Coolant leak from atop transmission?

Do you have a mirror, like a shaving/makeup mirror you can attach to something pole shaped to stick under the leak and see here its coming from without being directly under it? Mayb you can even stick your phone on video record that way?

 

Have you checked the bunk heater hoses?

 

I agree with that.

You should have valves on your engine to shut the bunk heater line off.

If you can't see anything I would try that and see if you still have a leak.

I would say maybe your transmission cooler is leaking or the lines to it but the lines for the bunk do run right through the frame.

 

Usually on the passenger side of the engine close to the firewall

 

I'm not sure about that engine but the valves probably could be on the top of the heads or they may be on the Block of the engine on the passenger side as said.

You should see lines coming in off of the frame on the passenger side. You should be able to tell which one is coming from the cab heater core and which one is coming from the back of the truck for the bunk. Follow them up to the engine.

You can shut them both off it won't bother anyting.

 

Check the cap on your expansion tank, I had one that dumped antifreeze all over the place.