Can seals cause shifting stall, when accelerating.

Hello, That is possible. The transmission fluid cooler is up front there, and I would certainly check the fluid level right away. Also, ensure you find which type of fluid is leaking, or have the vehicle inspected and repairs recommended. If you are leaking transmission fluid from the transmission fluid cooler, you may end up with a bad transmission. Since you have both symptoms and a leak, don't put this off.