i found a 1987 1 ton doner vehicle for my k5 project....the seller is short on info at this time (older lady husband passed away...) and i'm not able to see the truck yet and i have questions. 1st what axle ratio did the diesels come with? What tranny-transfer case combo? and ratios? I know the front is a Dana 60 and the back a corp 14 bolt... Is the 1987 14 bolt a full floater? Also will the front 60 work when i want to go to cross over high mount steering? I think the spindles have to be a flat top type or somethin like that is that applicable for 87' Any info on this doner vehicle would be great.

1 ton will be a full float and with the diesel, probably 3.73. And you can get steering arms for the existing knuckles, both for x-over and high steer

Most 6.2 diesels (3/4-ton and heavier) got the 4.10s.

new knuckles are for 10b/d44. you dont need that for d60's.
it will most likely have a 400/208. you are going to ahve to move the spring plate mounts because they are different from 3/4ton and 1/2 ton.

My 3/4 4x4 diesel has 4.10's with a 14bff.

ive heard from more than a few dudes with the 3/4 ton diesel 4.10 axle package but i'm still wondering if the 1ton diesel stepped up the gearing again to a 4.56...i know GM put 4.56 in a package somewhere maybe the 454 1ton? also still looking for a low range gear number on the 208 and the first gear number on the th400... doin the math to find my crawl ratio with 39.5 tsl's.

Ok did some more research, answered my own questions. Just in case others were wondering here's the scoop.
87' GMC 1 ton diesel- 205 transfer case 1.94:1
th 400 tranny 2.48 1st gear
dana 60 front 4.10, 4.56 also possible
dana 70 rear 4.10, 4.56... not 100% on the rear here but the guide im reading says the K30 and the V30(duelie) had a 70. New question what is the 70 like for strength? ring gear dia.? axleshaft dia.? spline counts?

If it's auto it'd be a 400/205 unless it's a CUCV {military} then it would have a 400/208. It should have 4,10's. Our 86' 1ton 6.2/400/205 does. If it's SWR it will have a 14bolt,if it's a Cab and Chassis dually it will have a narrow
14bolt and if it's a dually that came with a bed it will have a D70HD. The
D70HD is stronger than a D60 but too wide unless you want to runn H1 double beadlock wheels.I think spline count is 35 but not positive.Never had one apart yet.

most of the 14b-d60 deisel combos i have seen are 4.56s! and the trany should be a t400 with a np208 or 205 but most likely a 208!

the d70 ring gear is 10.54. its a very strong axle. i think id rather have a d60/d70 combo over my 60/14b cuz the lowest you can get in a 14b is 5.13s, in a d70 its 7.17

My 87 GMC K3500 came with 6.2/400/205 and Dana 60 w/ 4.10 and 14blt FF