The letters and alphabets written on the wheel may confuse most car owners. For example, what does 7 J mean on a wheel? Let’s find out the answers to all such queries in the article below.
Your car’s wheels work hard every time you move on the road because it is the only component that comes in contact with the road surface.
Tires can get worn out with age and need replacement. But selecting an appropriate tire is quite essential for car owners. If you fail to do it, the tire will have premature wear and tear, and you might have to spend more money repairing and replacing them frequently.
While installing new tires for your car, you may observe various letters and numbers written in coded information inside the wheel. The letters and numbers are essential for you to understand because they will help you select the right wheel for your car.
In this article, we will try to answer questions such as what does 7 J means on a wheel, and similarly, other letters and numbers commonly found on the wheels.
What Does 7 J Mean On A Wheel?
The number 7 is the size of the inner width of the wheel in inches, and the alphabet J indicates the wheel shape when the tire bead sits on the wheels.
You need to remember that letter J should match with the markings of the tire. J is the most common letter used by most passenger cars, so even if you don’t check for it, you will most likely get it right.
Now that we have that settled let’s discuss more markings on the wheel and what they mean when you are buying a new one.
How To Read The Markings Of The Wheel?
You will find a series of markings, numbers, and alphabets written inside the wheel. Each marking written on the wheel has a meaning. You need to understand the code language to select the right wheel for your car.
Let’s take an example written inside the wheel as 7J x 16H2 5/120 ET47. I will explain here each of the numbers or alphabet written on the wheel marking. It may help you in picking the right wheel for your vehicle.
#1. Number 7
Here, the first number, i.e., 7, indicates the wheel’s rim width or the width in inches.
We know that an inch is equal to 25.4 mm. So in our case, the width of the wheel is 177.8mm.
#2. Alphabet J
Now the following letter after the letter 7 is the alphabet J which corresponds to bead profile. This letter is quite common in almost all passenger cars.
However, you will find other letters in some of the wheels like alphabet A, B, D, and others. Another thing you need to remember is that some alphabets can come under more than one profile— if that’s the case, you need to select the wheels accordingly for your vehicle.
Let’s look at the table below in which there are markings along with applications. It will help you know the meaning of the alphabet written after the first number inside the wheel.
|A||Bikes, motorcycles, trucks|
|B||Passenger cars but the wheel width should be 6 inches.|
|D||Bikes, motorcycles, lightweight and heavy trucks.|
|E||Lightweight and heavy trucks.|
|P,K||Old cars such as Bentlys|
|S,T ,V,W||Utility vehicles|
#3. The LowerCase Letter x
Let us now move to the lower-case letter x, which indicates the wheels are constructed in one piece.
#4. The Number 16
Next, we have the number 16, which means the diameter of the wheel. So, in our case, the diameter of the wheel is 16 inches or 406.4mm.
If you select the wheel with 16 inches diameter, the number 16 should be written on the sidewall of the tire you choose. You cannot compromise on this number—selection of the wrong number can cause your tires to be misaligned.
Now comes H2, which indicates the flange on the wheels. The flanges prevent the tires from falling from the wheels of your vehicle.
#6. The Fraction 5/120
Now comes 5/120. The letter 5 indicates the number of lug nuts or bolts on the wheel. Most of the wheels have four to five bolts. So in almost all types of wheel, you will find either 4 or 5.
The number 120 determines the pitch circle diameter or more popularly known as PCD. The pitch circle is the diameter of the circle which passes the center of wheel studs, bolts.
The easiest way to measure is to measure the distance between the center of two studs adjacent to each other.
Then comes ET47 is the last number of the wheel markings, which indicates offset. The wheel offset is divided into three types, i.e., positive, negative, and zero offsets.
A positive offset is when the center of the hub mounting lies in front of the wheel centreline. If your vehicle has too much positive offset, there is a risk of tire failure or excess damage on the tire profile and rubbing of the tire. It can also make the tire unstable.
As per our example, ET47 indicates a positive offset.
A negative offset is the one when the center of the hub lies on the back of the wheel centreline. With too much negative offset, there will be more stress on the vehicle’s suspension system. Finally, it leads to damage of struts or other components.
Zero offsets are where the hub mounting surface lies in the center of the wheel. The measurement of offset is a bit tricky. The vehicle should have the correct offset. Otherwise, it will decrease the stability of the car.
You might also like to read : What Chemicals Will Soften Tires
What Are The Profiles That Are Now Not Used In Passenger Cars?
The profiles that are nowadays not used in passenger cars are as follows.
- Semi drop
- Flat based
- Drop Center
- 15-degree drop center
But, these profiles are still used in other vehicles like trucks, vans, and various agricultural vehicles.
Answers To More Questions About Wheel Markings
#1. What is the 7J rim size?
The width of the wheel is usually written beside the flange marking of the flange shape. The number 7 indicates the width of the wheel in inches. You should remember that the bigger the number, the thicker the wheel. The letter J indicates the tire bead profile.
#2. What does J mean in wheel size?
The alphabet J means tire bead profile. It is the marking that defines the wheel collar profile, which you should not ignore.
#3. What does 7J mean on a rim?
7J is the rim width. This factor is taken into consideration while installing a new tire for your vehicle.
You might also like to read : Is Rubber Cement Necessary While Plugging A Tire
Know The Meaning Of Wheel Markings To Make The Right Choice For Your Car!
Your vehicle moves on the road because of the wheels. So, the maintenance and correct alignment of wheels are pretty vital while driving your car.
Sometimes, the wheel bearings get damaged, and you are compelled to change the wheels. So you go to various tire shops to choose a new tire. But seeing different wheels and markings written over, there may puzzle you.
You need to understand the meaning of each term to maintain the vehicle’s stability while installing new wheels on your car. The tires and wheels should fit so that you can drive the vehicle safely on the road.
I hope this article will help you in making the right selections for your vehicle. Please don’t forget to share your suggestions for this article. I would love to read your suggestions in the comment section.