I have a 3" body lift with leveling kit on mine, and with 305/65-17 32.6x12 measures closer to 33x12, I only rub a tiny bit on my mud flap when extreme off roading. 35's should fit for street driving with a little trimming but it would be extremly close!!!!

 

Your best bet is to just do a small body lift. However I've seen several Cadillacs and Denalis running suspension lifts. If you get a full drop (non-knuckle) lift with proper drive-shafts, you should be fine. I know there was a member on GMFS running the Rancho lift on his Yukon Denali.

 

I have a set of 17x8 rims. will the 35x12.5 fit these or will I need a wider rim?

 

they'll fit easily.

 

x2, no problem at all.