pro/con of 3/4 or 1 ton axle swap

[79rustyk10]

GM CORPORATE 14-BOLT
The "small" GM 14-bolt has a 9 1/2-inch ring gear diameter. It was used in the rear of 1964-and-later GM pickups, and in the rear of 1984-91 3/4-ton Suburbans.

Um... Ive never seen a SF 14 bolt in anything older than the mid 80's. Cant remember ever seeing one swapped in either.

 

[stumpjump]

Ramack, you need to decide what the goal of you rig is and pick you axles based on that. If you are running mild trails at slow speeds then your 10bolt will probably survive, if you want to hammer down it won't regardless of tire size.

My rig is built to run 40-42" tire but spends most of its life on 35s or 37's, even when wheeling. I built mine to go where I point it with no obvious weak points. I run a 350, sm465 and twin sticked 205- all beefy components to eliminate failure and a dana 60 and 14bolt combo with 1350 drive lines. My goal is to go out thrash and drive back without having to change shafts or repair a busted c clip axle.

Its all a matter of driving style and what you like to run. In the rocks dif clearance is crucial on mild trails it is less crucial but still important. Heavily rutted trails at a brisk pace will tax the ball joints of a 10bolt where a king pin is unaffected.

It all comes down to what your expectations and budget are. Build for your terrain and driving style and never look back.

 

[rgorsuch87]

I don't know about anyone else but I'm running 35's on my burb and I've busted not one but two 44's. I can't wait for winter to get here so I can get rid of that worthless 44 and 10 bolt. Just my 2 cents

 

[Blue85]

2.73 was a standard (and unfortunate) factory ratio. With 33" tires, you could easily go down to a 4.10 gear. This would reduce your crawling speed by about 50% and might save the large cost of the doubler. You really NEED to change gears anyway, so it's the logical place to start. For plans of only 35" tires, a 14B s/f is a good choice, especially if it means you can stay 6-lug and just throw gears up front. But if you are determined to go hardcore just put on whatever 8-lug axles you get a deal on with the right gear ratio.

 

[80' 427]

Ok I know I don't know anything but I would go 3/4 ton 10 or 44 front and a 14ff. This is only for a few simple reasons. Where I live you can bearly throw a dead cat without hitting a 3/4 ton 4x4 and they keep getting cheaper. They already have at least 3.73s and more than likely 4.10 and if your lucky 4.56s. Sure you can get buy with less but why spend any money on the 1/2ton axles? Yes the 14ff hangs low but you can get used parts for almost free. Do what you want but I sure wouldn't regear anything. I have done it and spent way more than I should have to end up with a locked and geared 1/2 ton.

 

[ramack]

I want to thank all of you for your input. Some things reinforced what I was thinking/planning to do, others gave me food for thought since I hadn't thought of all of my options.

So....

What I ended up doing after realizing that I had a 2.76 gear ratio and searching on Craig's List was a couple hours north of me I found a guy that was parting out a '76 3/4ton pickup with D44/14BFF hub to hub with 4.10s. I got them for a really really good price +tires/16"rims and the front driveshaft too.

I doubt if I'll have time to put them on the '79K5 within the next couple months, but that will give me time over the winter (yeah, snow already in the high country, so it's coming to the front range soon) I'll have time to think about my next options on how to lock the front and rear diffs.

I'll start another post for this.

Thanks again!

Rich