I though our awning struts were weak until I changed the motor and roller cup assembly.

Our metal flex cover keeps the awning captured until the roller unravels a bit and once the awning is past this 'neural' position, those struts really take over with some opening force. 90 lbs of force comes to mind.
Anyway, you don't have to buy a new awning to get new gas struts. Does your awning come out without any help?
BTW, our Carefree has a strap that can help with the extension...never used ours, but it's there if need be.