There is a 1978 GMC 1 ton that I should be able to get for a good price. I'm gonna check it out this weekend. Did these all come with a dana 60 and corp 14 bolt? Did the one tons come with a np205 or np203 (obviously I'll figure that out when I look at it, I'm just curious now). Any input on this model year truck? I'm assuming it's a stout old workhorse, that's what I want it to be.

If it is a one ton, it should have a Dana 60. Of course nothing says there wasn't an 8 lug 10 bolt or Dana 44 swapped in at any point.
And a 78 model should be an NP205

Some were available with the 203, but I can't remember the year split. That's where the fairly rare factory 60 slugs come from. :D

For '78, if it is an automatic, it is likely a 203.

This (http://www.chuckschevytruckpages.com/73-87specs.html) might help.

All the "correct" info and build codes are fine and CAN help......but we have a 30 year old truck here and some things may have been swapped out or changed. I understand the OP is curious now, and he is going to see it this w/e......and that should answer all his questions.

keep in mind there is a huge number of rednecks that call anything with eight lug nuts a one ton:shaking:

keep in mind there is a huge number of rednecks that call anything with eight lug nuts a one ton:shaking:

x2 drives me crazy

i just bought a 78 chevy 1 ton that is a 4-speed with a 203 and a small block. i havent seen a whole lot of those.