biuliano

I have a 1967 corvette and am trying to install new trailing arms. I was forced to burn off the strut rods on both ends. I ordered new strut rods and cam bolts to replace what was there. Here's the thing, the cam bolts are 1/2 inch bolts and the strut rod holes that the cam bolts fit thru are 5/8. I called the people who sold me the product and spoke with there tech support guys. They measured an existing corvette and confirmed that the bolt was 1/2 and the strut bolt hole was 5/8. Now, I don't claim to be a rocket scientist but this just doesn't make any sense to me. Can anyone tell me what I'm missing?

Donny Brass

Do you have the metal bushings ??

Pilot Dan

You are not missing a thing, the strut rods (at least originals) should have a 1/2" hole. I just measured again some NOS GM bushings I have here to confirm what I though and they are 1/2 inch. Don't know where you got these parts from, but I would return them and try one of the other vendors. I bought a repro set a while back from Willcox and they fit perfect with the old hardware. Pilot Dan

Chuck Gongloff

You're not missing anything.

You're a victim of a running change.

Original midyears had the correct diameter rubber bushing and corresponding metal sleeve for the camber bolts.

Later...shark era... service replacement.... dunno when, the holes in the bushings got larger, you mention 5/8".

The cure? Look in the catalogs and find the right bushings. You will need to burn out the rubber bushings in your current strut rods and then press in new bushings.

These new bushings have an outer metal "sleeve" as well as an inner sleeve. These new bushings will correct your problem.

"Been there, done that, got the tee shirt".

Chuck

PS: your bushings now have the rubber pressed directly into the hole in the strut rod. Your new bushings will have an outer metal ring. You will press that part into the strut rod.

JohnZ

Don't forget the hardened steel caps (photo in post #2 by Donny) - a pair of them goes on the end of each inboard strut rod bushing sleeve. If they're missing, the cams won't work.

donbayers

Don't know if this helps but I took pics of the new trailing arms for our 63.

biuliano

Chuck, thanks so much for the info. As a new member to the forum I am impressed with the quick response I got from everyone. Ecklers tech guy called me yesterday and came up with the same solution as you did.......kind of! He claims that the end caps will solve this issue. I have new struts with the 5/8 bushings already pressed into the strut rod. In your post you suggested buying new bushings and burning out the existing bushings. Is the tech guy off in left field yet again?

biuliano

A quick shout out to Donny, Dan, Chuck, John, and Don. Thanks for the help guys hope I can someday return the favor......said the mouse to the lion
Bob

Bill32

The forum vendors will have the small bushings.

I got mine for the 67 from Volunteer Vettes.

P/N SU 39 , Rear Strut Rod Bushing (small).

biuliano

Thanks Bill
I'm new to the site. What are forum venders and where can I find them?

Chuck Gongloff

You're welcome.

It's been more than several years since I dealt with your situation, and often times, I suffer CRS.

I do NOT think that using the correct end caps only will solve the problem. You have 1.5--2" of metal sleeve that goes through that rubber bushing.

I don't think that using the right sized end caps would compensate for that large a difference. My guess is that proper camber adjustment would be impossible, as the struts would be "wiggling" because of the discrepancy between the bolt size and the hole size.

I do not know if you can buy the struts with the correct bushings already in place. I would think that you could. I would look around at many of the forum vendors, Willcox, Corvette Central, Paragon, Keen Parts, Virginia Vettes, Volunteer Vettes, etc. etc. and see if they have what you need instead of replacing bushings in a brand new strut rod.

Chuck

Mike Ward

Chuck-

I know the outer diameter of the bushing changed as did the outer diameter of the strut rod end for later C3s ('75 through '80), but was not aware that the inner diameter and bolt had changed too.

The catalogues only list one part number bolt for '63-'82. (?)

Donny Brass

It's the crush of the bolt, not the bolt itself that holds the camber adjustment.....

the end caps fit the bolts, the bushings do not.

Chuck Gongloff

Yeah, that's where my confusion begins too, Mikey. As I posted earlier, I had a similar issue many moons ago.

IIRC, it's not the camber bolt, it's the ID of the metal sleeve within the rubber bushing...........

That is the issue that the original poster seems to have.

Chuck

Mike Ward

The '75-'79 strut rods have been sold a service replacements for '63-'74 cars for many many years. You'd think this issue would have popped up before.

biuliano

Spoke with Volunteer Vettes just a little while ago. These guys actually make the bushings and strut rods. They say exactly what Donny said in his above post. When I get the end caps in a couple of days I'll let you know if things go back together as promised.

JohnZ

It doesn't matter whether you have the larger diameter or smaller diameter strut rod ends and bushings - both designs use exactly the same cam bolt, end caps, cam washer, lockwasher, and nut. Neither the cam bolt diameter nor the lower shock mount diameter changed from '63-'79; only the O.D. of the bushing changed.

Pilot Dan

The OP's original post says " the cam bolts are 1/2 inch bolts and the strut rod holes that the cam bolts fit thru are 5/8" my take on that was the bolt hole was the problem and not the bushing (re-design) diameter. Am I missing something here??

67vetteal

Didn't the OEM Rods have Teeth that dug into the Washer for added strength/Holding Power? (It's been a long time). Al W.

Donny Brass

the "bolt hole" is not a bolt hole and is designed bigger than the bolt.

the bushing cap in my first post is the bolt hole, along with the bolt hole in the strut rod bracket and spindle support, the bushing itself is not dimensional to the bolt