Filled the Gray

Thanks all. Sounds like the consensus is fix it.

I would go back to dealer immediately.

also, if you 'work' on it, doesn't that void warranty and all that for future problems??

Take it back to the dealer somethings wrong!!

Mine did that when it was new. I found that when they drilled the hole through the floor, they kept going and hit the tank off center. Then straightened out the bit. It left a hole the size of the pilot bit just outside of the flange. A screw and some ABS glue and it was fixed. I didn't think it was worth the fuel to bring it to the dealer.

I'd get into the dealer. Some campgrounds might fine you for dripping waste tanks intentional or not.

Something has come apart; either the drain fitting or the vent pipe. Either way it is going to have to be repaired sooner or later. For the time being, drain your tank before it gets to the full point.

Waste tanks do NOT have overflows
Waste tanks should be able to be completely filled without spillage

Drain line from sink/shower and vent line go into tanks and are either 'fixed' in place by gluing them/fittings into/on tank or by means of a grommet/slip fit gasket.
Neither method should leak.

Fortunately it was grey that leak
BUT grey is still nasty
AND any leak into underbelly is not good......wet insulation, pooling of water in low spots etc.

Leak of any sort is not right or something one should ignore.