Different front shackle years ?
 

I am replacing the shackles on the front leaf springs when I redo my springs in next couple of weeks.
But when ordering I have found conflicting info.
This is the 1956 Chevy 3200 project.

I see online some say 55-56 and 57-59 two different shackles and others say 55-59 some even say 47-59.

So the real question is are there specific differences between 55-56 and 57-59?

And a side note if you guys have a good spare set I might be buying.

Re: Different front shackle years ?
 

It looks like it supposed to be ACDelco 45G13044 (for 3200/3400/3600 models)
This one has 4 nuts two for each pin outside the shackle sides and no center bolt required.
(and of course out of stock everywhere)

The others are center bolt holding the whole thing together. No outside nuts. Which is the type currently on the truck. Still on the hunt if there is a difference in year models.

Re: Different front shackle years ?
 

I think the main difference might be price,

This is the filling station listing https://store.fillingstation.com/det...CKLE_ASSY.html

This is the Rock Auto listing where I believe you went along with a lot of folks who use it as much for parts number search as to order although they usually have the best price. https://www.rockauto.com/en/catalog/...g+shackle,7484

With the rock auto listing you can usually click on the part number and tell what all the part fits. In the case of that shackle a lot of GM vehicles over the years.

The O'Reilly's price is rediculously high https://www.oreillyauto.com/shop/b/c...hevrolet-truck

Re: Different front shackle years ?
 

You are correct Sir. RockAuto is my quick go to for part number lookup they are on target 90% percent of the time. Although I can often find it cheaper faster on other sites with shipping etc. But they have provided some good stuff to me.

What it is starting to look like is you can use either style on these trucks.
The nuts on side or the single center bolt holding the plates just a preference and price.

Re: Different front shackle years ?
 

just an opinion, the 4 half inch nuts give redundancy vs the single 1/4" bolt that can rust or break causing the shackle to remove itself.

Re: Different front shackle years ?
 

That is already in my thinking as well.
Some you can even add the center bolt for a extra step.

Re: Different front shackle years ?
 

A bolt with a sleeve between the shackle bars would act as a stiffener. I'm thinking that some aftermarket 4x4 shackles are done that way.

Re: Different front shackle years ?
 

The ones with the nuts on the end of the pin came out in 57. They were a much improvement over the earlier ones. They were listed as heavy duty replacements at one time.

George

Re: Different front shackle years ?
 

And I totally see why. Got under my 56 yesterday on one of the shackles has a 1/4 to 1/2 additional separation on one end where the plate has bent and it not against the bushing pin center next to bushing where it should be. Certainly explains the bang I hear every once in a while the last month or two. It was so packed with grease I didn't see it at first.

I ordered the 57 version and they will be going on when the springs arrive. (And I have free time in the cooler part of the day)

Re: Different front shackle years ?
 

There is a length difference in the 55 1st series and earlier as they had narrower leaf springs. Rock Auto and NAPA both sent me the longer versions when I ordered for my 54. One was even in a GM box.