Miata headlight bulbs not burning the midnight oil - why?

Thanks for all the brainstorming. A few posts have asked questions, so here are some answers. - The only other bulb to go out is on the dashboard (and if anyone knows how to replace that, I'd love to hear how -- and oddly two of the three bulbs in my husband's Mazda's dash have also gone out). - The car is ten years old, and the problem has been happening the whole ten years, so I don't think it's corrosion. - It has happened in the three very different places I've lived with the car, so I don't think it's the roads. - It only has 70,000 miles on it, so I don't think it's from having them on excessively (although I do drive with my lights on most of the time). - They don't both go out at the same time, so I am kind of guessing that it's not a voltage issue, but as my husband will readily tell you (with disdain) I managed to get through undergraduate and graduate school in the sciences without ever taking physics, so I could be wrong there. - There's a lot of rain where I live, in the Pacific Northwest, but I've never seen water in the headlight casings, and haven't noticed any rain-related patterns of dead bulbs. It seems like I'm getting down to poor mounting (and hence physical trauma to the sensitive little dears) or karma payback for something I said to an ex-boyfriend at some point which wasn't entirely deserved. Maybe the time Mike berated me for treating him like a child, and I calmly pointed out that his shirt was on backwards? No, I think that was deserved...must have been something else.

@ Big_B, et al - yes, it was a 2003 Protege 5... Sorry for the typo!

I don't know if this is a general Mazda trait, but my friend and I had matching 2005 Mazda Protege hatchbacks for a while, and our headlights burned out every 6-9 months. It was crazy, but we both got crazy good at replacing them (especially in winter). I think this is either a 2002 or 2003 because they only made the hatchback for two years (the Protege5). Either way I was going to post this same anecdote. Our 2003 Protege5 goes through bulbs pretty fast, and if you check some of the mazda/protege forums it is a known problem. They are very easy to change after the first couple of times. No tools are needed.

My 2000 Miata never went through bulbs like this.

My 99 Miata didn't like the expensive sylvania bulbs, which burned out quickly too. My cheapo replacements have been just fine, though most of my driving is daytime without them on. You really should check miata.net as there are numerous posts on lighting. Good luck.

I never touch the glass on the bulbs, and I've shaken the housings and they don't move. I just don't get it. I'll look into the HID option. Thanks.

It sounds like it's a vibration issue with this car vibrating the bulbs so much that they fail. You could try opening the hood and wiggling the headlights to see if the mounts are loose. I live in the Northwest, and I saw a local mechanic advertising High Intensity Discharge headlight conversions for most cars from $150. Maybe, just maybe, HID headlights might be more tolerant of vibration than regular bulbs.

If you get the oil from your fingers on the halogen bulbs when you change them, their life span will be shortened.

There don't appear to be http://www.miata.net/garage/tsb/ on overheating bulbs. I have a '96 but that's a NA model (pop-up headlights instead of integrated) but I can attest to the build quality of the Miata in general. You probably know this already but if the bulbs are touched at all it can negatively affect their lifespan dramatically.