While trying to figure out of there were any tricks to replace the low beam headlights in my 2003 Mazda 6s*, I was side tracked by reading about air filters. Since my air filter was about ready to be replaced, I decided to search the Internet for some information about which ones are better. I did find one scientific test, which (not surprisingly) showed that filters the block the most dirt, also restrict the air flow the most. Other web sites suggested (at least as far as paper air filters go) that the best air filter make and model will depend on the car and that you really need to just look at them and decide which one looks like it has the best design and filter area. That is what I’ll do when I go to the store and decide which one to purchase. Incidentally, during my search for air filters, I found an interesting oil filter study.
* There is no trick, but you need to have a lot of patience. Some fourms on the Internet claim that you have to take the front bumper off. The manual says you have to take it to the dealer. I did not have to go to the dealer or take the front bumper off, and was able to replace the lights. The only thing I ended up having to take off was the radiator overflow tank on the passenger side and the fuse box cover on the driver side. The passenger side was easier for two reasons. First, there is a little more room to maneuver the bulb and see once the radiator overflow tank is off; secondly, I already replaced the other one so I had some clue what I was doing. The thing that was odd about this was that both low beams burnt out at the same time. At first I was thinking something else was at fault, but the fuses and everything were OK, and it was indeed the case that the bulbs broke at the same time.