Rumble from tranny at 60

[Black95TD]

The other day I noticed for the first time a low rumble right at 60. No load. When I speed up to 65 most of it goes away. When I coast down I hear it until about 45 when the torque converter unlocks (at least thats what I think is happening at 45)

This is first I've noticed this. Have about 8500 on the clock now. Hope I'm not in for a problem. Several other posts a few weeks back about a harmonic/vibration at 60 but with a load of about 500 lbs.

Any thoughts on this would be greatly appreciated.

[Jim Brzozowski]

Note the exact position of the tach at 60 and try sitting still and taking the engine up to that same spot in park, you might find out its the exhaust system vibrating. Makes a kind of drum roll sound. Thats what I've heard.

[Black95TD]

SO - Thanks for the suggestion. I'll try that.