Have the above-noted truck. 67000K on it. 2 wheel drive, 4 litre V-6. Getting a couple of whiny "howls" lately when running (not idling). Took it to shop. They said the noise was my power-steering pump and it was starting to die. So I had it replaced but noises are the same. Kinda thought maybe it was the pinion gear but mechnic said gear was O.K. Is this an idiosyncracy of Mazda/Rangers?. Anybody have similar experience with these vehicles?

Can't remember if your truck has a fan clutch or not, but they can howl when they are wearing out. You can take the belt off for a short drive and see if it makes a difference.