someotherguy
Truly Awesome
You won't find 4.56 in any of the 9.5" 14 bolts, factory original, anyway. 3.73 is common, 4.10 less common, as is 3.42. Look into what it costs to regear both your differentials before choosing is the best advice I can offer there. It's pricey.According the the charts I'm finding, 4.56 gears are probably best for this setup. Are they common in the 9.5" 14 bolt or should I prepare to re-gear one?
RPO GU6 is 3.42, GT4 is 3.73, GT5 is 4.10. G80 is the locker option, Eaton Gov-Loc, which is notoriously weak in the 10 bolt variety, but reputed to be reasonably strong in the heavier 9.5" 14 bolt differential.
For proper width of axle you want a rear end from another 4WD. A RWD model will be too narrow. You can look at K1500 models if they have the RPO F44 which is the HD suspension; this includes the 9.5" 14 bolt; otherwise you're looking at "6 lug 2500's" also known as "light duty 2500" again only the 4WD models as the RWD axle is too narrow.
I saw someone else ask was there ever a 2500 Tahoe - nope. Don't think any ever came with F44 either. All of 'em 10 bolt 8.5" diff. There were diesel 1500 pickups which maybe? had the 9.5" and probably diesel 1500 Suburbans but finding one of those just sitting around is unlikely as they are very uncommon.
Richard