Is this normal?

We have a 2015 Cyclone, toyhauler.

I have to replace the toilet flange.

When I removed the broken flange, I found that the drain pipe was glued into the opening of the flange and not connected via the threads provided.

Plus, the drain pipe was not one piece. There was a gap, or about 4 inches, between the top of the pipe and the black tank. This gap is covers with a rubber sleeve.

Is the sleeve neccessary? Or can I use a single piece of pipe?

Any ideas?

This is not normal. The flange is glued to the top of the tank and the pipe is glued to the flange. The tanks are designed to be leak proof except for the vent. I went through this on my black tank as it had the same issue. Contact heartland, this is a dangerous situation that can cause health issues if it leaks into your camper.