
Posts: 1,425
Likes: 0
From: Seattle Wash.
I'm positive. The older corvettes had holes on both ends. to get the car aligned or to change the shim stack, you had to remove the bolt and alter the shim size, then reinstall the bolt through the shim's holes. GM got smart and switched to a fork design instead. Now, all you had to do was loosen the trailing arm bolt, insert or alter the new shims, then retighten the bolt. The fork allows you to slip it over the trailing arm bolt as opposed to having to pull the bolt out of the pocket entirely. This is a much better design, and once the 4'' cotter pin is installed, those shims will never come out.
Drifting
Joined: May 2006
Posts: 1,425
Likes: 0
From: Seattle Wash.
Race Director
Joined: Nov 1999
Posts: 10,643
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From: Foxfield CO 1970 Convertible
No matter what you do, when you remove the TAs, you'll need a new alignment after you put them back in. You can add shims back where they were to make it closer to correct - that way the trip to the alignment shop won't be as scary. If you don't do the alignment, tire wear will be excessive and handling may be impaired.