How can I disable IPv6? I have access to the IPv6 internet through Charter Communication's 6rd implementation. A number of CDNs fail to work correctly over IPv6, which causes a number of sites, including facebook, to have significant issues (pictures don't load, pages don't load, etc.)

On my desktop, I can disable IPv6, and these issues go away. Is it possible to do that on a stock android phone / tablet? (not rooted)

Edit: From the comments, I've learned that the actual issue is a MTU issue. So I'd be equally interested in a method to set a lower MTU on android as well.
Until Google does something about issue 1008, (which seems unlikely since it's about five years old now) you're unlikely to get a better answer, but for what it's worth, this might help someone in a similar situation.

At the moment you can't alter the MTU without root access to the device. In Linux this operation requires root, so on Android you either need to root the device, or Google needs to provide system functionality that applications can use to perform the operation (i.e. resolve issue 1008).

There is an off-market program MTUchanger which can be used on rooted devices to change the MTU. If you can root your device you can sideload this and work around the issue.

Of course, you should complain bitterly about Charter (and Rogers and the dozen or so other ISPs) deploying 6rd in 2013, when the rest of the world is moving past transition technologies and is doing native dual stack. 6rd is essentially ISP-private 6to4 tunnelling, which is why the MTU has to be lowered from 1500. As such, any company that deploys it is eventually going to have to do it again, and do it right.