Not at all...vast majority do their own...just don't expect the dealer to fix something that goes wrong as a result of your not doing it properly. There are lots of You Tube videos and tutorials showing you how to do it....really not that difficult, just that there is a sequence of sorts to follow....and tons of people on here to help guide you through it.
Also depending when you took delivery of your unit, chances are your warranty will be over by the time you take it out of storage next year...I have always said in my neck of the woods, a warranty is good for about 6 mths at best..we picked up our unit in early spring..it's now in storage and when it comes out next spring, warranty will be over. Unless of course you went for the extended warranty.
2011 GMC Sierra 2500HD
2014 Rockwood 8289WS, Diamond Pkg.