I am getting my new GMC duramax 4x4 crew cab 2500 standard bed in June, when incentives get a little better I hope, but i want to put new rims and tires on right away. I want 285 75 16's with weld super single II 16x8 or 9's. Can someone tell me if either of these combinations will fit without lifting or trimming. I do not want to lift it. Thanks in advance. And by the way great site, I am a newbie to the site and diesels.

They'll fit but they will rub when steering wheel is all the way over. maybe a bit before that too.
You can raise it by cranking up the torsion bars.
Check the offsets on the rims, stocks are 4.5", you'll want to stay around that size.

Thanks NOREASTER thats exactly what I was looking for. If anyone else has anything to add that would be great, looking for any alternatives. Thanks guys.

I did the 16X8" weld 258 sidewinder 4.625" offset. Wrapped them with 285's and couldn't leave discount tire, they wouldn't turn past the bumper on my truck. The guy who was mounting my tires had just graduated from a body shop school so out comes the angle grinder on my new truck, I think everyone was worried but him and I. We cut off literally just enough to make it happen and it looks pretty good IMO. You almost have to be looking for it to see the missing plastic. Besides that they do rub on the driverside wheel well liner on a full lock maneuver.

These things could probably be fixed with a T-bar crank which I keep thinking of doing just haven't done it yet. Good luck and go with the 285's on the welds, you will love them!! :grd:

Edit: check my truck pics, one of them shows what we had to cut.

just get that cognito leveling kit, its only 495. That way you can have some tires that are actually worthy of your truck. A huge truck like that looks like $h!t with little 245's. My 285 look great on mine