Think your car is fine after driving through a flood? You need to know this…

Thousands of cars have been submerged or terminally damaged in the recent floods. That aside, far more would have had to negotiate rising waters or large puddles in the hopes of driving to safety or getting to where they needed to be.

Even if your car suffered no (immediate) damage when it passed through water, it is wise to get the following items checked and/or replaced as necessary.

How do I know if I have driven through high water levels?

Every vehicle has a water wading depth depending on the type of vehicle and application.

Also read: How driving through floods can damage your car, and here's how to do it safely

Pick-up trucks are designed with this in mind and thus will have the highest water wading depths, which typically range between 0.6- to 1.0-meter from the road level.

However, SUVs and sedans have much lower water wading depths. Therefore, even if you have driven through water that was half the height of your tyres – you might have already exceeded its recommended threshold.

To be on the safe side, you should not drive in water that’s any higher than the lower edge of your car's bumper.

The main reason for this is many cars have their air intake nozzle positioned at the bottom of the bumper, which can suck water into the engine - and trust us, a 'hydrolocked' engine is something you really do not want.

Thus, even if you have driven through a relatively large puddle or standing water, it is wise to check the following as soon as you can.

Also read: So your car was stuck in a flood, now what do you do?

Get the vehicle on a lift and check the undercarriage

After driving through a flood, it is wise to get your car hoisted to check the entire undercarriage for signs of dirt, debris or damage.

In certain cases, debris or mud can get stuck or snagged on chassis and suspension components, in other cases, underbody protection panels may have come loose after coming into contact with water.

This will be a good time to inspect your car’s fuel lines, differential, and exhaust system too.

Inspect your tyres and brakes

At the same time, roll the tires and inspect for signs of damage or puncture, floods typically wash away debris such as building materials and nails (typically from roadworks) which can damage your tyres.

Get a good look at your brakes and crucially your brake lines, they too can pick up debris and get damaged as well. A further measure is to refresh and bleed your braking system to ensure your brake fluid is nice and clean too.

Drain and replace your engine oil

It is highly recommended that you inspect and replace your engine oil if you have driven through high waters. Cars that have been left for hours in tyre-level height also need to be have its lubricants checked for water contamination.

Flood water usually carries sand and mud which can make its way into your engine through the oil sump gasket or other sealing points and wreak havoc in your engine.

To play it safe, a relatively cheap oil change will ensure that you drain and remove any debris from the engine.

Refresh your transmission oil

The transmission is typically positioned at the lowest point of the vehicle and thus its is most exposed to moisture or debris when driving through a flood.

Depending on the type of transmission, some may have cooling fins or breather outlets positioned on the top side of the transmission casing which can draw in water.

That aside, there are also numerous sensor bungs and sealing gaskets that can present cavities for water to enter the transmission. The older your car is, the more prevalent this issue is.

Thus, it is wise to drain and refresh your transmission oil to ensure you have good clean oil protecting one of the most expensive components in your car.

For 4x4 vehicles, make sure you check the rear-axle's differential for sign of water contamination, because it too has a breather valve that water may enter.

Clean your air intake system

You do not want to risk having any moisture entering your engine (even days later), therefore it's best to inspect and if necessary, remove and clean your air intake system.

It is most important to remove the air cleaner box/compartment and thoroughly dry out any moisture trapped inside. This might be a good time to replace the air filter element too.

Get a comprehensive diagnosis done

It is highly recommended to get an On-Board Diagnostics (OBD) scan to comprehensively check the car’s computers and electronic subset systems.

It is not uncommon for sensors and electronic connectors to prompt error codes or malfunction when they come in contact with water or debris.

An OBD scan will ensure every one of them is working as they should and point out any issues that could be potentially expensive to fix later on.

Also read: A simple way to check if a used car has had flood insurance claims

Also read: No flood insurance? Repairs too expensive? Try selling your old car to Pickles!