One of the buying decisions I had to make on a new car a couple of years ago was whether or not to get a sunroof. Actually, it wasn't really a decision because it was pretty clear-cut; there's no point in having a sunroof in a car unless you want years of anguish and problems. In the case of my car, it was even clearer - it had the option of one of those full-length glass roofs with two opening segments - the worst possible combination.
I can understand why manufacturers still put them in though. They're perceived by the buying public as a luxury or nice-to-have feature. The glossy photos in the brochures and on the website look beautiful too because of all the light streaming in from above. But cut to the harsh reality of owning a car with a sunroof: it will leak. I've yet to find a manufacturer capable of building a sunroof that doesn't leak. It will be fine for the first few months of course, especially if you buy it in the summer. But as the weather begins to turn, you'll notice odd creaks and pops from the roof as everything twists and torques when you drive in the cold. Rubber seals will begin to shrink and perish, mechanisms will begin to stiffen and pretty soon you'll find yourself with the odd drip here or there where something won't close properly, or something else isn't sealing quite right. If you live in a snowy environment, there's not a sunroof in existence that can handle a few inches of melting snow sitting on its seals. And then begins the endless number of trips back to the dealer, where they'll never be able to find the problem, but will be able to accidentally unhook one of the drains meaning you'll now have a footwell full of water the next time it rains. Still - when summer comes around again you'll long forget the woes of the constant interior wetness. Now you have to deal with the burning heat of the sun shining into your mobile greenhouse. That's why most sunroofs have covers on the inside, which you'll close in the summer in a desperate attempt to keep the heat down.
In which case, you might as well have not bought a sunroof in the first place.
The salesman at the time I bought my car was mystified by my decision. He was absolutely confident that there was no way the roof would ever leak. After all this was a modern car! Take a look on the forums, go visit a workshop in the rainy season and see how many people are having trouble with leaking sunroofs and then tell me again what the benefits are.
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