I am really surprised this didn't kick up

Of all the Uncle Tony videos, this one is the only one that I disagree with.
I seriously doubt that any engineer would purposely design their cars to flex. These cars were built to last a few years and be replaced. The tires of the day were narrow and slippery compared to what is available today so the chassis did not flex much then anyway.
I'd bet that very few people ever thought these cars would be collected and restored 50-60 years later. They were people movers, not investments.
Even fewer would have ever imagined that tire science would improve so much.
I have heard his theory shared before and I can see his point, I just don't agree with it.
Chrysler built these cars to meet the standards of the day and to compete against GM and Ford. ALL companies have the capability to make a car that is virtually indestructible but the costs to do so would be astronomical. They could have made the chassis as stiff as new cars are today but to what point? The market tolerated what they were sold, not many people demanded better.
In every case that I have seen, subframe connectors increased stiffness and cut down on squeaks and rattles. In my '70 Charger, it took road bumps and imperfections much better than without the connectors. The car soaks up bad roads and feels solid. It may even ride better because the car isn't skipping or rebounding from bad roads.

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