The "E4" refers to sway control device?
You do not need sway control unless you have a trailer that sways. Sway control is nice to have just in case, but
you certainly can tow any size trailer without sway control.
Make sure your ball is rated for that 11,000 lb trailer weight, some are not.
Sounds like your receiver hitch/towing set-up is ample for what you plan to tow.
The only question is will your truck self-level like many new trucks with tow packages. A 11,000 trailer will have 1,000-1.500 lbs of tongue weight so will cause the rear of truck to squat, then is when WD hitch helps, or if the truck itself can air up and level off.