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Howdy C2 owners.. I am re-building the back end of my 65 and ordered new leaf spring bolts c/w poly bushings.. To my surprise, the new bolts did not come with castle nuts and hole in bolt to secure them. ?? Is this normal with use of poly bushings? Also need to know the torque to use when assembling. Regards to all.. Dale
I wouldn't put poly anything on my kid's Radio Flyer red toy wagon....here is a pic of my poly trailing arm bushings from last summer - nice....
Anyway - you have to be wary of buying individual parts vs a "kit" for specific jobs.....the packaging of parts for "kits" varies..
You WANT the castle nut and cotter key - poly has nothing to do with it...
The springs apply constant (and considerable) pressure on the bushing and nut - you don't want it loosening up.
Here are midyear torque specs, I don't see a setting for the leaf spring bolts in there though:
Last edited by Frankie the Fink; Oct 29, 2018 at 08:42 AM.
Did they at least come with lock nuts? I have used longer bolts with lock nuts to lower the rear end before with no issues. I would order rubber bushings and stock type bolts if it were me, and I was using standard length bolts.
Some of the vendors sell a longer bolt and use a nut with a nylon end. The purpose of the nylon end is to lock the nut in place.So, no need for a castle nut and carter pin. There are no torque settings for the bolt. If you are using the longer bolt, just set it up so you are happy with the rear height of the body. Make sure both bolts show the same threads on both sides. Lastly, I would ditch the poly bushings. I replaced both sets on my 66 and 68 coupes because they turned to glass and fell apart. Jerry
I wouldn't put poly anything on my kid's Radio Flyer red toy wagon....
Anyway - you have to be wary of buying individual parts vs a "kit" for specific jobs.....the packaging of parts for "kits" varies..
You WANT the castle nut and cotter key - poly has nothing to do with it...
The springs apply constant (and considerable) pressure on the bushing and nut - you don't want it loosening up.
Here are midyear torque specs, I don't see a setting for the leaf spring bolts in there though:
Those nuts really aren't torqued. They're just tightened against the bushings. As the rear of the car goes up and down the spring end slides up and down with the change in spring curvature. I tighten until the bushing just starts to bulge slightly with weight on the rear wheels and then install the cotter pins. YMMV.
Last edited by 65GGvert; Oct 29, 2018 at 08:59 AM.
Did they at least come with lock nuts? I have used longer bolts with lock nuts to lower the rear end before with no issues. I would order rubber bushings and stock type bolts if it were me, and I was using standard length bolts.
They did not come with lock nuts, so will return and purchase rubber bushing along with proper bolt and castle nut as suggest by all who responded... After writing the post, I realized there can be no torque spec. Should have measured center space prior to removing... Next time.. I do appreciate your comments and recommendations, as I am new at this, not a mechanic, but always a DIY guy and love it.. Regards, Dale
They did not come with lock nuts, so will return and purchase rubber bushing along with proper bolt and castle nut as suggest by all who responded... After writing the post, I realized there can be no torque spec. Should have measured center space prior to removing... Next time.. I do appreciate your comments and recommendations, as I am new at this, not a mechanic, but always a DIY guy and love it.. Regards, Dale
The "correct" factory bolts and castle nuts have limited threads. Once cotter pin hole is centered within the castle nut opening there is maybe 2-3 threads adjustment possible. This is not enough to provide any meaningful benefit in suspension performance or stance.
And YES, by all means use the factory design RUBBER bushings. But buy from a quality supplier..........any one of our C2 forum sponsors is a good choice.
A last bit of advice - those springs can be a bit dangerous....I use a "C" clamp with a piece of wood abutting it with the bottle jack at the end and you have to make sure you aren't jacking up up the trailing arm if the car is on jack stands - making it unstable...
I ratchet strapped the trailing arm to my lift's ramps to do the deed.
They did not come with lock nuts, so will return and purchase rubber bushing along with proper bolt and castle nut as suggest by all who responded... After writing the post, I realized there can be no torque spec. Should have measured center space prior to removing... Next time.. I do appreciate your comments and recommendations, as I am new at this, not a mechanic, but always a DIY guy and love it.. Regards, Dale
If you are looking to lower the rear ride height, the better spring end bolts have fine thread with a pre-drilled hole for a cotter pin and employ nylon lock nuts. Fine thread is more resistant to vibration induced loosening, and the nylon nut insert is additional loosening prevention, with the cotter pin as the final safety measure to prevent loosening failure. The fine thread nyloc style nut can be adjusted anywhere on the threads and does not need to be backed into the cotter pin, not in the same manner that is required for a castle nut to be positioned to locate the cotter pin through the nut windows. The rear spring bolts, like all suspension hardware, should be visually inspected every few months for indications of change (in this case the nut should not be moving on the bolt threads). A high quality lowering bolt system will allow for height adjustment without compromising safety.
C2 leaf spring bolt
