16 389 glider with 12.7 no heat

I have a 2016 389 glider with 12.7 detroit that has no cab or bunk heat. The blend door is moving all the way. Only has 70 degree temp on the inlet and outlet hoses at the cab heater core. Lines at the engine are 150 degrees. Both shut off valves are open. Took off the lines and blew air through all the lines and both heater cores. Vacuum filled cooling system and pressure tested with no leaks. But still no heat. Lines are warm till about 1 ft from the engine then they are cool. Water pump possibly?

 

Engine temp is good, gets up to 170-180 and stays there. Has pressure in cooling system after running it. Both shut offs on the oil cooler and on the water pump are open and can blow air into them

 

Well so far I have bypassed the bunk heater system by running a hose off the cab heater core outlet to the water pump and swapped in a known good water pump. I have heat with the idle over 1000, but at a regular idle there is only like 80 degree air coming out. At high idle its over 120 degrees out of the vents

 

Swapped out the heater core out of a sister truck that is down and hooked back up the sleep lines and still had no heat. Almost less than with the sleeper bypassed so to me it seems like a flow issue. Checked the water pump that I took out and it seems to be just fine, along with the one I swapped in. The thermostats were replaced not that long ago by the customer. Can warm the the truck and watch the gauge and it hits 185 and they open up and temp drops down then comes right back up to 180. Only other thing in the system that hasn't been apart yet is the oil cooler, which joey said he had that before.

 

Was the oil cooler plugged and had problem flowing coolant out if it? Thats what im leaning towards as its the only part of the heater I haven't had apart yet.