1961-1964 Buick and 1963-1970 Riviera Frame question

I know that Buick was late jumping on the Tubular-Center X frame bandwagon in 1961 when Cadillac started it in 1957 and Chevy and Pontiac picked it up in 1958 (Olds never used this design). Some say that the Buick version was beefier (stronger) than the other GM versions? If so, what makes them stronger? :confused:

Thanks
EricX

Never heard of that before. Where did you read this, Eric? I'd love to know the answer to that too if it's true.

If I remember correctly Buick started using the X-Frame in 1938 & didn't stop until 1970 with the Riv.