Installing larger tires on your Jeep Wrangler is a great way to increase your off-road performance. If you’re shopping around, looking to upgrade your tire-size, you’ve probably noticed that there’s a huge variety of sizes available, but you may be surprised to learn that the largest tire you can technically put on your Wrangler is not necessarily the largest tire you should put on your Wrangler.
What Is The Largest Tire You Can Fit On A Stock Jeep Wrangler?
The largest tire you can fit on a stock Jeep Wrangler without lifting it is generally 33 inches. However, keep in mind that, depending on the Wrangler model, a 33-inch tire may not function ideally, and it could do damage to your rig if you take it off-road.
There are a number of things you need to take into account before deciding on the largest tire you can put on a stock Wrangler. Otherwise, you run the risk of damaging your Wrangler. Consider the following before up-sizing:
- Year and model (i.e. generation)
- Suspension setup
- Axle ratio and engine size
- Center of gravity
- Intended application
Let’s take a closer look at the various things to consider when you install larger tires on your Wrangler.
Year and Model
Jeep Wranglers are separated by generations, and within the generations are several different trims. You can find the generation of your Jeep Wrangler based on the model year. The generations of Jeep Wranglers are as follows:
- YJ 1987 through 1995 model years
- TJ 1997 through 2006 model years
- JK 2007 through 2017 model years
- JL 2018 through the present model year
Why is this important? Because different generations and trims came with different stock tire sizes. For example, the biggest tire you can generally put on a stock TJ and still have full function is 31×10.50 – 15.
Larger tires on a TJ will likely rub at full flex and may cause other problems if you take the Jeep off-road. The 31×10.50 – 15 tires may also rub at full flex, but you can easily correct that by installing a washer or two on the steering stops.
The stock tire sizes on the JK generation of Wrangler were 255/75R17, 225/75R16 and 255/70R18. This is slightly bigger than the base stock tire size on the TJ, which was P225/75R15 in most cases. The Rubicon trims on the TJ generation and beyond come with larger standard tires than the other trims.
It’s always a good idea to check what your stock tire and wheel setup are before looking at larger tires. If you bought a used Jeep and aren’t sure of your equipment, you can go here https://www.jeep.com/webselfservice/BuildSheetServlet?vin= and enter your VIN after the = sign to find all the stock equipment on your Jeep.
The suspension on your Jeep is also a consideration. When you go off-road, you’ll often need maximum suspension flex to go over obstacles. Larger tires without a lift can inhibit suspension flex.
The other consideration is the condition of your suspension. If you have a high-mileage Jeep, you might have some extra play or slop in your suspension. Installing larger tires could result in sloppy movement and rubbing.
If you’re not sure about your suspension strength, then you may need to get a ride height measurement, which is usually done during an alignment. Weak springs can cause one corner to sag lower than the others. Without confirming this, you might end up with three tires that sit properly and one that rubs.
Axle Ratio and Engine
Your engine and axle ratio might also make a difference. For example, the TJ generation came with both a four-cylinder and six-cylinder engine. Part of running larger tires on a Jeep is being able to properly push them.
The four-cylinder engines on the TJ were known for having trouble pushing anything larger than the stock tires. Even with a lift, your Jeep might have a hard time. The four-cylinder engines on the JK and JL generations have more power than the TJ generation.
Yet another consideration when it comes to power and axle ratio is the type of tire. Mud tires are heavier than all-terrain tires and require more power to push. You can also check your axle ratio via the Jeep build page mentioned above.
For example, the more desirable 3.73 axle ratio was optional on TJ Sport and Sahara models, so you may not have it unless it shows on your build sheet.
Backspacing is the measured distance from the inside lip of the wheel to the hub mounting surface. More backspacing means that the tire is closer to the center of your Jeep. If you have a rim with zero or negative offset, then it will sit further out and allow for wider tires.
For example, a zero offset means that the hub mounting surface is at the rim’s exact centerline. This means that your backspacing is equal to half the width of the rim.
Center of Gravity
Why does the center of gravity matter? When you install larger tires on your Jeep, you’re increasing its center of gravity. A high center of gravity means that your Jeep is easier to turn over.
Jeep Wranglers already have a fairly high center of gravity compared to some other 4X4 vehicles. If you add taller tires but don’t increase the width of your rim, then you mainly achieve a Jeep that is more unstable. For example, if your stock rim is 15×7, you can generally install a 31×10.50 – 15 tire size.
However, you might want to consider getting 15×8 wheels to increase the backspacing and negative offset. Anything bigger than that tire size will likely require larger wheels.
As previously mentioned, larger tires on your stock Wrangler has a lot to do with the application. If you only intend to drive on the road without using the Wrangler’s famous maneuverability, you can probably squeeze even 35-inch tires on most rigs. Many JK owners say this is no big deal, while it’s a little tougher on a TJ.
On the other hand, if you intend to go off-road, you’ll need every bit of the full flex that a Wrangler is capable of. You don’t want your tires to rub or keep your Wrangler from flexing. In that case, you should either stick with stock tires, go one size up at most, or get a suspension or body lift.
The first place you’ll generally get rubbing when installing a larger tire is on the fender flares. If that happens, you can either trim the flare or install aftermarket flares that are designed to accommodate larger tires.
Your front flares are more friendly when it comes to this. Rear flares can be harder to work around if your tires rub on the body or the wheel well.
What’s The Largest Tire For Each Wrangler Model?
The JL Wrangler is the newest generation and it has larger fender and wheel well openings as well as an upgraded suspension. Running 33-inch tires on a stock JL is easy to do, and you can get 35-inch tires on a Rubicon trim with no problem.
JK Wranglers have three different stock tire sizes, and the stock backspacing is 6.25 inches. The stock sizes are 225/75/16 (29×9), 255/75/17 (32×10) and 255/70/18 (32×10). The largest diameter of tires for a JK is 33 inches. There might still be flex off-road, which could cause fender rub. Adjusting the steering stops with a few washers can fix this.
In general, the largest tire for a stock TJ with stock wheels and suspension is the 31×10.50 size. This usually allows for full articulation off-road and on-road. If you notice any body rub at full lock, you can easily fix it by installing a washer or two on the steering stops.
The YJ Wrangler can usually handle 30-inch tires on the stock rims without any issue. You can squeeze the 31×10.50 size on a YJ, but you’ll likely have to add more backspacing and the tires still might rub. It’s not recommended to go off-road with this setup without a lift.
Body Lift For Larger Tires
You don’t always need to get a suspension lift to accommodate larger tires. Body lifts are cheaper and easier to install vs. suspension lifts, and they can give you a few more inches to clear larger tires.
Every Jeep is different, so there’s no exact answer on exactly how big your tires can be. Owners of different generations often report different results with installing larger tire sizes. If you don’t intend to get a lift, the best approach is to be conservative with installing a larger tire size.