What part of MD are you in. I am in Linthicum / Brooklyn Park by BWI and working the same issue now. The noise you are hearing is most likely from a low fluid level. Top Hydraulics have excellent videos on their website explaining how to check the fluid level and remove the lift cylinders if leaking. Klaus at Top Hydraulics did a great video on the removal processes. I should have my main lift cylinders back from Top Hydraulic in a day or two.