[veryhuman]

Does the feature become a problem when you are waiting for tints to dry (2-3 days)?

[BloodShed]

It's true; this is only done on frameless door windows (such as most coupes). It started with higher class cars but is showing up on modern lower priced cars now.

Anyway, the main reason this feature is done is to deter theft. Because the window slides up into the frame when it closes, it seals the window. On frameless door windows that do not have this feature, it is possible to shove a wedge between the glass and the door frame. This could provide a few inches of gap to allow someone to disengage the door locks with a tool. Locksmiths often use this method on frameless windows.

Video of this:
http://www.expertvillage.com/video/2...tools-long.htm

[35past3]

Originally Posted by pokerface

easier to shut the doors as it relieves a bit of air pressure

LOL

[35past3]

Originally Posted by BloodShed

It's true; this is only done on frameless door windows (such as most coupes). It started with higher class cars but is showing up on modern lower priced cars now.

Anyway, the main reason this feature is done is to deter theft. Because the window slides up into the frame when it closes, it seals the window. On frameless door windows that do not have this feature, it is possible to shove a wedge between the glass and the door frame. This could provide a few inches of gap to allow someone to disengage the door locks with a tool. Locksmiths often use this method on frameless windows.

Video of this:
http://www.expertvillage.com/video/2...tools-long.htm

I disagree with you. The main reason for this is because if the window didn't lower it would keep rubbing the door seal, causing premature wear and tear. It has to raise into the door seal to form a tight bond to prevent excess cabin noise.

The feature has nothing to do with security. A thief will either cut the door seal or just break your window.

[BloodShed]

Originally Posted by 35past3

I disagree with you. The main reason for this is because if the window didn't lower it would keep rubbing the door seal, causing premature wear and tear. It has to raise into the door seal to form a tight bond to prevent excess cabin noise.

My previous car was a '92 Celica which had frameless door windows. I owned that car for about 9 years. It did not have indexed windows (this window sealing feature) and it never had wear on the seals. The way the seal works is the window is simply pressed against it. I'm not sure what "rubbing" you expect.

I would agree that cabin noise would be greatly helped. That's also part of the design. However, why would this feature bother sealing the window when the car is off? Cars without this feature are just as water-tight so there's no need unless the car is on. In fact, it might actually help the life of the window regulator (a common failure) if it only engaged when the car was turned on.

Anyway, there's plenty of benefits. I just had to comment because no one else mentioned it. If you don't agree/believe me, that's fine.

Originally Posted by 35past3

The feature has nothing to do with security. A thief will either cut the door seal or just break your window.

It's just a deterrent. There's always a way for a thief to get around it. The goal is to add enough obstacles that the thief no longer finds it worth the time/risk or moves onto another, easier target. Breaking glass tends to attract immediate attention. If they're stealing the car, those windows are also worth money. There's no point breaking the glass when it only takes 5-10 seconds insert a wedge and pop the locks silently.

[335xi]

Originally Posted by 35past3

I disagree with you. The main reason for this is because if the window didn't lower it would keep rubbing the door seal, causing premature wear and tear. It has to raise into the door seal to form a tight bond to prevent excess cabin noise.

The feature has nothing to do with security. A thief will either cut the door seal or just break your window.

Everyone is getting close but not quite there.

This started in high end cars with frameless windows. Originally frameless windows had only a pressure fit to seal the window against the rubber seal (the seal would only be on one side of the window). This did not work that well as the pressure fit was never perfect resulting in noise and potentially leaks, at high speed these windows tended to lift from the seal resulting in lots of noise. The better solution was to use the two sided rubber seal in framed windows, but the only way to do this was to lower the window a bit when it was opened and closed.

[mkaresh]

The last post finally got it. To put it a little more clearly, it's so you can have a seal that wraps all the way around the glass with frameless glass, forming an inverted U, just as you always have with framed glass. The older, cruder design is prone to air leaks and windnoise, and is much harder to properly adjust.

It has nothing to do with air pressure in the cabin, or they'd do the same with framed windows.