The failure modes in the 60 and 60hd are very similar. Including sheared diff pins, second gear clutches, and OD lockup issues.

Yeah, this post was made out of curiosity. I haven't driven my car for a bit because of a slight whirring sound coming from my tranny, and also because it slips kicking down from 4th to 2nd. I didn't want to make a post in 92-99 because I know I don't have enough money to fix it, so I'd just be spinning my wheels. I'd like to think that Boosty is right, that it'* my pump, but we'll see. I think I'm gonna gather my courage and go drop the pan today. I just don't want to face the facts that my baby'* gonna be sitting for a while

All the things listed, including a pump are very internal. I would think it'* doubtful that the filter is clogged enough to stop the flow. If it is...then there'* other problems causing the material in the pan and filter.

Diagnosis isn't good on this one unfortunately.

Mine still shifted fine up until I got it rebuilt. The main issue was WOT, the tranny would grind and complain.

Mine has 1-2 and 2-3 slippage, 2nd gear slippage, shudder near shift points. Scantool showed all solenoids functional electrically. I drained the trans fluid and it showed MAJOR clutch material loss, and a few pieces of clutch material in the pan.

1995 riviera 4T60-HD

Lost overdrive lock up one year later losing thrid gear. Slippage on all gears.... Death