Sorry for reviving this old thread, but I lack the ability as a new user to start a new one. I recently purchased a 2014 4Runner Limited and I wanted to install a 2-channel dashcam. I selected the Blackvue 900S-2ch. As with any rear mount dashcam in the 4Runner, the sliding rear window does provide for an interesting hurdle to overcome.
There are a lot of innovative methods mentioned in this threat and others on how people have mounted there cameras and I thought it could be helpful for others if I added my solution to the mix.
I took inspiration from all that's been done before but I wanted to mount the cam in such a way that it looked through the portion of the window that's cleaned by the wiper.
More pictures of my install are available here:
Camera base - Album on Imgur
Anyone looking to print there own is welcome to download the files which I made available here:
4th & 5th Gen. 4Runner Rear Dashcam Mount by CasperSPT - Thingiverse