TL, DR: 6.0L & 4.10 or 4.30 axle.
I’m not totally sure but I want enough to tow my work trailer when necessary.
If you are serious about towing anything near the weight of your '02 Tahoe, your axle ratio(s) should be 4.10, at least.
Anything HEAVIER, seriously consider 4.30. Your 4L60E go much farther between rebuilds with either of those ratios.
What axle ratio is yours presently?
If your truck accelerates enough now, to make you happy, look at the ratio between the weight of the truck and the power it produces.
Pay attention to the entire power band! It can be really frustrating if you do not.
If it doesn't make you smile -- and you want to smile -- figure out how much power that is going to take.
Once again, when happy, determine your power ratio.
Beg to differ here; let me explain.
Had a '94 Caprice wagon (LT1). With 2.56, top speed was 130MpH.
With 3.42, top speed and/or my courage exceeded 141MpH - and it took 3.42 less time to hit 141MpH than it took 2.56 to reach 130MpH.
Very roughly speaking, the axle upgrade from 2.56 to 3.42 was worth quite a bit of power
to the ground.
Sure, the upgrade from 3.42 to 4.10 or 4.30 won't be as steep as 2.56 to 3.42, but it's not just about engine power.
FYI, LT1 Caprices with 2.93 or 3.08 were rated to tow 5,000lb with the shifter locking out 4th gear in 'D'.
V4P Fleetwoods with 3.42 were rated to tow 7,000 in 'OD, all with the same LT1 5.7L V8.
Next, figure out how much weight the trailer has to it, fully loaded. With your existing ratio, you can get a ballpark for the power you will want.
Don't forget that your trailer will likely act as drag when towing it, so you might want to factor in a little extra OOMPH for that as well.
Once you know the power you want, look at how easy it is to get to that level with the 5.3L with forced induction, or the 6.0L.
Peruse the tow ratings of Suburhokonbalades with different engine and axle combos. Note how important the axle ratio is.
All that said, you'll get LOTS more bang for your buck out of a reasonably lower-mile 6.0L, than a huffnpuffn 5.3L - but superchargers are admittedly lots more fun-to-drive.
Either way, your engine will spend the vast majority of its time UNDER 3000RpM, especially since you are NOT interested in drag racing.
I still drive like an arsejack once in a while, but I don't remember the last time my engine saw 4,000RpM. Do you?
Don't forget the part played by gearing as well.