Private Pilot Flight Training and Instruction Flight Training Article Library | Back To 4VFR.COM WD-40 and Cleaning The use of WD-40 is not recommended on aircraft. It is not recommended because only a light lubricant is left after the solvents evaporate. Use Kroil or ACF-50 available through aircraft parts houses. The use of steam cleaning and pressure washers on aircraft is not good practice since lubrication points are not sealed. Open bushes, pivot points must be dismantled to grease. Pressure washes flush out the oil and will wet the interior making it subject to corrosion. Written by Gene Whitt Flight Training Article Library | Back To 4VFR.COM