Sudden grinding at ~70mph - torque converter?

[Bubblehead]

A little help on this one would be really appreciated, as I'm still really new to the 80s.

It's a 97 with about 225k on it. I bought it about 3 months ago with zero problems thus far.

Today I was in the fast lane of the interstate and went to pass a slowpoke going 10 miles under (60 in a 70) on the right since he wasn't budging.

When I stepped on it a little, I heard a grinding/buzzing noise.

Pulled it off the highway and it seemed fine but now it shows up during shifts, particularly with semi-aggressive acceleration.

Sound like the torque converter going bad to you guys? Entire transmission s***ting the bed?

Whatever it is, I know it ain't gonna be cheap.

 

[inkpot]

May be driveshaft bearings or slip yoke. Try greasing them real good and see if that makes any difference. John

 

[Kernal]

Does the grinding/buzzing shake the entire truck or does it feel like it's just somewhere in the front (axle)?? Maybe check the drive plates??

 

[Bubblehead]

No shaking. Sounds like it's coming from the front of the transmission but could be anywhere forward of driver's seat. I'll listen again and try to pinpoint the location in the morning.