Has it had a lot of water pooled in it or maybe it is just somewhat old.
Awning spring tension.
Dometic sells a tool to assist with winding the spring but you can do it using.
This is a quick and easy fix that requires just a few.
When you release the tension in the spring the cotter pin that is inserted in the holes in the awning arms are removed.
Changing the tension on manual rather than electric patio awnings with standard support arms is relatively simple but the job is made easier with an extra set of hands.
It might be time to adjust the tension.
The spring is prewound in a direction that places the awning under tension when retracted and then tensions further as the awning is deployed.
Remove the bolt that holds the end cap to the awning arm lift the awning and end cap out of the awning arm while a helper supports the awning and rotate the vice grips to relieve the tension of the spring noting how many turns it takes to do this.
12 turns 19 ft up 13 turns.
Has your rv awning been sagging.
Rv awning tension adjustment.
If the support arms that hold the roller bar are attached to the side of the rv or trailer find the screws that hold them in place and unscrew them.
In most cases readjusting the tension in the springs solves the problem.
The cotter pins are the ones that lock the spring tension securely while taking down the rv awning.
Does it struggle to roll up tightly or straight.
After a few years or sooner if your awning sees heavy use your rv awning may start to look a little limp or saggy.