1957 Napco GMC- junkyard rear end?

[Yewhi]

Trying to decide where to go with this. Below is the current rear end. Ignoring the rather spectacular red neck engineering, do you think that this is original?







It appears to be either a Dana 44 or spicer 45 which would've been correct but the backing plates appear to be wrong. I highly doubt this is original but would appreciate input as I don't know a ton about GMC trucks from this era.

If it isn't original or correct than my question is what next? My first impulse is to junk it rather than deal with undoing the 40 year old welding mess that comes with using it. I managed to pick up a chevy 10 bolt rear end for 125.00 that's in decent shape and would be a good option if I don't care too much about originality.



The only issue is the Dana/Spicer is geared 3.54:1 (based on the tag on the differential). I have not been able to locate 3.54 gears for the ten bolt. Assuming the Napco front is also geared 3.54:1 this could be an issue. So my second question is, does anyone make 3.54 gears for a ten bolt and if so where can I get them?

Thanks in advance!

[mongocanfly]

doesnt look like a 44...has removable 3rd member...can you find any numbers in the axle?

[dsraven]

I would say not original because of the shock bracket location. better make sure of the front axle ratio and condition before you spend money on the rear axle. try the site below for some possible info

http://chevy.oldcarmanualproject.com...esto/index.htm

[dsraven]

better check that rear wheel for straight as well, judging by the number of wheel weights.......

[Yewhi]

Originally Posted by dsraven

better check that rear wheel for straight as well, judging by the number of wheel weights.......

I know. . Check out the suspension blocks and that "custom" exhaust. The wheels are the least of my worries...

[dsraven]

ya, the exhaust would "self repair" but the brake hose would just melt off. as long as the front brakes work and you have a dual brake system and the hill isn't too long or too steep and the corner at the bottom isn't too sharp and...the.....uh oh.

[Yewhi]

Originally Posted by mongocanfly

doesnt look like a 44...has removable 3rd member...can you find any numbers in the axle?

No. Unfortunately there are no numbers aside from the tag that designates 3.54 gears. Possibly a spicer 45 which I believe was a precursor to the 44 and would've been stock on this truck. This is part of my confusion. There are details that fit and details that might not. I'm just not sure...

[G&R's57GMC]

On my '57 GMC Napco the rear axle is the same as the Chevy 1/2 ton with removable pumpkin.

On my '56 GMC Suburban Pickup ( Camieo ) GM used a Pontiac or Olds rear axle.

Here's the front NAPCO axle and 2 poor pic's of the rear axle.

I hope this helps.