I'd stick with the 4.88's or do a 14sf swap when you do the 5.13's. The factory 10 bolt is weak enough by itself, add some 5.13's and 37's to that, and you know what happens. The pinion on my 4.88's was small as hell, and I bet the pinion on the 5.13's is rediculosly small. You'd prolly snap that pinion every time you took it offroad.
Honestly, the 4.88's with 35's is a bit over kill, now that I've spent some time getting used to them. If anyone is sticking with 35's I'd say just go to 4.56's and call her good! I love the torque and response with the 4.88's, trust me she'll s*** and get. If I baby her I can get 14-15 mpg city and about 12-13 mpg highway running 65 mph. Bump that up to 70 mph and turning dang near 2400 rpm's and the gas mileage ain't so pretty!
2002 Silverado 2500HD LB7 CCSB LT
EFI Live by Rob at ATP, Edge CTS Insight DSP 5 control, S&B CAI, PPE boost valve, Pro Fab AIH, AirDog II 165, PPE WIF sensor delete plug, 5" stainless exhaust, Cognito braces & HD tie rods, H2's 315/70 R17 BFG's
2004 Tahoe LT
2006 Silverado Z71 LS
1971 Chevy C10