Trailing arm shims
Thread Starter
Drifting
Joined: Nov 2016
Posts: 1,960
Likes: 579
From: Pittsburgh PA
Trailing arm shims
Anyone installed slotted shims and NOT put the cotter pin in?
I decided to use the later slotted shims on my 68(originally no slots) so I would need to drill holes for the pin.
Just curious if anyone chanced not installing the pins?
I decided to use the later slotted shims on my 68(originally no slots) so I would need to drill holes for the pin.
Just curious if anyone chanced not installing the pins?
Melting Slicks
Joined: May 2012
Posts: 2,192
Likes: 343
From: Allenton Wisconsin
My early 6t8 had the holes in for a cotter pin even though there was no pin. As blue427 mentioned I didn't have the cotter pins in and went for a test, with in 10 miles they were gone. T
Is my vette stock?? HAHA
Joined: Oct 2015
Posts: 20,209
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From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
2020 Corvette of the Year Finalist (performance mods)
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Bubba used the 69 and later slotted shims on my 68 and didn't use the cotter pin,, luckily I noticed before they fell completely out, it was a close call. I bought the correct 68 but after getting the shimming right with the 69 slots I didn't want to pull them apart and put in the correct ones so I drilled and wired the 69 slotted ones in. No problems all summer, 3000 miles later. Need to sell the 68s and the extra factory 69s i have
Le Mans Master
Joined: Nov 2003
Posts: 5,772
Likes: 694
From: Maryland
St. Jude Donor '05, '09, '15
I've used the slotted shims in my 65 for 10 years and never lost one. If you are not aware midyears do not have the cotter pin hole in the frame. The shim pack should be tight enough the last shim has to be driven in. Then push the pack down into the trailing arm pocket and tighten the nut/bolt. Done. If you still have concerns one of the tricks some midyear guys do is use one double hole shim in each pack. That way one shim is secured through the bolt. Then use slotted shims to set the toe. Use safety wire or a wire tie to secure the whole shim pack together. Shims cannot fall out because of the one on the bolt.
Tom
Tom
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Drifting
Joined: Mar 2009
Posts: 1,461
Likes: 361
From: Monson MA
I just completed this task. Early 68 (Oct. 67 )
no holes for TA shims. I used the shims with slots and just drilled the holes to except the cotter pins to keep the shims in place. Moving on to other task to perform.
no holes for TA shims. I used the shims with slots and just drilled the holes to except the cotter pins to keep the shims in place. Moving on to other task to perform.
Former Vendor
Joined: Aug 2006
Posts: 76,656
Likes: 1,852
From: Jeffersonville Indiana 812-288-7103
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
We just did this to the very non original 68 in our shop. Drilled the holes and installed the cotter pins. Why? Because it makes the rear wheel alignment way easier and less expensive on the customer.
Imho,
Willcox
Racer
Joined: Nov 2010
Posts: 310
Likes: 25
From: Brisbane Australia
When I got my 68 it just had slotted shims that were taped together and just tucked down into the gap in the frame. Lasted 10k miles till I rebuilt the trailing arms. Put new ones back in after but didn't tape them and popped one out on my first test drive.
Pro
Joined: Feb 2014
Posts: 607
Likes: 122
The High Priced, Highly Recommended Alignment shop I was refered to by a tire shop did not put the cotter pin my alignment shims for my trailing arms. They fell out after three hundred miles. I took the car back and the first words out of his mouth were "It wasn't my fault, if you pay me again, I will do the job over". I can highly reccomend a shop to never take your car to. Let me know.
Drifting
Joined: Jul 2015
Posts: 1,765
Likes: 254
From: Catlett VA
If you invest in a 90 degree attachment for your drill it makes drilling the holes a little easier since you can get the drill inside the fender well. Plus- get the hardest, best quality drill bit you can find. The steel in the frame is almost as hard as the cheap drill bits and will wear them dull in no time.
Racer
Joined: Aug 2013
Posts: 264
Likes: 58
From: Virginia
I replaced my trailing arms on my '70 a couple years ago.
Whoever worked on that car before me, used slotted shims and no cotter pins, they were taped and pushed down like 'azza2u' and Sky65 mentioned above.
They had been in there a long time. Rusted up, super tight.
I replaced with stainless steel slotted shims and pins.
Whoever worked on that car before me, used slotted shims and no cotter pins, they were taped and pushed down like 'azza2u' and Sky65 mentioned above.
They had been in there a long time. Rusted up, super tight.
I replaced with stainless steel slotted shims and pins.
Is my vette stock?? HAHA
Joined: Oct 2015
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From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
2016 C3 of Year Finalist
Cobalt steel drill bits are great on hardened steel. I used them when I gunsmithed