Rear black tank flush

[Cdeez]

Hey errbody,
Boy have I got some questions fir some of you. That will wait for now though… here’s my question now. I have a _____ that has four tanks. 2 black. 2 grey. I have the black tank flush port and use it all the time. Thing is it doesn’t seem to do anything for my black tank in the back. Is there another system in place that I’m unaware of or how do people flush that rear black tank?
Thanks

[DQDick]

Folks who have two and don't have two flushes use an exterior flush that attaches to the sewer outlet or they do it the old fashioned way. Before flushes we just had to use a lot of water so that the tank drained, more or less, on it's own.

[Carl n Susan]

What year and model Montana do you have? Recent models do have two black tank flush fittings if the rig has two black tanks. There was a recent discussion here about this that I can't find right now. But here is a link to an earlier discussion.
https://www.montanaowners.com/forums...ad.php?t=83339
You can do a Search and find lots of discussion about the second black tank flush.