Shackle question???
 

There appear to be two different types of shackles for the Chevy truck. My question is which is the right one for a 1/2 ton longbed and why the difference. The assembly manual has the shackle which bolts together with a single bolt through the middle of the shackle(the one on the left) . The stuff that came with the running gear I have does not have this bolt through the middle (the black ones) ???? Which one is correct ?? Or does it really even matter ???
Thanks

Re: Shackle question???
 

They are both 1/2 ton. The difference is in the year. 47-56 had the ones with no outer thread on the pin and a square in the center of the shackle for a bolt to go through and hold the shackle in place. 57 up had the outer threads on the pin and a nut held the shackles in place.
The cross bolts sometimes would either break or come loose and drop the shackle. I would use the ones with the threads on the outer end.

Re: Shackle question???
 

This info would have been handy to know a week ago. I just got four of the shackle kits from LMC Truck and they are the type with the bolt through the center and no threads on the pins. They are listed in the catalog as 55-59. I think I would have preferred the other kind but now that I have these I'll go ahead and use them. My truck won't see any heavy use so they should be OK. It currently has the other type.
BTW, LMC Truck ships fast. I had the parts in only a few days after I ordered them.

Re: Shackle question???
 

They will work ok. I would just use a grade 8 bolt and don't over tighten them. The originals were just carrage bolts maybe grade 5 or less.

Re: Shackle question???
 

Thanks dwcsr for getting back on this, and I held off on this question because I thought it might be a dumb question and must be totally obvious to everyone else but me:pty:

but your response makes total sense and was kinda of what I thought. It was just confusing based on the factory assembly manual. Now I can move forward with the assembly of the springs.

Re: Shackle question???
 

Thats one of the simple changes GM made in the Taskforce series. Most people think that all 55-57 frames are the same but each year has subtle differences such as the shackles and some brackets, radiator mount brackets, even the way the brake lines route changed over the 3 years.

Your project is looking good so far.

Re: Shackle question???
 

They will work just use a grade 8 bolt. Demensionaly they are correct.