According to Diesel Power the 1500 EcoDiesel should be most at home on the highway.
Also of note they say that the Diesel is whisper quiet out on the highway...
Although I suppose a good chunk of that ability needs to be attributed to the 8 speed gearbox.On the highway is where the Ram 1500 with the EcoDiesel really excels. Power delivery from the 3.0L V-6 is extremely smooth and incredibly linear, accelerating briskly to well beyond the legal speed limit. While it doesn’t pack quite the same punch off the line as its Hemi-powered brethren (which, at 5.7L, is nearly twice the displacement of the VM V-6), passing is a nonissue thanks to the engine’s 420 lb-ft of torque.
Also of note they say that the Diesel is whisper quiet out on the highway...