Underbody Coating

Under-body coating, its types and its pros and cons:

Underbody rust-preventive coating

The underbody coating that is most commonly used on cars in India and supplied by companies such as 3M is a thick, rubberized paint that forms a 2-3 mm thick coating all along the underside of the car when sprayed on. You also get a thinner clear coat underbody coating which is like a lacquer that coats the entire underside of the car. Some even inject rust-preventive coating material into crevices such as the bottom of doors and door sills, to protect them from rust.

Some car manufacturers already offer some underbody coating straight out of the factory which is usually sprayed inside the wheel arches and under the floor board of the car.

Here are some benefits of underbody coating

Rust Prevention
Ideally any additional underbody coating should be applied when the car is brand new and clean. Car manufacturers use thick paints and sealants for the underbody, but adding an underbody coat especially in coastal cities is useful. Salt water tends to corrode cars really badly.

On bad roads, flying stones and pebbles can chip off the original underbody coating and leave the metal exposed. Using an aftermarket underbody coating offer extra protection.

Sound insulation

The thicker underbody coatings used on cars also act as effective sound dampeners. They can reduce road noise and tyre noise and make the cabin seem quieter – due to the sound absorptive nature of rubberized paints.

Easy maintenance

A uniform black underbody coating gives a car a clean look. It also makes the car easier to maintain by just hosing the underside down. You can be confident that slush build up won’t lead to rusting easily. Most underbody coats these days come with a five-year warranty, which is the lifetime of such a coating.

Here are some of the downsides to underbody coating:

High cost

Cost of underbody coating has come down, but is still expensive. This is because underbody coating offered by a car dealer is one way in which they make money off the customer.

Risk of damage during application 

Care must be taken while applying underbody coating. This thick rubberized paint if not applied properly, can get into moving mechanical parts and cause premature failure – such as into the U-joint or CV joints in a cars propeller shaft or drive shafts. They can also hinder smooth movement of suspension components, if applied incorrectly. And there’s also the risk of overspray on to the car’s paint finish on the lower edges of the car.

Teflon coating

Teflon coating is the generic name given for a clear-coat paint sealant that’s applied to the painted surfaces of the car. It is a brand originally owned by Dupont, but now has become generic to the category of PTFE paint sealants. This protects the car’s painted finish and offers a brilliant shine, keeping the vehicle like new for a long time.

Here are the benefits of Teflon coating:

Minor scratch protection

Teflon is a thick clear coat surface that is very slippery. It protects the cars surface from swirl marks and scratches caused by dust and cleaning with a dirty cloth.

Enhances gloss

Putting a clear coat hard wax or Teflon coating on a car evens out the unevenness in the painted surface by filling up minor pits and cracks. This enhances the reflective capability of the paint, giving the car a high-gloss finish that looks like a mirror.

Here are the downsides of Teflon coating:

Not long-lasting

Teflon coating does not last long enough. The effect can wear off in about six month’s time after which it will need to be redone or you have to switch to a hard-wax polish for the car. The benefits of a hard-wax too are not long-lasting, but can be re-done at a much lower cost.

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