Is This Enough Truck for 5th Wheel??

07 was the first year they put a DPF on the Cummins and they had some issues. You might suffer poor fuel economy and some emission codes. Many 07 owners do a delete (remove the smog stuff) and the engine comes alive and fuel usage greatly improves. The 4WD models had front end problems that were the subject of a recall. Make sure the truck isn't lifted as it probably won't fit your 5er and lowering it might cost a bunch. Welcome to the forum.