Napco/'57-'59 Chevy/GMC truck front axle pics

[Longbox55]

https://plus.google.com/photos/110211271593344394189/albums/6118796364340577121

Edit: After some further research, the axle shown is for an Advance Design '47-'55 1rst truck. However, other than the center section being on the left instead of the right (except for some early '55 2nd 1/2 tons), the axle assembly is the same as the '55 2nd through '59 Task Force trucks.

Edited March 4, 2015 by Longbox55

[southpier]

helpful pictures but of course questions are always waiting....

Q1. - i get how the ball end gadget allows the wheel to steer, but what (internal workings) allows power transmission?

Q2. - what advantage (except housing the mechanicals) does the oversized hub contribute? this might be better directed to a stock car (2wd) front end.

thanks

[Longbox55]

Q1; There's a Rzeppa style constant velocity joint inside the ball housing, same type of joint used for the outer joint on todays halfshafts found on most fwd cars and IFS 4x4 trucks. Otherwise, the shafts inside are the same as what you would find in any other 4x4 solid axle. The Rzeppa style joint allows for smoother power transfer over a Spicer style joint.

Q2; The actual hub itself isn't quite as long as it appears in the pix. Most of the length is for the spindle and bearings, which are the same as the rear full float axle. The additional length is for the aftermarket locking hubs, No real advantage, just simply the size they needed to house the components. Most newer solid axle trucks have gone to a center disconnect in place of locking hubs, plus sealed type bearings, so they do not have the extra length.

[southpier]

i may have to ponder that a bit before it sinks in, but you've given me food for thought - thanks

[Longbox55]

Here's a cutaway pic I scanned from the manual, this will show it better.

[southpier]

makes much more sense now; thanks again.

[Longbox55]

Could be worse, there's several different styles of joints that were used back then, with the American-Coleman being the oddest of the bunch.

[Longbox55]

https://youtu.be/e-4A5pFbuLU An old promotional video from 1957. Towards the end of the video, there's a few good shots of the chassis/drivetrain.

[southpier]

that's wild. love the "butterscotch" paint jobs.