The main part of your lift system is the cable, or set of cables depending on the type of lift system you have. Almost every manufacturer used a different system, but quite a few used the Goshen System. That is an easy system once you figure it out.
For some good information about cable systems, check this link-
The most important maintenance for cables in a Goshen system is greasing them yearly. There is a long box under the pop up where the cables run through. This box should be greased yearly to keep the cables from becoming dry. There are 2 zerk fittings on the box, one on the bottom and one on the top. They are 90° zerks, the top one is hard to find. Fill the box until grease begins to ooze out of the fitting. This can take an entire tube of grease.
Had to replace our cable a couple years ago after it snapped while we were getting ready to set up camp. It's a Goshen system so pretty easy job, just greasy.
The system is basically 4 long springs that run up through each corner in the lift post. The springs are pulled by the cable, as you crank the roof up the cable pulls the springs through the tubes to raise the roof. Each lift post removes at each corner and drops down to remove the spring.
The cable runs through a long box under the pop up. This box should be greased yearly to keep the cables from becoming dry.
I used this guys pictures and description to attack my cable replacement. I ordered the cable from Goshen Stamping, and it came cut to length and with the clasps in place. They also sent directions with the cable.
The winch access door to crank up
The winch accessed through the back storage compartment and wall removed