I have a 97 Sonoma V4 five speed manual with 200k+. Runs like a charm, but I get a weird grinding/vibrating noise when the heater fan is on and I turn right. Only when I turn right, for some reason. Maybe the heater fan is dying? Except why only when I turn right? It does make the same noise occasionally when the fan starts, then goes away most of the time. Still, the right turn thing is odd. Any ideas? I know... it's a weird one.