How Is Ground Clearance Measured?
Do you know how vehicle manufacturers determine how they measure “Ground Clearance” and why it matters?
We’ll discuss ground clearance and other factors that might affect your vehicle choice and use.
How Is Ground Clearance Measured?
Ground clearance is measured by car manufacturers by measuring the distance between the ground and the lowest part of the vehicle not including the tires, mudflaps, or other flexible parts of the vehicle. Manufacturers use multiple references to different kinds of height, and we’ll go into those too.
Let’s learn more about how ground clearance is determined, what the other ride measurements mean, and why ground clearance is an important measurement for off-road and other types of driving.
We are going to dig in and learn about angle measurements and what else you can use to ensure you are off-roading safely.
Why does ground clearance matter?
The average driver who is looking to drive their vehicle on the highway and regular side streets has probably never thought about ground clearance.
People who want to know the ground clearance for a vehicle are likely planning to go off-road, where they might not necessarily be driving on streets or roads.
A person who takes their SUV or truck off-road might care more about the ground clearance because ground clearance measures the distance between the ground and sensitive parts of the vehicle.
This is especially important when using a vehicle to crawl over rocks, mud, or anything that could impair the vehicle’s ability to move.
We find safety to be pretty important for off-roading.
What is the ground clearance measurement based on?
The answer greatly depends.
A vehicle’s ground clearance can start with any part of the car, often including
- Exhaust system
- Bumper
- Plastic shielding
- Chassis brace
- Housing for differential
Any of these parts taking a direct impact from a rock can create some serious damage and may limit the vehicle’s ability to move, and could require a visit to the service center, body shop – or just your garage.
How do I know my vehicle’s ground clearance?
There are a couple of ways of knowing your ground clearance for your vehicle.
Your Vehicle’s Manual
Vehicle manufacturers who produce trucks and off-road SUVs tend to include the vehicle’s ground clearance in the manual, so you can often reference their own engineer’s numbers to check just what you can do with your car.
Measure it yourself
If you modified something on your vehicle, including the exhaust system, bumper, or anything else, you should measure the actual distance yourself from the bottom-most part of the modified part to the ground.
We suggest a flexible tape measure for the purpose if you are able to physically fit under your vehicle.
Using a roller board might be easier for some people to get underneath.
This is especially necessary after modifications because you can’t be guaranteed how much ground clearance you’ll really have.
How much ground clearance does my vehicle need?
An easy answer to that is: it depends.
There are a few categories of driving that might need different levels of ground clearance:
Gravel Tracks
Gravel tracks often require a ground clearance of 6.6 to 8.7 inches.
Gravel spray can often throw small, hard rocks into your vehicle’s undercarriage and cause problems.
Getting high enough above gravel also helps with traction.
Overlanding
Overlanding is often defined as more serious off-roading where you might be crawling over rocks and are generally exploring – without roads.
The needed ground clearance is slightly higher than gravel at 8.8 inches to often around 9.4.
Serious Rock Crawling
Get at least 10 inches of clearance if you intend to drive over large rocks.
Rocks can be unpredictable (unless you intend to measure them?) and can cause some damage to your vehicle.
More important than ground clearance: Angles
There are a couple of important factors here, but we’ll get directly into potential problems: If you don’t have enough ground clearance, you risk getting stuck in a spot where a piece of your vehicle prohibits you from moving because it’s caught on something underneath.
You also risk damaging the vehicle itself and potentially being unable to drive properly.
Problems can come from a couple of areas:
Approach Angle
The approach angle is how much space and height you have in the front of your vehicle.
If you found yourself going rather uphill, or a taller object, you’ll want to know your vehicle’s approach angle too as an assurance that you can drive over without damage.
To put this in a more everyday context: Some people have lowered bumpers and steep driveway entrances.
If the driver turns too fast into the driveway, they risk banging the bumper on the driveway repeatedly, making a lot of noise, and scuffing that bumper.
An off-road driver trying to drive over a tree stump, rock, or other big object risks getting stuck on the object or scraping their front bumper or even axle.
Departure Angle
The departure angle is much like the approach angle, only backward.
The departure angle is the steepest angle a vehicle can take without banging the exhaust or rear bumper against something.
The highest risk here is more often just the bumper versus other potential important engine parts with the approach angle.
Break Over Angle
This is the lowest part of the middle of the vehicle.
If the lowest part of your vehicle is in the middle, you have the highest risk while driving directly over something.
Having a part of the terrain gets into the middle of your vehicle can be bad news, especially if it manages to prevent you from getting wheels on the ground.
The Importance of knowing
Since many vehicles have different angles – and off-roaders often find themselves up or downhill to pass terrain, the angles can be more important than actual ground clearance.
The angles are also a bit more predictable and can sometimes literally be measured with in-car tools and out-of-car tools.
Tires, Lifts, and More: What else is important for creating ground clearance?
There are ways of creating more ground clearance, and these changes are often necessary for more serious off-roading anyway.
Tires
Tires are available in a variety of sizes depending on your vehicle – and most vehicles like Jeep that go off-road on a regular basis have the ability to readily accept a larger tire.
Imagine you need 8” of ground clearance, but your vehicle only offers 6.5” to 7”.
Adding tires that are an inch or two larger than what you had on before – like for example 16” tires, you can add an inch or two of ground clearance.
Tires can help in more than one way when trying to improve off-road experiences, with more aggressive treads available.
You’ll want a true off-road tire if you plan to go off-road on a regular basis, and something more extreme if you want to rock climb.
Are tires cheap? Not necessarily, but they often provide significant help with getting around anyway, and can always be resold – as they are fairly easy to uninstall.
Coil Spring Spacers
These are spacers that sit between your coils in the suspension system.
Coil spring spacers don’t provide a significant gap, usually a half-inch or less- but that can make a big difference in getting over objects.
Lift Kits
Lift kits raise the vehicle’s suspension and create more clearance underneath the vehicle, in addition to allowing for larger tires to be used.
Lift kits are popular for off-roading to allow a driver to use a vehicle that might not normally have the ground clearance necessary for the off-road experience they want.
We do have to note that lift kits have the potential to impact your warranty as well as resale value of your vehicle, as well as other parts of your vehicle – potentially positively or negatively.
Cameras and tools for ground clearance
There are tools out there that can help you better know when you are in danger of striking an object or at least getting a good view of what’s underneath.
Cameras
Some newer off-road vehicles like the Hummer EV, amongst others, have cameras installed underneath the vehicle, protected by your skid plates, that offer a glimpse of what’s under your vehicle.
They can also measure when you are too close – especially if you can’t just measure objects.
Cameras give you the opportunity to turn the vehicle or just back up when you feel like you are going to have a problem coming up.
A spotter
So this isn’t a tool – but a friend coming along with their vehicle can help you know when you should or shouldn’t go – and potentially help drag you out of the mud or a precarious situation.
Which vehicles are best for ground clearance?
Generally speaking, trucks and large SUVs provide good ground clearance.
Jeep brand SUVs are known for taking serious consideration for ground clearance, as the newer Jeep Gladiator provides one of the highest standard clearances for a consumer vehicle at 11.1”.
The Ford Ranger is also a good example, at 8.9” without modification.
Most trucks have ground clearance, but the average truck doesn’t quite have the ground clearance for serious off-roading.
Many manufacturers like Ford, Chevrolet, Toyota, and numerous others build a standard pickup truck that emphasizes comfort and towing in addition to a truck that is built higher and wider to get over serious obstacles.
Is there a difference between ride height and ground clearance?
The ride height is technically the distance between the lowest part of your tire and the lowest part of your vehicle.
One of the biggest technical differences here is that in the case of some vehicles, ride height is actually adjustable
Like a lift kit, some vehicles have suspension adjustments built-in.
These can be both for the purpose of going off-road, and some drivers just like the idea of sitting higher in their vehicle whether for practical or visual purposes.
The two really aren’t interchangeable because ground clearance is less often an adjustable number without modifying the vehicle or tire.
More measurements to consider
In addition to ride height, ground clearance, and others, we have a few more measurements that might help – at least to know about.
Axle clearance
This is partially encompassed with the front angle, but it also has a specific height. This is the vertical measurement of how far off the ground the axles are.
This is important because a stuck axle means you aren’t moving.
Running clearance
Here is where things can get a little confusing: Some manufacturers who aren’t all about off-roading might give you the running clearance of a vehicle instead of the ground clearance. Running clearance refers to any parts of the vehicle involving the suspension – or unsprung clearance. In other words, the running clearance can include body components that are important to off-roading.
These are sometimes used interchangeably, and erroneously as the ground clearance is important. Off-roaders don’t want critical parts scraping against rocks or getting drowned in mud.
Suspension clearance
As you might suspect, this is the distance between parts of the suspension and the ground. This is a specific measurement and is usually higher than the ground clearance.
Does higher ground clearance make a vehicle unstable?
Ever seen a vehicle in a parking lot and believed it doesn’t provide a very comfortable ride, or is loud? You might be right. A higher ground clearance can generally make a vehicle higher up, and less stable.
To counter this, the vehicles often come with wider tires and different suspensions that spread weight out more evenly.
Should you corner at high speed with a vehicle at higher ground clearance? Might not be comfortable. Otherwise, traveling 70mph on the highway might feel difference from coasting in a sedan, but it isn’t more dangerous for normal driving.
While others who are unfamiliar with high ground clearance vehicles might warn you they are phone to flipping – you can instead invite them to go off-roading with you to demonstrate how they really work.