The truck seems to stop better, but thats all subjective, I have no data to back up that statement.
A low rumble would seem to me to be a wheel bearing, which I feel like a number of people have had replaced early on in life. The way I diagnose this is to find two freeway exits/onramps, one that banks left and the other banking right. If the noise diminishes while turning left (putting pressure on right side of vehicle), its likely a bearing on the left side. Opposite if quiet while turning to the right.