Leveling Jacks Do's and Don'ts

I usually use nothing, but it depends on the campsite and its substrate and also how level it is. I carry cut 2x12s also, enough to go under fronts, rears, and all 4 jacks. I have had to use them on multiple occasions. They are not cracked. I will use them to level on a sloping campsite, or if the ground is soft.

I position the RV, see how level or unlevel it is, adjust if needed, use blocks if needed. Once good, I engage the parking brake, and lower the front levelers, then the rear, then side to side as necessary. I don't have auto-level.