Is anybody running 285's with the new 6 speed allison? I was wondeing if the tires would make the truck too high geared. Most of my driving is 50-60 mph. Don't know if it will shift between 5th and 6th gear too much. Would it be better on the transmision to go with 265's?

I run 285's on my 07'. It seems to shift into sixth around 55-60 under normal driving conditons. It does seem to shift a little more than it did but it's not that bad. If you are worried about it go with some 265's.

i havent had any probelms

No problem here, No need to worry about it anyways...

I have not had any problems at all with 285s on my 2007 Classic

I agree, no need to worry about it. I'm also running 285's.

no problem at all, and 80 is just a hair under 2,000 rpms. You will have to re-calibrate your speedo and antilock breaks.