I would like to know a couple of things about the 9007 bulbs used on my '93 F150. First is , what is the difference between a 9007 and a 9004 for instance. Next, are the "cool blue" G.E bulbs any good or better than a normal 9007 bulb. And finally, what is the thing with the Piia bulbs? why are the so very expensive ($114.00cdn a pair)and are they really that much better than a "cool blue" bulb? I just changed my bulbs out for the cool blue type. Perhaps I should have used a xenon bulb instead. I haven't driven at night yet to see if there is any difference. My original bulbs were turning black and I figured they were loosing some output. What is the purpose of the blue, I know that the new European and Japanese high line cars have a different type of lighting system that have a very blue light which is really distracting in a snowstorm to oncomming traffic.

 

The "blue" bulbs are a "fashion statement".

Expensive cars come with HID lamps now, which are a new type of lamp which puts an electric arc through a capsule filled with xenon gas. There's no filament and an external box called a ballast is used to trigger the lamp with a high-voltage spark to get it started. They have a distinctive appearance, with a very crisp white light due to xenon's even spectrum of light, similar to sunlight. They look kind of bluish in comparison to regular halogen lamps.

HID lamps are expensive, so anyone wanting to be fashionable either has to shell out $500 (us) or resort to a wanna-be imitation - the blue-tinted bulbs.

The blue-tints are a waste of money, look stupid and in many cases are not highway legal. They are often 100 watt bulbs, since the blue tint restricts light output and they up the filament rating to get enough light to see by. High-wattage bulbs can damage the wiring in your vehicle too. Beware the "off-road" use only markings too. Unless you are driving off road.

If you want to upgrade your bulbs, just get a regular brand name bulb like GE, Sylvania etc, that's highway legal, DOT approved. GE offers regular lamps and high-output lamps along with a legal blue bulb. (I've bought the GE HO lamps at WalMart and they are pretty good.) Sylvania offers several models of lamps, high-output and the "silverstar" line. All highway legal stuff that won't burn up your wiring.

Usually, a lamp that's the same wattage but produces more light will not last as long. The candle that burns twice as bright burns half as long afterall.

Finally, Sylvania DOES offer the only highway legal HID replacements for regular halogen lamps in their Xenarc line. They aren't cheap, but they are the real thing, legal in all states (Canada too probably) and in most case plug and play.

 

The 9004 lights are 50watts and the 9007 are 55watts. The PIAA lights burn 1500 on a sun light scale and the cool blue burn 1300 and the new ones by sylvania burn 1450. PIAA makes DOT-Legal bulbs I have a piar and they do not light up blue they light up a very white light.