the exhaust doesnt have to be loose to rattle.

if any parts arent aligned exactly right they can rattle against things that they shouldnt be able to touch. this will occur under situations where the engine is developing full torque and is twisted on its mounts or perhaps under deceleration when it is laying over the other direction.

might look at your motor mounts too.

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.