Also you might not be getting a full 12.5 volts to the bulb. Something you might want to check. Our our Newmar, I had to put in a relay from the battery to get the needed voltage.
Just went out and check ours. The only thing I can find in my book is a MR16 which would not give off much light. Mine are seal beam and you could drive with them if legal for that. I think regular lights are wither 55 or maybe 65 watts. My driving lights are over 100 watts, and are set very close to the ground and the front of the RV. We have several DOT check points and they have a gauge to check them here.