i feel my truck it doesnt have the same power for couple days.it is 2004 lb 7 4x4.i got in august.i accelerate in lower gears but doesnt feel like before.i got a noise between 50and 60 miles from the drivetrain and then pass after 60. i only change the oil and the fuel filter 2 times. is got 111 000km.i use diesel from shel ultra diesel.i dont now what i have to do .maybe you give me some advice. maybe is just me i dont now how to drive this truck.is the first diesel i got.what sould i use for more power.thanks i lot guys