RB04Av

The reason for a newer style worm-gear carrier rather than a clutch style, has NOTHING WHATSOEVER to do with "mild" or "backlash on the spider gears" or any of the rest of that drivel. It's all about being just ... better. No grabbing, no chattering, no problems with spinning the inside wheel in very low-speed tight corners on a slick surface, just ... better. And of course, no clutches to wear out and require rebuilding.

I remember back when we used to throw stuff at our food as it ran by to get it to slow down long enough to take a bite. Started out with rocks butt we eventually figured out how to use long thin sharp pointy things. Seemed good enough at the time, we survived FWIW. Butt in the last few centuries I've noticed that supermarkets are actually a pretty damn good way to get food too despite being so new-fangled, and abuncha nostalgia for how good we had it back in the day doesn't seem quite so compelling anymore. Same deal with the carriers. We've learned a thing or 2, as a species, in the years since the clutch type was invented.

IIGW

i went from 3.42 right to 4.10

no reason to skimp and wish i went more gear.

Marky Dissod

How much more does a Tahoe 4WD Z71 weigh, compared to your Silverado 2WD RCSB? My Z71 has 3.73.
I'm accustomed to a mid-90s Caprice 9C1-LT1 with 3.73, and I've borrowed a GMT900 Tahoe PPV with aftermarket 4.10 several times.
I want 4.10 so very badly. Every time I floor my Z71, I'm disappointed.

If the vast majority of your miles are cruising in 4th on the highway, then 3.73 is understandable.
But that 4L60E will last longer with 4.10.

505-Silverado

Did you keep the factory tire size? Theoretically with the size I have now and 3.73 would bel like the OE Diameter and 4.10s. The diff was free and its bolt in I’m gonna install in a few days and see where I'm at.

My rcsb is 4200lbs without me in it. It moves pretty well as it is but the altitude at or drag strip is 5300 with DA around 8000. Is imagine the Tahoe being around 6k. Our 2008 Escalade esv was 6700

IIGW

my tires measure at 32 inches tall. Not sure how tall stock tires are

505-Silverado

Nice truck stock is about 31.

505-Silverado

Well I installed the 3.73 G80 rear axle this afternoon. I swapped my brake/components over (both were disc) since I had new hoses I took the opportunity to install them. New u bolts and fresh fluid.

Performance mods done so far,

E- fan and 34” radiator
LT catless Y and flowmaster dumped at axle
plugs, wires, fluids and filters
smaller tires
mild bench tune
corvette servo

BY FAR the best mod so far is the 3.73 gears. I’m not sure if it’s because of the altitude (5300’), weight (4,200lbs) or what, but the difference is substantial. So much so that I jacked the truck up after test driving and turn the pinion to make sure it was 3.73 and not a lower gear ratio.

Highway isn’t annoying and 2nd feels like 1st did with 3.42s over all stoked and couldn’t be happier. I kinda want to do 4.10 right away since these made such a difference.

Thank you all for the input. I’ll be going through the rear end later this year, updating the lsd, bearings/seals etc.

FWIW this truck would not break loose the rear tires to save my life unless it was wet now it’ll chirp on mild take off.

Edit
I’m not saying 3.73 is the be all end all gear ratio. It cost me nothing to do it but time and it was worth that. If I were at u pull it and seen a GT4/G80 for $150-$200 I’d buy it and swap it. But to order $500 gear set and pay $1k to have it installed I’d go for 4.10

Marky Dissod

4.10 will make you very happy, except possibly when you are lazily cruising along on the highway unladen trying to get the best possible MpG.
(I'm gonna put off 4.10 because I need to improve my suspension and steering first.)
Right now, it chirps on mild take off because your tires are undersized. With 4.10, bet you'll be able to chirp 265/65R18.

505-Silverado

I may have a 4l80 coming, with that the 3.73 will be about as low as I can go. .75 OD and 3.73 @75mph = 2500 rpm or so.

if I stay with the 4l60 I’ll definitely bump to 4.10

I’m not mpg focused but keeping it in mind. I’ll see how it does. These LS engines get decent economy even with the three speeds.

The whole goal of this truck is to have a factory reliable above average truck that I can daily and track once in a while. Focused more towards street than strip. Originally wanted N/A .5.3 stock with mild cam and tune, 4l60 and 4.10. If I get the 4l80 then it’s a sign that boost is in my future…..

1redta

I went from 3.73 to 3.42 with my 6.0 and am way happier