With it hitched to truck drop the inner legs fully then spray the tubes with dry graphite lubricant. Then extend outer tubes fully and spray them
And as mentioned......glob of all purpose bearing grease can be added to top gears by popping cover of top of assembly
And while you have those outer tubes (driven part) fully extended........paint a red line 1" down from top. When lifting 5vr do not go beyond red line. You can damage gears/jack shaft etc. when fully extended under weight because landing gear will continue to run when reaching full travel until you let go of switch