H4 or 9003 is what the FJ uses. Very simple to change out too. Here's the link...
http://www.amazon.com/GE-9003NHP-BP2-Nighthawk-Headlight/dp/B006IPTOWQ/
I've used these GE Nighthawk bulbs in the past and they were very good and lasted well over a year. I've tried a lot of different and expensive European supplier H4 bulbs over the past 15 years. Many only lasted a few months, and poof.
Blue Coated Bulbs (like the GE Nighthawk Sport) cut the overall lighting output and will blind you in dense fog - Not Recommended. Always stick to clear glass bulbs for maximum output, like these GE Nighthawk Platinum bulbs.
I always order at least 3 bulbs at a time, and keep one spare in the glove box. This saves you from getting pulled over for a burned out headlight bulb, which can happen at anytime without warning.
It's a good idea to check your light bulbs once a year. Many high performance bulbs will turn cloudy or start to blister on the hot side, before they actually burn out. I had a pair of one year PIAA's that looked like mini volcanos on the sides, but they were still functioning.
