Not familiar with the Blue Ox.
Watching the video on their website it says move locking lever to rear position. Apply trailer brakes and move truck forward. Does not suggest anything on hooking 5er.
Good Luck.
I have a B&W slider and there is no need to unhook 5er to slide the hitch. Just pull the lever and engage trailer brakes as well as chock wheels and pull forward slowly until it moves.
Dan & Patty
Miss Pickles the Pomeranian Princess Rainbow Bridge 8/8/2023
2020 GMC 3500 Sierra Denali 6.6 Duramax / Allison tranny
2021 Jayco Eagle 319MLOK
BWRVK 3710 companion
Maddy the Pampered Pom @ Rainbow Bridge 12-3-2013