Last Sunday we ran the boat for about 4 hours, put it on the lift and headed home. Yesterday, 6 days later, we got to the lake and the transmission fluid was low and there was a boatload of transmission fluid in the bilge. I've added about 6 ozs of fluid. I've drained the bilge, cleaned it out, wiped down the underside of the transmission, didn't find any residual fluid, and placed some doggie pee pads under the transmission. That was four hours ago and I don't see any drips on the pee pads.

Questions:
Is it possible to leak only when boat is in gear? If the answer is yes, where would the leak most likely be?

When do you measure the fluid in the transmission, does the boat have to been driven/put in gear? I measured it while it was still on the lift and before I even put it in the water.

I'm getting ready to take to boar out and see if it leaks while running?

Any help is appreciated.