1 Except on vehicles with a wax-based underbody protective coating, have the whole of the underframe of the vehicle steamcleaned, engine compartment included, so that a thorough inspection can be carried out to see what minor repairs and renovations are necessary.

2 Steam-cleaning is available at many garages and is necessary for the removal of the accumulation of oily grime which sometimes is allowed to become thick in certain areas. If steam-cleaning facilities are not available, there are some excellent grease solvents available which can be brushapplied; the dirt can then be simply hosed off.

3 After cleaning, position the vehicle over a pit, or raise it at front and rear on ramps or axle stands (see “Jacking and vehicle support”).

4 Using a strong light, work around the underside of the vehicle, inspecting it for corrosion or damage. If either is found, refer to Chapter 12 for details of repair.