so im sitting at a stop light the other day, at night(so the lights were on), and i was waiting to turn with my turn signal on, and every tim e the signal lit up, my volt guage would drop 1 or 2 volts, then back up, then back down. it would do this with every tick of the blinker. what i want to know is, is this any indicator of a bad alt. or battery without testing either one? it seems to work fine when plowing at night with the headlights on, and the amber rotors on. it just drops about 3-5 volts when i hit the pump on the plow. single 130amp alt. thanks guys!

Ken