I have a 2001 2500HD Crew Cab with the 8.1L and was wondering what the life of the shocks on these trucks normally are. I am debating whether to do it myself. Can anyone give me any advice on whether to try this or not?

Very easy to do by yourself. At least it was on my 1500, may be different on your 2500. I replaced mine at 100,000 mi.