Cosmoline & Underbody Wax Removal

by Jeremy Goodspeed

Cosmoline also known as body wax is a soft yellow material that is applied by both European and Japanese autoCosmoline Removal manufactures. This product is designed to protect the vehicles during transport to their destination. Although Japanese manufactures usually confine this application to door jambs and hood hinges, European manufactures will coat the entire underbody and motor to protect aluminum and steel components from corrosion during shipping. Although this has been common practice for years, this yellow material will attract dirt, and become hard to the touch as it becomes heat cycled with normal vehicle operation. In time, areas such as water jackets and valve covers will become permeated and be forever discolored.

Removal can be as involved as you are willing to go. Some owners are only concerned with fender wells and other directly visible areas, while others want it removed form every component including the transmission casing. Both new and older vehicles can benefit from cosmoline removal, however be aware that cosmoline will be more difficult to remove on an older vehicle and sometimes will have cosmoline residue that will not be completely removable.

The first step in removing the cosmoline is to evaluate your vehicles needs and determine how far you are willing to go to remove this material. For removing this material in fender wells it will be necessary to employ the use of a 2-ton floor jack to remove the wheel and access the fender well. If the entire underbody were to be cleaned, a service lift would be recommended but is not necessary.

Second, gather the materials needed to remove the cosmoline. We have done dozens of vehicles over the years, and have found that using a body solvent in either an aerosol form or in a chemical resistant spray bottle works well. Also use a filtered mask and safety gloves to guard from fumes caused by the solvent cleaner.

Next, Spray the solvent onto the area and allow it to soak onto the surface. As the solvent works into the surface it will appear to dissolve. Agitate with assorted detailing brushes to accelerate the dissolving. Re spray the area to flush the material away from the vehicle. Solvents will continue to work as long as they are kept wet. Continue to re spray areas of difficulty until the cosmoline has been completely removed. Cosmoline can also be hand wiped with a shop towel on areas such as strut towers and smooth parts. Textured areas work better with the spray application process as this flushes the material away more completely.

After the area has been completely cleaned, spray a general purpose cleaner or water based degreaser onto the area and rinse with water to remove any solvent residue. Follow with compressed air to force dry the area and inspect for any hidden pockets of cosmoline. Repeat the following procedure until the desired affect is achieved. Reinstall skid plates, wheels and properly torque lug nuts and bolts to factory specifications.

The amount of time necessary will vary from vehicle to vehicle. Like any other detailing procedure, patience will be rewarded with good results.