We’ve written extensively about the Subaru WRX and numerous questions you can have about this car. Today, we will talk about the information you need to have to select the correct new tires or rims for your Subaru. Specifically, we’ll take a look at the bolt pattern for each generation. Let’s start with a quick answer:
All generations of the Subaru WRX and WRX STI have a bolt pattern of 5×4.5 (5×114.3mm), a center bore of 2.20 inches (56.1mm), and five lug nuts with a thread size of M12 x 1.25 that need to be tightened with 88.5 lb-ft (120Nm) of force.
However, that certainly doesn’t tell the whole story. Below we’ve outlined the bolt pattern in more detail for each generation. We also discuss what lugs/bolts are used precisely, the exact diameter of the center bore hub, and the torque specifications of the bolts. Finally, we also have information about each engine type’s exact tire size and rim size. You should know precisely what you can and cannot buy this way. Read on!
Also read: Subaru WRX Transmissions: Overview, Problems, Fluids
Wheel Fitment Specifications Per Generation
To fit a wheel properly on your Subaru WRX (STI), you’ll need to know more aspects than just the bolt pattern. Below we’ve outlined all the factors you should be aware of for each generation of the WRX (STI). These include: center bore diameter, wheel tightening torque, whether lug nuts or bolts are used, and the thread size of the bolts.
We also want to clarify that the below-listed specifications are the same for all models within that generation. The WRX, of course, comes in different trim levels and engine options. However, these bolt patterns, lugs used, and torque specifications do not change for other models within a generation.
Furthermore, we also listed the exact tire and rim size used with each engine option to give you a precise idea of what tires you can and cannot buy.
2018 – Present
- Subaru WRX 2.0T (268 hp) has a standard tire size of 235/45R17 or 245/40R18 and a standard rim size of 8Jx17 ET55 or 8.5Jx18 ET55.
- Subaru WRX 2.0T (268 hp) has a standard tire size of 235/45ZR17 and a standard rim size of 8Jx17 ET55.
Also read: How Many Miles Can A Subaru WRX Last? (Answered)
Subaru WRX STI
2021 – Present
- Subaru WRX STI 2.5T has a standard tire size of 245/40R18 or 245/35R19, and a standard rim size of 8.5Jx18 ET55 or 8.5Jx19 ET55.
2018 – 2020
- Subaru WRX STI 2.5T has a standard tire size of 245/35ZR19, and a standard rim size of 8.5Jx19 ET55.
2015 – 2017
- Subaru WRX STI 2.5T has a standard tire size of 245/40ZR18, and a standard rim size of 8.5Jx19 ET55.
Also read: Subaru WRX Towing Capacity: Can It Tow A Trailer, Boat, or Jet Ski?
Retightening The Bolts
As said before, most generations of the Subaru that we discussed have five lug nuts. These need to be secured in a specific way when you mount the wheel to the car again. This information is stated in the owner’s manual, but we’ve gone through the effort of instructing you here. Subaru advises you to bolt these nuts in the way that’s shown below. You have to follow a crisscross pattern.
You do this by tightening all the nuts with a wheel wrench first. I like this wrench on Amazon in particular because it fits all bolt sizes for cars and trucks and is quite affordable. Please make sure only to tighten them halfway; otherwise, you’ll run into problems.
In the second round, you tighten them with the wheel wrench to the appropriate lbs-ft or Nm that we’ve stated earlier. Please note that the newest generation of the Subaru WRX (STI) needs to have the bolts tightened to 88.5 lb-ft.
It’s expected that your wheel also have a center cap or cover. These need to be secured in the same pattern. Please tighten them first-hand snug with your hands. Then, use the wheel wrench to tighten them another one-quarter turn.
It’s also important to check if the lug nuts are still secured after 30 miles (48 kilometers). Please make sure they are all in place and still tightened with the proper force. If not, tighten them again and recheck. If this keeps happening, you’ll need to replace the wheel.
When Or Why To Rotate/Change Tires
Suppose you’re changing your tire. You also need to know when to change or rotate it precisely. Let’s first talk about changing your tires. Tires usually last around 60,000 – 75,000 miles or 4-5 years. After this period they need to be replaced. Sometimes this happens earlier, and therefore, it’s a good idea to keep an eye on the tread wear indicators. These are shown in the image below. These indicators show when the tires have only 1.6 mm (1/16 in) or less tread remaining.
Another occasion when you’ll need to take off your tires is when you’re rotating them. In the owner’s manual of the WRX (STI), it’s said that this needs to happen every 7,500 miles or 12,000 kilometers. It’s advised you rotate the tires in the exact way that’s shown below. The front tires are moved to the back, and the front tires move crisscross to the front.
Hi! My name is Stefan; I’m the owner and lead writer at TheDriverAdviser.com.
I’m an active writer on this blog myself, as well as a novice car mechanic. For the really technical stuff, I find writers with experience as a mechanic or who have studied mechanical engineering.
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