Rattle noise in the transmission. Sounds like a loose heat shield

[katoranger]

I had the car up on ramps to change the oil today. Started it up and got underneath. From down there I can tell that the noise is coming out of the flexplate area.

This is probably the case. I had a trailer hooked up that was loaded with produce and went over a dip in an unpaved parking lot. The noise started right after that.

Not sure how much work it will be to fix it. Still goes.

 

[katoranger]

I had a tip. Going to check the torque convertor bolts. They may be loose.

Car is still going.

 

[redmondjp]

I had a tip. Going to check the torque convertor bolts. They may be loose.

Car is still going.

The problem was already suggested above. You have a cracked flex plate. My 1988 Electra had this and it sounded exactly like a rattling exhaust heat shield (only made noise at certain engine speeds). I sold the car with the issue, at 221K miles.

 

[katoranger]

It is probably a cracked flexplate, but I can check those bolts without having to take anything apart. Been over a year and its still going.

Will report back after I check.

 

[G-721476]

Did you ever figure out what the noise was? I just bought a 1989 Oldsmobile 98 with 3800 engine pre-series one. Only got 81K miles and I have a similar rattle like you describe.