Just checking the rear end can be a pain in the rear end.
Mine we use ratchet, breaker bar, impact, and chatter gun.
It would not budge.
Got new one with cooper gasket from Mercedes.
18" breaker bar and 4' cheater pipe and 250 lb. and it finally let go.
Took old one out and with a few words of praise for the idiot that put that much pressure on it.
It should come out with a ratchet.
Good Luck
Charlie