There IS a anti-trans-drain thingy on the 1500 series rams. It's located
on or in the rad. That's all I know about it though. Maybe the Daks have it too.

 

It is always best to let it sit a second or so before just firing up and putting it in gear especially after sitting that long. I crank mine up and wait til the oil guage picks up good and then i put it in gear. Mine did that same thing in reverse before i started doing that.