How to get the best wash for the undercarriage of your trucks

February 22 2021
Truck wash

When it comes to washing trucks, a fleet operator’s number one requirement is a high quality clean. Trucks are on the road and in action for long stretches of time - meaning a serious amount of dirt and grime can build up between washes. Constantly dirty vehicles can begin to reflect poorly on a business - especially when their trucks are a common presence in a local community.

But, if left to build up over time, dirt can also cause a truck lasting damage - with rusting a common outcome. This is why firms will want to ensure that when they do get the opportunity to wash their fleet, they do a complete job. But despite this, businesses frequently neglect one of the most important areas of the vehicle - the undercarriage.

But why is it so dangerous to leave a truck’s undercarriage dirty, what damage can be caused as a result and why is an automatic truck wash system the key to ensuring your fleet gets a thorough under chassis wash every time?

Why is it so important to clean a truck’s undercarriage well?

Hidden away and difficult to reach, a truck’s undercarriage can easily become chronically dirty. This will soon begin to affect the vehicle’s performance with irreversible damage even possible. This is what could happen to your trucks if you don’t protect beneath the chassis.

Chassis corrosion

One of the biggest dangers to the undercarriage of a truck may come as a surprise to you - salt. Your fleet comes into contact with salt more frequently than you might imagine - mainly during the winter months when roads are gritted around the clock.

While this certainly makes for safer driving conditions, it can also accelerate the oxidation of the metal components underneath a truck. This leads to corrosion of the exposed metal parts, making them more susceptible to other forms of damage during their day-to-day use.

Chassis rust

Prolonged exposure to water or moisture will ultimately lead to rust for untreated metals like iron that are found on the underside of trucks. Under a truck’s chassis - which is constantly being exposed to wet road surfaces, puddles and often mud - water often struggles to disperse naturally.

Mud can be the real killer for a truck’s undercarriage. When it cakes the metal components for prolonged periods, it lengthens their exposure to moisture and means rusting can occur quicker. When the undercarriage isn’t cleaned thoroughly, this mud can stick around for months on end, causing serious damage.


The smooth running of any vehicle - but especially a heavy-duty one like a truck - needs engine heat to be released to ensure a consistent temperature. Trucks are designed to dissipate heat largely from beneath, meaning build-ups of dirt here can be problematic. The more dirt, the less heat can be released and the hotter the chassis becomes. This eventually shortens the life of components and affects the running of the vehicle.

Under chassis truck wash solutions

So what’s the solution, and how can you ensure your fleet doesn’t suffer any of these fates? If your trucks are currently washed manually, it will be difficult to maintain regular under chassis cleaning of the appropriate standard. There are a few reasons for this:

  • Time. Lifting a truck and giving its undercarriage the attention it needs is a specialised job - and a time-consuming one. When you have a whole fleet to clean, there simply may not be enough hours in the day for full under chassis washes.

  • Chemicals needed. Extending the time and complexity further are the range of chemicals required to properly treat a truck’s undercarriage. Degreaser, rubber spray to protect from rust and even special undercarriage spray to repel dirt will all help.

  • The eye test. When time is limited, it’s natural to devote most of it to the most visibly dirty areas of a truck. The problem is that it’s difficult to get a good view of how clean or otherwise a vehicle is under the chassis. And as we found out before, dirt doesn’t even have to be that visible to cause damage.

So while the use of a manual pressure washer and a few specialist chemicals can give a truck’s undercarriage a thorough wash, this is unlikely to be a viable long-term solution for most operators. When it comes to washing an entire fleet, an automatic truck wash system is by far the best option.

Modern gantry or rollover wash systems are commonly installed with under chassis wash technology - something especially vital for truck fleets for the reasons we’ve outlined. Oscillating nozzles are used to deliver a more comprehensive clean with better coverage. This feature gives unrivalled undercarriage cleaning from a wash quality, time-saving, cost and efficiency perspective. These systems can easily be installed into an existing wash bay to give high-pressure cleaning from below. Sophisticated water distribution and oscillating brushes provide targeted washing in the areas dirt builds up while protecting sensitive components.

These under chassis features fit seamlessly alongside all the other benefits of truck wash systems, meaning it takes only a matter of minutes to deliver a full-vehicle wash far superior to what could be achieved manually. A highly economical use of water, power and chemicals - as well as significant labour and time savings - also make automatic wash systems far more cost and resource-effective.

At Wilcomatic, we’ve delivered the best in innovative truck wash systems for over 50 years. Our exclusive UK partnership with Otto Christ means we have an unparalleled range of cutting-edge technologies at our disposal to build the right solution to fit your fleet. Meanwhile, our high standard of customer service guarantees deliveries of your crucial wash consumables whenever you need them, plus expert support seven days a week.

Learn more about how a Wilcomatic wash system could benefit your truck fleet by contacting us today!

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