1/2 to 3/4 on 89 k5, do I need this?

[Phillip "flip" Stewart]

Newbie alert!

Alright fellas, my k5 is gonna be a weekend driver, I got a company truck for my daily. I jus got the k5 and I'm going thru it now. I hunt and plan to play a little in it. I need it solid because when it hits the road I plan on pulling my stock 82 4x4 in the shop for a lil tlc.
SOOO...... do I need the 3/4 axles? Or is there anything I need/can do to the 1/2 that's under the k5 now to toughened them up? I got a set of 37" military tires that I'm planning on mounting up. The k5 already has 6" lift under it.

We got some decent junkyards here in Bama and that's where I plan to snatched most my parts from.

Btw, the info/responses I've gotten already since becoming a member has been greatly appreciated !

 

[CK10]

To drive it on the street? The 10bolt will probably live if you treat it nice especially if it's an open carrier. If you want to take it off road you'll want at least the 14 bolt semi float.

You'll need to regear for those tires anyway, full floaters with a better gear set turn up for less than the price of the gears alone pretty often and lockers are cheap for a full floater. I run a semi float 14bolt with 33s because it was almost free and I could keep my 6 lug rally wheels. I'd ditch it in a second if I had to buy gears or a locker though.

 

[blazinzuk]

Front axle is fine on 37s as long as you don't put a locker up there. Even then won't be bad.

Rear axle on the other hand, well I just haven't had good luck with em.

So options.

Find a 6 lug semifloat 14 bolt ( 9.5" ring gear). You will need to change the perches and shock mounts and make sure the gearing matches the front axle.

Option 2. 8 lug 3/4 ton set with the same 9.5" 14b. Came in squares direct bolt in with a conversion u joint. The usual front axle will be a 10 bolt

Option 3. 3/4 ton axles with a full float 14 bolt (10.5" ring gear) these are 8 lug also. Often times you find a Dana 44 in a matching set but could be a 10 bolt too.

Any of those options will work well for what you need. Often when sourcing 3/4 ton axles you look for ones with 4.10s in em

 

[robster495]

I agree with blazinzuk on the options, the path I went was 8 lug 14bsf rear, matching 8 lug 10b front. I had 33's and I kept busting my six lug 10b rear (3.73s), so I trashed it. I've had a great time (multiple cross country road trips) with my 14bsf, but I'm about to make the switch to an AAM 11.5 ff

 

[paratrooper307]

You can get chromoly axles, but you'll be limited by the carrier.

If you're thinking about getting larger tires (and you will be at some point) it's cheaper to get 3/4 ton axles (commonly available with 4.10 gears) than it is to re-gear a marginal axle, and you get some extra strength.

My setup is an 8 lug 10 bolt up front and a 9.5 SF in the back with 4.10s. Gov-loc in the back and a lock-rite in the front. The setup works very nice with 33's and the ground clearance is a bit better than it would be with an FF. Picked up the set for $150, and probably through another 150 in bearings, seals, and brake parts to get everything up to snuff.

 

[obijuank5]

I did asphalt burnouts with 37s on my 28 spline 10 bolt rear with 4.56 gears and an auburn posi. Run em till they die.