Recently bought a 2003 f350 dump with a 6.0. has 40,000 miles on it. had about a 240 mile drive home from where i bought it and noticed if I had to go up any steep hills or get on the gas..once the rpms go up usually over 2,000 the turbo sounds like the engine has a rev limiter on it. "Figures"(rolling eyes) Truck sounds great at idle, no smoke, no check engine notices either. seems like turbo is releasing pressure and not holding boost. Im no diesel tech, any ideas fellas? THAnks!