How much less weight sits on a Silverado's tires, compared to a Suburban?
Probably a fair amount more.... but traction bars and slicks combined with a stall converter and 1100+ lb ft of torque, is brutally harder on a axle assembly than even 900 extra pounds and a stock engine. The Gov-loc is the downfall of the GM 8.5/8.6 rearends.
I've built too many square bodies ( K5, K10 and Burb) with 10 bolts that never hurt and axle. Big block, small block, and yes even a 6.2 Detroit on a propane and nitrous mix and never hurt an 8.5....on reasonable size tires. Did have a buddy spin a one leg so hard it galled..galded? Stuck the spider gears to the carrier and was an occasional posi after that. But we are talking 3rd gear peg leg burnout till the cords were showing.
Hell Stapleton42 did a 8.5 with a Yukon diff in his turbo Yukon xl and didn't hurt it.
This was the big problem in my S-Blazer days, the Zr2 guys were grenading 8.5s with the 4.3 when wheeling. Not because of power, but because of the weak carriers.