Here's some clarification. 1/2-Tons came with a 3.90 as the standard
ratio, and these rear ends have a number of optional ratios still available.
Today, a 3.90 or 4.10 ratio is commonly considered "not so good" for you
1/2-Ton guys and gals. There are much better ratios out there for you.
Smokey was recently discussing a newly available 3.90 and 4.10 ring and
pinion set for the 3/4 and 1-Ton axles. The 3/4 and 1-Ton axle housings
have a much larger ring and pinion gear(in size) and will NOT accept a 1/2
ton set of ring and pinions. 1/2-Ton ring and pinions sets and 3/4 and
1-Ton ring and pinions are like apples and oranges. Very different!
My '59 1-Ton NAPCO 4x4 has stock 5.14:1 ring and pinions, and there was a
4.56:1 option available in '59. The 3/4-Tons came standard as 4.56:1 with a
5.14 optional. There was also an optional 4.10 and a 3.90 available for
both, but very very few were ever made. If you can find one, or have one of
these 3.90's, count your lucky stars!!! There have been NO 3:90 or 4.10
gears sets available for these trucks since the 60's.
Art Houser and Yvonne have worked with me and tolerated my rantings about
gears for a long time and have worked up a deal with a manufacturer to do a
limited run of 4.10 and 3.90 sets for these 3/4 and 1-Ton trucks. I posted
this several months ago when I first got the word. They will be available
in about a month and will sell for somewhere around $460.00 plus shipping.
Again, these are for 3/4 and 1-Ton GM corporate axles with drop out
differentials, HO-72 (1-ton) and HO-?? (3/4-Ton--Don't have that one
memorized, as I do own a 1-Ton. ---I think it's HO-55) Anyway, you 1/2-ton
guys are blessed when it comes to gear sets!! Trust me, I've heard the
slams some of you give the 3.90 ratio, given the availability of 3.38 ratios
for you. Well, a 3.90 for me would still be a godsend!!!! AND-- Hint,
Hint... If someone out there wants to make a 3.38 ratio for a 1-Ton, Why...
I'll take TWO, thank you!! :-)
Art Houser or Yvonne can be contacted at
Yours, Kevin P.
'59 Apache 38/NAPCO, Courtland, VA.
The NAPCO Owners Group
oletrucks is devoted to Chevy and GM trucks built between 1941 and 1959