Are 33 Inch Tires The Same As 285? The Complete Size Guide

Mounting the wrong size tires on your vehicle can have a significant impact on handling, braking, and the overall condition of your vehicle. It is important to choose the right size tires as it will improve your vehicle’s overall performance and increase the lifespan of your tires and vehicle.

Are 33 inch tires the same as 285? Yes, 33 inch tires are the same as 285, where 285 represents the width of the tread of the tire in millimeters, whereas the diameter of the whole tire is measured in inches, and that is 33 inches.

As it is, a bit technical many of us usually end up confusing ourselves. To make it clear and precise, 285 is the metric size code for 33-inch tires, specifically 285/75/16. 

By reading this article, you will gain a comprehensive understanding of why and how are 33 inch tires the same as 285. You will also learn how to properly fix them to ensure the comfort and safety of your vehicle

Tire Measurement Systems And Common Diameters And Widths

Different nations use varying systems to measure their tires, these are three main common diameters for tires: 33 inches, 35 inches, and 37 inches. Since vehicles differ in weight, volume, and size, each has different tire size requirements. 

Moreover, there are several standard measurements for tire width as well, including the most common ones 275/70R18, 275/60R20, 285/75R16, and 285/70R17.

For example, take 275/70R18; here, 275 is in millimeters which refers to the width of the tread. 70 is the aspect ratio which means the height of the tire.

Avoid mixing tires and wheels because a tire is the rubber portion, whereas a wheel is a metallic portion). 18 is the diameter of the rim of the tire.

While wider tires do offer better grip on the road, it’s important to use tires with recommended diameter and width to improve fuel efficiency, save money, and reduce your environmental impact.

Proper tire size is crucial for road safety and would go a long way in preventing any mishaps.

Calculating Tire Size Using Metric Measurements

Lets take a 275/60R20 tire example here –

275 is the width of the tire. It should be converted to inches and hence, divide it by 25.4

275/25.4 = 10.83”

70 is the aspect ratio which gives us information about the height of the tire.

10.83” x 0.60 = 6.5”

20” is the diameter of the rim.

2(6.5”) + 20” = 33”

Hence, the size of the tire is 33 inches.

Now that you have understood how are 33 inch tires the same as 285. You can use this same formula to calculate the size of other tires as well.

All the measurements of the tires in the table round off to a 33 inches tire.

Measurements of the tireTire width (mm)Tire heightDiameter of Rim
275/70R18275 mm7018″
275/60R20275 mm6020″
285/75R16285/75R16285 mm7516″
285/70R17285 mm7017″

Metric vs Millimeters

The metric tire size system measures the size of the tires. The measurements of the tire are in millimeters as well. Using millimeters helps in showing clear diameter size because it is a smaller unit and is easiest to use while measuring small lengths in detail.

Millimeters are easier to use for smaller measurements. The tires have their measurements written on them.

Understanding Tire Terminology

Here is the meaning of all the necessary technical terms from the tire terminology which the professionals use so that next time when you go to a mechanic shop, you can understand them better and more effectively.

What is a prefix?

It is a code in the form of alphabets that gives information about the tire, and the manufacturing company assigns alphabets. Each letter is assigned a unique meaning.

It gives us more insight into the vehicle and the tires of the vehicle, which is extremely necessary. These are the most common prefixes 

  • Passenger Car (P)
  • Temporary Spare (T)
  • Extra Load (XL)
  • Light Load (LL)
  • Standard Load (SL)
  • Heavy Load (HL)
  • Light Truck (LT)
  • Trailer (ST)
  • Commercial Vehicle (C)
  • Motorcycle (M)

What is section width?

The section width of a tire is the measurement of the tire’s widest point from one sidewall to another in millimeters. It starts from the inner sidewall and ends at the outer sidewall, excluding any additional features like the sidewall lettering.

What is the aspect ratio?

On the division of the tire sidewall (the rubber portion) with the tires width aspect ratio percentage is generated. The higher the aspect ratio, the smoother the ride, but a lower aspect ratio makes controlling the vehicles easier but may result in a stiffer ride.

What is speed rating?

The speed rating is the highest speed the tires can sustain for longer periods of time without heat built up from friction between it and the road. The higher the speed rating, the better the quality of the tire, and they work better at higher speeds as well as normal or slower speeds.

What is construction in tires?

There are three types of construction in tires-

1. Radial

2. Bias

3. Belted bias

The best one of all is the radial tire construction. They are more flexible and are made with well-bonded rubber layers, which are covered by crisscrossed rubber cords under the tread of the tire. They are secured and wrapped in the form of beads at the edges.

The sidewall and tread are two of the major parts of the tire. Sidewall is the outer length of the tire from its rim to the tread. The tread is the width of the tire that stays in contact with the road.

What Is Rolling Resistance  

Rolling resistance is a type of force that lowers the rolling resistance of tires by opposing motion and results in improved handling and better fuel efficiency.

What Is Load Index

The load index represents the maximum load that a vehicle can sustain at a given speed. The load index units are generally printed on the sidewall.

What Is Pitch Sequence

The pitch sequence is evaluated by the positioning of the tread blocks and grooves on the tire. If the spacing between the tread block and the grooves has been adequately positioned, then the tire noise drastically decreases and the comfort of the ride increases.

How To Fit A 33 Inch Tire On Your Vehicle

Time needed: 25 minutes

By following these easy steps you can fit a 33 inch tire on your vehicle

  1. Tire Size Consultation

    Consult a trusted tire mechanic to evaluate the maximum tire size that can be mounted on the vehicle.

  2. Choosing the Right Tire

    Select the tire that does not compromise the comfort and suspension of your vehicle. Ensure that the tire is compatible with your vehicle’s weight, size, and intended use.

  3. Measuring Wheel Well Clearance

    Measure the available clearance in your vehicle’s wheel well to make sure that there is enough space to mount the larger tire.

  4. Consider Lift or Leveling Kit

    If the clearance is less consider opting to install a lift kit or levelling kit as it will increase the clearance to the required amount.

  5. Vehicle Jack and Elevation

    Park the vehicle on a flat surface and fix the jack underneath it to raise it to a higher level.

  6. Loosening Lug Nuts

    Use a lug wrench to loosen the lug nuts in a counterclockwise direction. Apply pressure on the lug wrench from your foot, while keeping the lug wrench perpendicular to the ground to avoid any injuries.

  7. Installing the New Tire

    Install the new tire onto the wheel. Using the lug wrench tighten the lug nut properly.

  8. Checking Fitment and Clearance

    It is crucial to check for proper fitment and clearance of the tire. Make sure there is enough space in the wheel well to accommodate the larger tire size, and that it does not rub against any other parts of the vehicle.

  9. Test Drive and Tire Pressure Adjustment

    Test drive the vehicle to ensure that the larger tire does not cause any handling or stability issues. Adjust tire pressure as necessary to ensure optimal performance and safety.

What Is A Lift Kit

A lift kit, as the name suggests, is used in lifting the vehicle so it is raised a few inches more above the axles. 

Lift kits are a common choice for those who enjoy off-roading, as it improves the ground clearance of the vehicle and also make installing larger tires possible without rubbing against the fenders or other parts of the vehicle

What is Wheel Offset

Wheel Offset

The distance from the hub to the centre line of the wheel is known as the wheel offset. It is necessary for the offset to be proper for easy handling of the vehicle. There can be three kinds of offset-

1. Positive offset – They are usually found in the front wheels where the hub is closer to the outer visible portion of the wheel. It moves the wheel towards the vehicle.

2. Zero offset – When the centreline and the hub of the wheel coincide in one line.

3. Negative offset – Negative offset is where the mounting surface of the wheel is positioned away from the vehicle. In this setup, the hub is located on the rear side of the wheel.

Fender & Arch trimming to fit 33’s

The fender is the curved portion that sits over the wheel of the vehicle. They are made of rubber and help in preventing dirt and debris from flying over the body of the vehicle while driving.

To fit 33-inch tires, you might need to trim the arch a little. First off, make a small cut on the fender to cut out the pinch weld in that area and fold the modified part back in place. Secure the fender back on it.

Sizes Of Wheel Arches

To make room for wider tires, the arches of the vehicle’s wheels may need to be trimmed. It helps in preventing the suspension of the vehicle from rubbing on the tire. Hence, the size of the arches affects the size of the wheels as well.

In order to fit the fender on the arch, trimming the arch is necessary to make enough space for the wheels to avoid rubbing and damage.

Yes, 33 inch tires can fit on a stock vehicle with no lift. However, it’s important to use proper backspacing to pull the wheels away from the body and prevent rubbing. There may still be some rubbing, but it can be minimised with proper wheel and tire size. The recommended tire size for a stock vehicle is 255/80R17

Why You Need To Lift Your Vehicle For 33 Inch Tires

It is important to note that lifting your vehicle can also come with some risks and challenges. For instance, improper installation of lift kits can lead to issues such as poor ride quality, reduced stability, increased wear and tear on suspension components, and potentially dangerous handling characteristics.

Therefore, it is essential to have your vehicle lifted by an experienced and qualified engineer who can ensure that the lift kit is installed properly and that all necessary adjustments and modifications are made to ensure safe and reliable performance.

Benefits of lifting your vehicle for 33 inches of tire 

  • Increased ground clearance
  • Better wheel articulation
  • Better approach and departure angles
  • Enhanced aesthetics
  • Improved towing and hauling capacity
  • Enhanced visibility 
  • Reduced risk of bottoming out

What Size Is A 33 Inch Tire On A 20 Inch Rim

It is possible to fit and is ideal for 33 inch tires on a 20-inch rim. There can be different combinations on the basis of rim width and diameter. The diameter would be 851 mm, and the width would be 11.2”. Smaller wheels weigh less and can lead to saving up on fuel and expenses.

Conclusion – Are 33 inch tires the same as 285

Wider tires have a better grip on the road, but you must use tires of the recommended diameter and width. Always choose the right tires as it can lead to less usage of fuel, which would prove to be good for both financially and for the environment.

Before mounting a larger size tire on your vehicle it is important to understand the dimensions of the tire to safely mount them

Proper tire size is crucial for road safety and would go a long way in preventing any mishaps. The division of the tire height (the rubber portion) with the rim of the same tire gives a percentage which is the aspect ratio. 

It’s highly recommended to always have a spare tire in your vehicle to be prepared in case of a tire failure or blowout while driving. A spare tire provides a temporary solution until you can get your damaged tire repaired or replaced. One popular option for a spare tire is a donut tire, also known as a space-saving tire.

Now that you have understood how are 33 inch tires the same as 285. You might opt for 33 inch tires or any other larger size depending on your individual driving needs and preferences, but it’s always a good idea to consult with a trusted tire professional to help you make the right decision.

Are 33 inch tires the same as 285 – FAQS

Up to 3 inches of suspension lift and 1.25 inches of body lift would suffice for a Jeep Wrangler.

A two to three inch lift is necessary to fit 33” tires on a 3rd Gen Tacoma.

The tread width of a 285 55R20 would be 11.2”, and the diameter of the rim would be 20 inches. The height of the sidewall would be 6.2”. The hole diameter would be about 32.4”.

Absolutely. You can fit a 285 tire on a 9.5-inch rim. They would fit perfectly, but avoid going any wider.

The tire rim width would be about 10.5” for a 285 mm tire.

Absolutely. You can put 285 tires on 275 rims easily, as the rims of both tires are similar in size.