TurboS10

iTrader: (12)

05 Yukon, 260k+ on trans, I bought it w/150k on it and I think it got rebuilt previously. The case is painted.
On shifts or light throttle when cold, it makes a light ringing sound. Like the PR or AFL valve is cycling. It's a continuous noise in D3. If I let off the throttle is will go away. Not super loud. But my old tinnitus ears can hear it with the stereo off. I drive 80mi a day. It shifts perfect. One of these days I'll remember to turn the stereo off when I get stuck in traffic to see if it does it when hot.

FranksCustomTrans

I had a guy a few years ago he said it was a metallic buzzing sound. We tracked it down to the pressure control solenoid. He replaced it and noise gone. description same as you give.

TurboS10

iTrader: (12)

Thanks Frank, I'll add it to my next Rock order.
And thanks for the tip on the stove heating of the input shaft for removal. I was a little worried about galling on removal.
I've got an 06 4wd trans 200k+ from a truck I parted out for the S10 swap that will probably need resealed.