Questions of the era-appropriateness of the bionics technology aside, there's another problem with the use of the bionic arm. Even assuming it was capable of developing a ton of lift or more at the elbow and wrist joints, that still doesn't strengthen his shoulder and back similarly. In any of the type of situation where he used it to lift up the back of a vehicle or similar, all that would happen would be that the arm would draw his upper body
down with bionic strength - quite possibly smacking his face into whatever it was he was attempting to lift.
[Hindsight being 20/20, the era-appropriateness of the bionics technology is an unfair question, as the show is a 'near-future' construct, and we can't know exactly what the future will bring. As for the bionics-vs-human stresses, its a well-known fact that the human body is often capable of feats not considered possible by rational explanations. The TV series 'the Hulk' used the premise of super-human strength under duress as the reason for Banner's experiments. Non-bionic real humans have overturned cars with their bare hands in emergency situations. It's entirely possible this 'near-fture' bionic technology included something that tapped into such natural reserves, allowing Austin to use the arm at will, as seen.]
Corrected by John W Rosa
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