Underbody cleaning

Underbody cleaning is the act of cleaning the underside of the car to remove any dirt and restore the looks as when the car was new. This is a tedious and labor intensive job, but good cleaning products and tools can help to make it easier.

Why do underbody cleaning

The underside of the car gets dirty, just like the rest. This dirt is rarely removed, so the dirt keeps building up. Dirt stays wet for longer then a clean surface. This means that the surface is in contact with dirt and moisture longer than it has to be. If there is any surface damage, and any bare metal is exposed, this can result in corrosion and oxidation. Just like washing a car is part of maintanance, cleaning the underbody is no different.
There are also people who do it because their car goes on shows, and needs to look mint at any time.

Tools that can help

Although it is still a labor intensive job, tools can help to make it easier on yourself. A few of these tools are:

• Pressure washer, to clean off dirt and grime more easily. If you have a pressure washer that can give clean water, it’ll be even better.
• Steam cleaner, to loosen up oil and dirty spots.
• Air compressor (or air blowing device) to blow out water from small spots and crevices that you can’t get into.
• A brush (both soft haired and hard haired), to agitate the cleaning solution and to get in small spots and crevices.
• Polisher, if you feel the need to polish certain surfaces (like polishing the exhaust)
• MF towels, do not use new ones. There is a chance that they get dirty or damaged irreversibly
• Glue and tar remover, there might be tar on the underside

Products that can help

Certain products can help to make the underbody cleaning job a little easier. These are aimed at cleaning.

• Snow foam, to loosen up dirt as much as possible.
• APC, to remove general dirt and grime.
• Engine bay cleaner, to remove very dirty and greasy spots.
• Fallout remover, to remove any iron oxide contamination.
• Traffic film remover, to clean as much of unwanted contamination as possible.
• (Metal) polish, to get some shine on those dull and oxidized parts
• Grade 000 steelwool, this can help to remove some contamination on very hard surfaces like metal

Things to look out for

There can be several things you need to keep in mind when cleaning the underbody, or that can help you to prepare better to the job at hand.

• You are probably going to work above your head, so keep in mind that are likely to get wet
• Since you are working above your head, there is a good chance that products will drip on you, protection is advised
• Protection for the eyes and mouth are highly recommended, protection for the skin can also be very important depending on what products you are working with
• Be careful around sensitive areas such as brake lines, electric wires etc.
• Take care with certain liquid, they are not always safe for wheels
• Use plenty of water to rinse of the cleaning solutions you are using
• Dry the area, dried up water can cause water spots and seeing as ou might get water in sensitive areas, it might pay off the dry it as best as possible
• Some car have an engine cover on the underside, removing this allows you to clean certain parts more thoroughly
• Polishing the ‘paint’ on the underside might not work, some cars have a type of coating on the underside that can’t be polished. Or you risk removing the protective coating
• It is difficult to protect the underside of the car. A wax will be difficult to buff off, the most used product is often a liquid spray-sealant.