I've got an 83 Suburban with 10 bolt front/rear and a 76 pickup with the D44/12 bolt setup. The D44 combo is running 3.73's, and I'm not really sure what the 'burb has, but it feels shitty. I was thinking 3.08's or something close. On the freeway, in the burb, 75mph is wide open on the primarys, but it's only turning around 2200-2300rpm. It's a TH350 and 33's BTW. It feels like it's putting a huge strain on the engine.

I was thinking of putting the D44 and 12Bolt under the burb. We don't really wheel the burb much anymore, in anticipation of my trail rig. This would give me the option of putting a 14BFF in the 76 and a D60(if $ allows) or an 8 lug D44. I'm not really sure what would be involved with the 10bolt f/r to D44/12bolt swap. It looks like they should just swap. I've heard the 10 bolt yoke will bolt on the 12 bolt, but I don't know what would be involved in the front.

If I'm not mistaken, if the burb has less than 3.73, I would have to change the carrier or use a spacer to run 4.10's. Is that correct?

Any other ideas? The burb is mostly a mom-mobile now, with the occasional trails, but it needs to be able to get out of it's own damn way.........

I'm already going to rebuild the motor/trans pretty soon, and give it a little more power (cam, etc), but something needs to happen with the gearing.

I have put a 14ff and 8 lug 10bolt in my blazer that were out of a
'burb, everything bolts up just fine. I would just do the axle swap, could be done in a day easily. 3.73's would give you much more rpm on the freeway so the motor would not work as hard.

The 44/12 Bolt combo will bolt right up without switching yokes. 3.73's would be a good choice for 33's. The 10 Bolts will take a 4.10's w/o a spacer.

Originally posted by rodzzilla
The 44/12 Bolt combo will bolt right up without switching yokes. 3.73's would be a good choice for 33's. The 10 Bolts will take a 4.10's w/o a spacer.

Will I have to mess with driveshaft length or any of that crap? It seems that the D44 and 10 bolt have a lot in common. I heard that you can swap everything from the knuckles out back and forth. Did GM totally rip off the design?

sounds like the axle swap will be worth it, especially if u put a 14 bolt and 60 in your truck. pull a rear diff cover off the burb to see what gears it has becasue if it has 373's then its not worth it,

Doing the math, it looks like the theSub has 2.73's. Swapping to 3.73's should make a big difference.