[technocat]

From what the manual says, the front turn signal bulbs are supposed to be a P21/5W, which is a bulb number 7528 in the Sylvania brand...it is 5W low beam and 21W bright beam. Using any other wattage will result in irregular flash. (Same bulb for the brake/tail light)

The rear turn signals are a P21 bulb, or 7506 in the Sylvania line. This is a single 21Watt bulb. I've used standard Sylvania Long Life (red packaged) automotive bulbs and they work forever.