How about a cyborg whose arm unscrews? Is he not augmented? Most of a cochlear implant can be removed. Nothing about trans-humanism says your augmentations have to be permanently attached to your body. You need only want to improve yourself and your abilities, which a robot suit of that caliber definitely accomplishes.

And, yes, obviously transhumanism is defined relative to historical context. If everyone's doing it, you don't need to have a word for it. That we have a word implies that transhumanists are looking ahead, and looking for things that not everyone has yet. So, no, your car doesn't make you a trans-humanist, but a robotic exoskeleton might be evidence of that philosophy.