That does not seem like normal operations to me. When I am not in cruise control mode, I am in either Low or High Engine Brake Mode. It is a rare moment when I am fully applying the brakes when the transmission is in "D" mode. And, I am not sure how braking system is tied into the leveling system.
With that said, my experience is the leveling works when air brakes are engaged and transmission in "N" mode.
When I first packed-up camp, I forgot to retract-all and placed the transmission in "D" mode; the leveling system immediately retracted...oops.
My fluid level is good (next to the generator).
Sorry hear of this issue. However, I look forward to hearing how this issue is resolved.
2016 Force HD
2016 Force HD 36