I never change them unless they start leaking. The only ones I can remember changing were on my 74 240. I upgraded the fronts to 123 calipers and the position on the caliper was different. After a few months the new position cracked the brake lines and they started seeping.

My first expereince with brake hoses of significance was on the 37 chevy which I bought around 1971 which had sat in a field for years and had bullet holes in several locations. Those brake hoses were very rough looking and although I considered changing them I was just as thrifty back then as I am now and since they did not leak I ran them without issues until I sold it along.

Tom W

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.