Can you put prescription lenses into sunglasses frames? I have to get my eyes checked in about two weeks and I've gotten the use out of my current pair of glasses so I'm pushing to get new glasses. My friend was at the Oakley vault and he was sending me some pairs he thought I would like and I noticed that they looked like regular glasses just with sunglasses lenses and not only did they look good, they were cheap. Cheaper than the glasses my optometrist sells. So what I was thinking of doing was going up to the Oakley vault within the next two weeks, grab a pair, and ask the doctor if they could pop out the lenses and replace them with regular clear prescription lenses. Is this at all possible?

It may not be possible to fit the thicker prescription lenses into the thinner Oakley frames and have them stay there reliably. You will have to ask.

Having said that, prescription sunglass lenses are quite commonly made as you know, and you can also get the phototropic type that darken when outdoors (although that type will not darken down inside a car).

Yes it is possible.. Oakley makes RX lenses specifically for some of the frames. the previous poster makes some invalid points in terms of what you are talking about. Oakley makes many more frames than just "sporty" frames that fit tight to your head. Oakley glasses are held onto your head by the shape AND by the hydrophilic rubber pieces (called Unobatnium) in glasses that are less wrapped. You mentioned that these looked like Rx Frames / regular glasses frames. Please note, Oakley makes RX frames, as well.

If you go to Oakley's website and look under Rx Sunglasses, you'll see which can be made with prescription lenses, AND ones that you can have an Optometrist cut regular lenses to fit.

However, please note, many Opticians, have lab do their cutting work and some labs will NOT cut for an Oakley frame. If your eye doc allows you to take him a frame, then he should be able to have it cut. It depends on the lab. It may be easier to find a Optometrist with his won lab on site. Those are places that will custom cut.
Of course, if you, as the previous poster stated, do go with a very sunsglasses / sport model, you'll need to stick with the Oakley specific sport sunglasses lens as the lense curvature may be hard to match.