As OnTheGo said, be careful, I actually replaced the main cable in an old Jayco popup. The 2X4's will certainly work, just make sure they are all wedged in tight.
Keep us updated on what you find.
2013 Starcraft Travel Star 229TB
2011 Jayco X17Z(traded in)
2010 Jayco Jay Series 1207(traded for the 17Z)
2011 Chevrolet Silverado 2500HD Z71 CC 6.0L/3.73
Reese "Pro Series" 800lb Trunnion WDH w/sway control