We replaced our electric levelers with the BigFoot hydraulic levelers. One major drawback: There is NO manual override should one of the BigFoot hydraulic jacks fail. Recently we had one of the front jacks fail to retract and we could not move the trailer in that condition. I called the BigFoot 24 hour tech line and they diagnosed a pump failure. To raise the jack for travel we had to bleed 64 ounces of ATF fluid (what a mess!) and obtain a floor jack to raise the failed jack. I understand that there are some hydraulic jack systems that do have a manual override.