I am looking at moving into a 4500 series truck from my F-550. I tow a 18K 5'R and would like better stopping power. There appears to be quite a few 2007 custom 4500 series trucks brand new 0 miles on the market. Was there a problem with 2007 and do they have the power to tow my unit in the mountains, etc. Any advice would be appreciated. Thanks!

i have 07 5500 4x4, pretty much custom everything. No problems with it- the 07's have the lmm/lye duramax with emissions. Mine pulls ou 19,000 lbs fine. Its up FOR SALE NOW,
Making changes in life, and dont need it anymore. The new emissions and economy are probly why so many on dealers lots. The new emissions aren't that big a deal, the trucks are great.