The Stovebolt Site Forums The Shop Area General Truck Talk Frames & Mechanicals - 1939 vs 1940 Chevy pickups?

I know the 1939 and 1940 Chevrolet 1/2 and 3/4 ton pickups look a lot alike. What I was wondering is what kind of mechanical changes happened between these two years?

thanks,
Doug

39 to 40 changed from spiral cut to hypoid gear differentials. 1940 are more like differential up through 1962. 1939 differentials are more like 1937-38.

Thanks for the post. I knew about the sealed beam headlights and the dash layout. How about the axles and hubs?

It looks like the frames have the same dimensions, but there is not a lot of information about '40s on the old Chevy Manuals online project website - many of the pages were missing or damaged when scanned in.
http://chevy.oldcarmanualproject.com/chevyresto/40index.htm

Any other big items that changed?

thanks,
Doug

check out the resto packs at Kieth's site, likely find all the differences there, if any - or check the same info from the horses mouth

Bill

AWESOME!!! Thanks for the GM library link, Bill!

This forum is GREAT!

Doug

Front axles and hubs are the same in 39 and 40. Rear axles are different reflective of the different differental. The two years have different splines on the rear axle. On 39 trucks, both axles (left and right) are the same length. On 40, one axle is a little longer than the other.