Why Does The Back Of My SUV Get So Dirty?
Why does the back of my SUV get so dirty? It’s all about the shape! You spend an entire Saturday afternoon washing and waxing your SUV. Your vehicle shines and sparkles as the paint gleams in the sunlight. Take it on one drive, and the back of your SUV is covered in dirt. All of that work for nothing. Today I’ll share why our SUVs get so dirty, and how to keep them cleaner.
Contents
- Why does the back of my SUV get so dirty?
- Air movement around SUVs
- SUV shape encourage dirt
- How to keep the back of your SUV clean
Why Does The Back Of My SUV Get So Dirty?
The tires kick up mud, dirt, muck, and grime as you drive. It all gets caught up in the air flowing under the vehicle. The dirty air exits out the back of the vehicle and gets sucked into the low air pressure void behind your SUV. The trapped circulating air picks up more grime as you drive, becoming dirtier. This dirt, dust, and sand get deposited onto the back of your SUV.
To make matters more complicated, the flat back shape of the SUV doesn’t get exposed to water like the back of a car does. This makes it harder for the SUV to get naturally rinsed like a car’s rear window and trunk do. As a result, the dirt and grime continue to build until the back of the vehicle looks significantly dirtier than the rest of the vehicle.
The back of SUVs get dirty for a few reasons, but we can boil them down to:
- Air movement
- Shape
- Wind vortex
Air Movement
When a vehicle moves through the air, it creates air turbulence. This happens with all motor vehicles and airplanes. The vehicle moving through the air breaks the air in front of it and pushes it out of the way. This creates turbulence and wind, so the air moves around the vehicle.
Automotive manufacturers use wind tunnels to simulate this airflow. Their goal is to create a more aerodynamic vehicle. Aerodynamics directly impacts the vehicle’s performance, handling, and fuel economy.
SUV Shape
Your SUV has a wedge-like body shape, with the front of the vehicle being smaller than the back. The engine bay portion of the vehicle is the smallest part of the wedge. The back of the SUV is the largest part of the wedge. This means the back of your SUV is essentially flat with a straight vertical plane.
The front of the SUV cuts through the air well. This is because the vehicle manufacturer focused on the front of the vehicle for aerodynamics. The air flows nicely up and over the hood and the top of the vehicle. The same applies to the sides of the vehicle.
Wind Vortex
The flat shape SUVs have on the back creates a space where air doesn’t naturally flow. This leaves a void that sucks the air up from flowing underneath the vehicle. The air gets sucked up, trapped, and pushed back down by the air flowing over the top of the vehicle. The circulating air creates a vortex where the air cycles around. The faster you drive, the faster the air flows. The faster-moving air creates a more intense vortex.
Cars have a more uniform shape on the front and back sides. The low trunk allows the air to flow up, over, and back down again. This keeps the air flowing smoothly over the entire vehicle and away from the car, and it also allows water to flow over the entire body of the vehicle. The result is less of a wind vortex created and a cleaner car.
How To Keep The Back Of Your SUV Clean
The obvious answer is to wash your SUV more often. But this is time-consuming and doesn’t address the issue. So instead, you need tips for preventing the vehicle from getting dirty.
Cleaning and Detailing Products
Use the proper cleaning and detailing products. After you wash and dry your SUV, use a sealant or polishing product that creates a slick surface. Look for a product that repels dirt. This will make it harder for the dirt to stick to your SUV. Use a different product for your paint and the glass. These are different materials, and they need different products for the best results.
Mud Flaps
Adding mud flaps to your vehicle helps to prevent the dirt and mud from getting kicked up. This helps to keep the air flowing around your vehicle cleaner. For a good example, look at semi trucks driving on the highway. These large trucks have a similar flat back and suffer from the same dirty rear-end issue. As a result, semi-trucks and trailers with mud flaps look cleaner than those without them. The same benefit happens for SUVs.
Durable rubber flaps attach to the lower side of the vehicle just behind the tires. You can place them just behind the rear tires. Front tire guards also help keep the side of your vehicle cleaner.
Spoilers
Some automotive manufacturers have heard the complaint of owners. New SUV models come with spoilers that sort of look like fins that are attached to the back of the vehicle. You commonly see them at the top of the SUV back. Sometimes they are solid, and sometimes they have holes in them.
A spoiler’s purpose is to change how air flows around the vehicle without having to make significant changes to the structural design or shape of the vehicle. You can easily add an aftermarket spoiler to your current SUV.
The spoiler may help direct the air flowing over the vehicle to flow downward, breaking the low-pressure void that pulls air up from the bottom. This keeps the dirty air from flowing upward. Other spoilers may direct the air flowing upward to turn and flow away from the vehicle with the air coming over the top. This stops the vortex effect that would cause dirty air to circle and redeposit dirt onto your SUV.
Drive an SUV and Deal With the Dirt
If you drive an SUV, you know the comfort, space, and convenience they bring. But dealing with a dirty backside can be tedious and time-consuming. Start by cleaning and detailing your SUV, and then consider adding mud flaps or spoilers.
