Need more info on which slide is crooked to be any help.
Different slides have different adjustments.
Is it a rack and pinion? They have two arms under the slide that run rhru the IBeam frame. There are adjustments on the arms under the slide to true it up. Need a couple wrenches and some time. Do a lookup on youtube for rv slide rack and pinion adjustments.
Is it an electric swinteck? They have tracks top and bottom both ends on the side panels. They have very little mechanical adjustment. You just make sure that you run them all the way in or out until they stop and hold the button for 4-5 seconds
Livin the dream... Retired!
TV 2016 F250 Crew Sterling Gray SB 6.7 PS airlift ultimate Air bags
2017 Eagle 321RSTS