Worked on a 4L60E from a 2005 chevy truck with less than 100 miles today. A local company added a super charger to the truck for a dealer.
They tested the truck tooo hard before they delivered it back. They smoked the 2-4 band & drum , along with the 3/4 clutches. A common failure on stock 4L60E trannys behind supercharged LS1 motors in pickups , Avalanches, the Cadillac SUV's....
My point here is GM redesigned the front pump to case seal. It is now a press in lip seal on the main case. No square cut rubber seal in the pump body any longer.
The red color on case is the metal part of the new seal design. It is a stiff lip seal program similar to the style used on the filter to pump in the 4L60E trannys
second photo
