Wheel Offset: How to Get Started

You’re looking at pictures of sick rims trying to put together your wish list now that you’re ready to upgrade the wheels on your speed wagon. You see some wheels that look familiar but start noticing that some cars have wheels that seem to stick out from the car with huge amounts of space inside of them. Others have the spokes right at the edge and are almost tucked into the body for a clean look. 

So what’s going on here? These different styles are all the product of different amounts of wheel offsets.

At Rent A Wheel, we have professionals ready to go to help you find just the right fit for your car, but if you’re interested in doing your own research, here’s wheel offset explained to help you along. 

What is Wheel Offset?

Wheel offset is the measurement value of the different placements your wheel connects with the car and is always measured in millimeters. The wheel lug holes position might be closer to the street side, giving the tire that tucked-in look. Or it might be further from the street side for a sick deep dish appearance. 

These are positive and negative offsets. You can typically find the offset amount stamped onto your rim, either at the mounting surface area, on one spoke, or somewhere on the back. You should see something that says “ET: +40,” which means that those wheels are offset from the center 40 millimeters towards the front. The ET stands for the German word Einpresstiefe, which means “insertion depth.”

Different Types of Offset

If you were to slice a wheel standing up from top to bottom, that center is what we measure from where the wheel lug hole connection point is or how offset the connection point is from the direct center of the wheel. Get it? 

• Negative Offset is when the mounting connection surface is closer to the wheel’s back, further from the street side. This is what’s giving that deep-dish look. It’s connecting the car closer to the inside edge of the wheel, so there’s more room in the front.
  
  
• Positive Offset is when the mounting surface reaches past the centerline towards the front of the wheel, or street side, sometimes even becoming flush with the front of the wheel and tire. 
• Zero Offset is exactly what it sounds like- the center of the wheel is right where the connection surface is.

Negative Offset

As we mentioned, negative offset is when the connection point on the wheel is closer to the inside of the wheel from center. This gives the wheel a big feeling. You might see it on bright green Cadillacs cruising around. Like these wicked Scorpion SC-10s that have that huge amount of space with a classic chrome covering. If you love this look, let’s explore what this style is bringing to your driving experience. 

Advantages of Negative Offset

So besides looking seriously dope, a decent amount of Negative Offset comes its bonuses. For one, it increases the track of the car, which is the measurement between the centerline of two wheels on the same axle. 

By pushing the contact surface closer in, you’re pushing out the rest of the wheel. So the tire’s centerline is being pushed past where it might normally be, increasing the track. This can boost the amount of grip your car has while taking turns at high speeds, getting a wider surface area underneath the car to expand its center momentum control. However, this one is a bit of a double-edged sword--you’re getting better handling but losing some of the steering wheel feedback you might be used to. 

This means you can take turns a little stronger than a zero offset pair of wheels, but when you do start slipping, you’re less likely to notice with your hands.

Another benefit is for all off-roaders out there--more negative offset means your tires are pushed out, which leads to more grip as you’re trying to climb mountains and whip through muddy hills! Or whatever else it is you do, you mysterious adventurers. 

Disadvantages of Negative Offset.

Unfortunately, looking that sweet also comes with a price. Pushing the tires out that much puts extra stress on your axle, suspension, and bearings. Think of it as holding something up and reaching your arms out. You’re gonna wear yourself out sooner than if you were holding it in close. 

The other (maybe) obvious issue? If your wheels are poking out further, and the body of your sweet ride doesn’t, you know, have monster truck proportions, you’re more than likely going to start rubbing on your fenders if you turn more than a bit. This can be resolved mostly with extending your wheel well and fenders, but now we’re talking about more money than just a set of wheels. 

Overall it’s a specific look and style, and if you really want to push it, you’re most likely going to pay for it.

Positive Offset

Enough about negative offset. What about positive offset? This is when the mountain position on the wheel is closer to the street side of the wheel or the front of it. This leads to a more tucked-in, clean look. For a visual example, the Azara Are 505s, which, as you can see, have a smooth front look and a killer smooth, metal finish for just $61 a month.

Advantages of Positive Offset

Starting off with a bonus for the off-roaders with us, if your vehicle has big amounts of wheel well room, then a positive offset means you can fit more wheels underneath your vehicle without them sticking out. This makes squeezing through tight trails more manageable while still increasing traction through the dirt and mud. 

Another advantage is that you really don’t have to worry about rubbing your fender guards with positive offset wheels. Because they don’t stick out like negative offset wheels, you’ll have no trouble turning and worrying about your car’s body.

To counter the negative offset’s lack of steering wheel response, positive offset wheels will give you a much better idea of if and when you start to lose control so you can act quickly. 

Disadvantages of Positive Offset

Most of the disadvantages with positive offset wheels have to do with clearance- because you’ve moved the connection surface of the wheel to the front, now the tire and the entire wheel are much closer to the mechanisms of your car. 

For instance, if the spokes begin to get too close to your brake calipers, you’re limiting the amount of movement they can have. This can cause some damage to the brakes and rims, neither of which would be an easy fix. It’s important to leave a reasonable amount of room between the brakes and the spokes because both may warp and expand while driving under certain intensities. 

You might also be getting too close to your suspension system if you positively offset your wheels too far. Make sure to allow for plenty of clearance, and keep in mind bumps and turns when contemplating just how close your wheel can get to these parts. 

Why Change Your Wheel Offset?

As you might be noticing, there’s a lot of information and measurements that need to be taken seriously if and when you decide to go with a different wheel offset measurement than your current tires. You could seriously damage any number of things if you’re off, including your brakes, fenders, suspension, and axle. A good word of advice is to try not to add more than 5-10 millimeters of offset at a time, particularly if you’re working by yourself. 

But if you know what you need and what you’re looking for, don’t be scared away. This is your car, and if you want to change up to a custom wheel offset, you know what to do. Want those deep dish rims? Or getting a tighter wheel placement to get those squeaky clean lines? Maybe just bigger tires for your monster truck. Whatever it may be, just go in knowing that you have the information to figure out exactly which offset car wheels or offset truck wheels it is you need to buy. 

And if you still feel a bit uneasy, just talk with one of our professional fitters at RentAWheel.com, and we’ll help you find the perfect fit for what you’re looking for. We’ll even install it for free at one of our many Rent A Wheel locations if you buy with us. And with our flexible monthly payment plan, not only are we making things as easy as possible, but we’re also making them as affordable as possible. 

Sources:

Understanding Wheel Offset | Low-Offset.com

WHAT IS WHEEL OFFSET AND WHY IS IT IMPORTANT? | BimmerTips.com

An installer’s guide to wheel offset | ModernTireDealer.com