Frozen levelers

If they are HWH jacks, the shafts can be cleaned and lubed. If they are the kick down jacks when she said they can't be retracted maybe she meant the shafts won't go back into the cylinder which is a common problem for those jacks, they can kick up, but the shaft is stuck extended. I have a left front jack that won't retract at times. I extend is slightly, then spray it with silicone or WD-40 and work the foot back and forth and the springs will then retract it fully. There is a seal inside that keeps the shaft lubricated once it is retracted. The shaft is SS so I doubt that they are badly rusted. Whenever I leave mine extended for an extended length of time, I have this problem. Once I do this procedure the jack is good for several years as long as I don't forget and leave it extended over the winter. The inner seal probably needs replacing because the jacks are 27 years old and I still have the original springs. If you can get the jacks to work by what I described that vintage Workhorse with 340 HP and the allision transmission is a nice combination. Good Luck.