Full floater ???
 

72 c20 I parted out has a 14b full floater from a later truck. I read somewhere that 1 ton 14b spring perches line up with our trucks so I am assuming this is a 1 ton axle. The drums are huge but the shock mounts are different. The previous owner I beleive said it had 307 gears. I'm not sure what it came out of. How do I tell for sure if this is a 1 ton and how do I check the actual gear ratio.

I also read here (I beleive Longhorn man stated), if I didn't misunderstand that all 3/4 tons (67-72) with a full floater and 350/350 engine combo had a 410 gear ratio is this true. My 72 GMC has a 10 bolt full floater. I beleive it is a Dana 60 (the cover is not round, looks similar to a dana 44 cover).

Question: if the 14 bolt is a 1 ton with the 307 gear ratio and non-posi, is it worth swapping it into my GMC (I have the drivelines as well from the donor) if it is a 410 ratio dana 60 (working condition). The e-brake cables seem to match.
What, if any, are the advantages? Disadvantages?

Thanks!

the 14 bolt is stronger than the D60 in just about every way, but if the D60 under your truck is doing fine then there is no need to swap it out.

What about the gear ratios. do the 14b come with that steep of a ratio and would that be preferrable or not on a not too daily driver. Would the a 410 Dana be stronger for towing than a 307 14 bolt? I just want to make sure i don't regret selling the 14 bolt.

Not that simple(67-72), the 2wd trucks are 42" from center to center, the 4wds are 40" and a 73 up one ton is 40.5". So if you have a 2wd truck w/ a 14 bolt that was not molested than it probably came back from 3/4 ton.

I'm confused, I've never heard of a Dana60 being called a 10 bolt full-floater?

It has 10 bolts holding on it's cover, but then again so does the H052.

The 14 bolt will have 3.73 gearing at the highest. If so it would be slightly better for you gas mileage wise but it is nothing you couldn't make up for with taller tires on your Dana60. To check the 14bolt just prop it up and spin one tire around while watching the yoke. the yoke will probably spin four times to one complete tire revolution. Almost all 14bolts had 4.10 gears you had to request 3.73.

Yup, the Dana 60 has 10 bolts on the cover & the ring gear! On the 14 bolt, I didnt know you could get one higher than a 3.42 gear(3.73 was the norm on a 3/4 ton truck)........69L

you can get 3.21's at the highest, and 5.13s at the lowest, for the 14 bolt. although the word on the block is that there are some 5.38's coming soon.

Jim...Are you saying the 73 up 3/4 ton 14 bolts were also 42" center to center. I am assuming you are talking about leaf spring perches, right? I guess I need to do more homework and crawl under there and do some measurements and count tire/axle turns. I'm almost certain the PO said this had 307 gears, but I guess from the answers here it is not possible.

If it is a 14 bolt 3.07s were NEVER an option. 3.21s are rare. 3.73, 4.10, and 4.56 are the most popular

Yep right at 42"

Oh, I wasn't disputing the actual bolt count..........just never heard it called that.
It just seemed funny..........Like refering to how many studs hold the center section in a 9" Furd. Why bother? It already has a common name?

I'm probably the only one that has called it that, lol. Not knowing what I have,
I was just describing it.

Jim, thanks for the clarification, I must have misunderstood what I read on a 4 wheeling board. I was searching 14 bolt and dana 60 info and nothing but 4wd forums pop up in my search. Now I know what I have.

Besides spring perch location, what is the difference between a 1T and 3/4T full floating axles?

In pre 72 vehicles and non-dana60 rear trucks the only difference is spring spacing and the size of the brakes.