Can anyone identify this horrendous rattling noise?


G-Body Guru
Oct 29, 2010
Buffalo, NY
'85 Monte

SBC, 200r4 with column shift.

It just started one day. Goes away occasionally but has gotten worse. I thought it was the column shift link bar because it touches the headers but I can use a screwdriver to move the shift link away from the headers and it still does it. Does it while driving too. Mostly while accellerating 0-40ish, after that it seems to settle. Any help would be appreciated.



Master Mechanic
Apr 28, 2016
Ima take a wild stab at this and say..... muffler bearings. j/k

I've had this noise before and it tuned out to be a cracked flexplate for me.... but could be loose convertor bolts as well.
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Master Mechanic
Apr 25, 2020
Ocean County, NJ
Going to take a wilder guess and say broken catalytic converter internals.
Mine was making the same sound. Was broken honeycomb inside one of the cats…get a piece of rubber hose and with it running place one end right next to the cat and other end next to your ear to try to isolate the sound location
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Master Mechanic
Jul 29, 2008
if a flex plate is cracked while the engine is running and in park rock the car aggressively front to back while doing so listen carefully is the sound progressives or not
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