I have a 01 rcsb chevy with the 4.8. My question is dose anyone know what rear end is in my truck, because when i research a set of 4.10 or 4.11 gears there are several options as far as how many splines are my axles and do i look at the 7.5 or the 8.5? This might be a stupid question but i just dont know i have never messed with a rear end before. Thanks for any help or input!!

 

8.6" with i think its 28 tooth spline or 30 not sure which and 10 bolt cover.