Big Country sewer system schematic

Thanks Tim. I was thinking he meant they went to the same tank.
Wonder if this is something I should be concerned with. Although I have never had this problem yet.

Found problem. Was able to run sewer snake up to black tank and got it flowing. Thanks everyone. Ron

We do not have drain a schematic. We had a similar problem with our 2014 Big Country 3070RE. Seemed to be at the point where the drain lines come together after exiting the tanks. Kept working at it with fresh water hooked to the flush tank valve and poking a small branch up the drain line a couple of feet. Finally got it cleared. We now carry a regular 15 foot drain rooter cable in case it happens again. We minimize the paper we use by using the community toilets where we stay. Also once or twice a day we fill the toilet to the rim using the half engagement feature of the flush pedal to send a surge of water through the black tank to purge it. To "mud maker" the lines merge after leaving the tanks... the tanks are separate.

If I read right, you have a 90 gal gray which is probably the shower and kitchen sink. The 45 gal black tank is probably your bathroom sink (aids dilution) and toilet. I'd start with pulling the shower drain and look in that trap 1st. Is the kitchen sink draining properly? Blockage where the shower connects into the sink drain line is probably not as common unless there is a sharp bend. I went to Heartland site and did not see a diagram for the plumbing (just flush system and heated pads)but I suspect the different Heartland models are plumbed similar based on floor plan. Since the kitchen sink and shower share a common wall it makes sense to use a common gray tank. Hope that helps.

Go to the Heartland Owners forum. They have many online manuals available.

The shower and the toilet drain into the same tank? Interesting.
I figured the shower went into a grey tank and toilet had its own.