Is this an indicator of something inside the muffler failing? I was revving the motor to make sure everything I had just done to it was ok - Under the hood was fine. Sat in the car, did it again - at about 23-2500 rpm I heard this raspy tinny sound I never heard before coming from the rear drivers side. I didn't touch anything on the exhaust.

Nothing seems to be hitting the exhaust. Using the mechanics stethoscope I didn't hear the noise on the exhaust manifolds but I did on the pipe. Seems to get louder as you go rearward. It's a dynomax super turbo if that makes a difference.

How old is the muffler?

Raspy tinny is a good description. My super turbo did that after 10 years on my truck.


The case rusted out in spots......

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Ed
64 Valiant 225 / 904 / 42:1 manual steering / 9" drum brakes

Oh... maybe 3-5 years? I haven't seen any rust on it. Raspy tinny is the best I could come up with... its a rasp but higher pitch, reminds me of a noise similar to when you would file a thick piece of aluminum.

It seems to only do it in park/neutral... Does that mean anything? I tried it in gear with my foot mashed on the brakes but it didn't.

3-5 years under a car is a bit more exposed than 10 years under a 4x4 truck bed..........


Get the car up on ramps and you can find it by running your hands along the pipes and muffler until you feel the exhaust....

The only good news is that super turbos do have a life-time warranty......

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Ed
64 Valiant 225 / 904 / 42:1 manual steering / 9" drum brakes

I get that raspy tinny noise when the internals of the muffler start to go.

My work truck was able to kill internal baffles in a year .........

If the baffle comes loose it can migrate to the outlet and block it off.

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Yeah....Im the one who destroyed this rare, vintage automobile.....