BMW M340i Bolt Pattern: G20 Wheel Fitment, Sizes & Offset Guide

Introduction

The BMW M340i Bolt Pattern is 5×112, with a 66.6 mm center bore and M14×1.25 wheel bolts, where 5×112 refers to the number of lug spaces around the circumference of the wheel: a 5-bolt pattern with a diameter of 112mm, but this is not the only spec to fit your BMW.

BMW M340i Bolt Pattern & Fitment Specs at a Glance

The BMW M340i wheel bolt pattern on the G20 platform is 5×112. It is the only bolt pattern shared by the BMW M340i among its 11 configurations. The full wheel package comes with a broad range of equipment and market variations for the BMW M340i. For those strategically sourcing BMW M340i wheels, the following are the relevant mounting specs:

The bolt pattern represents the wheel mounting-hole arrangement. The center bore, hardware, wheel dimensions, and clearance determine whether that wheel is a fit for the vehicle. So, never fit a 5×112 wheel in an M340i without a proper check of the wheel’s full specifications.

G20 M340i OEM Wheel & Tire Fitment

BMW’s tire documentation also confirms these 18- and 19-inch tire dimensions for the G20 platform/vehicle.

What is noteworthy about the M340i wheels is that factory sizing isn’t just a choice of diameter. They should also provide information regarding wheel width and tire dimensions. For instance, BMW documentation suggests that the M340i could have varied front and rear widths. By this, an aftermarket wheel should be compared with the relevant OEM configuration, rather than being chosen based on diameter.

In fact, the exact factory combination should be checked against the model year, market, drivetrain, and equipment of the vehicle. Thus, a 2020 BMW M340i and a later G20 are not automatically going to have the same factory wheel packages, just by belonging to the same generation.

For the distributors and the retailers, this baseline of OEM could be helpful while building the fitment data. The wheel and tire configuration, as a whole, should be recorded instead of listing the product just as G20 compatible. With that, the customer could get through the ambiguity when comparing BMW M340i rims or evaluating an aftermarket replacement.

M340i Center Bore & Wheel Hardware

Aside from the BMW M340i Bolt Pattern, there are other considerations to make. The G20 M340i has wheel bolts fashioned with M14×1.25 threading and a 66.6 mm center bore. These dimensions refer to the separate components of the wheel-to-hub connection and should be checked separately when selecting BMW M340i wheels.

To explain further, 5×112 specifies the bolt pattern, 66.6 mm indicates the center-bore size, and M14×1.25 describes the wheel-bolt thread. A PCD wheel can still require further verification – if the centre bore/ hardware seat/ bolt spec is mismatched, it cannot be used.

How to Read an M340i Wheel Specification

The term ‘5×112’ alone is not going to help you if you are comparing M340i wheels. Instead, you should always read the complete description or specification. The information in ‘19×8.5 ET35 | 5×112 | 66.6’ is contained in five parts.

Here, 19 denotes the diameter of the wheel in inches; 8.5 denotes the width of the tire; ET35 denotes the positive offset, which tells where the mounting face sits relative to the centerline of the wheel; 5×112 denotes the PCD; 66.6 mm is the center bore dimension.

Same PCD ≠ same fitment

If you have 19×8.5 ET35 and 19×9.5 ET25 wheels, both of them can use the M340i BMW’s 5×112 mounting pattern, but the M340i wheels are not located similarly on the car. If the second M340i wheel is 1 inch wider and has a reduced offset, then its interior and exterior positioning also differ.

That’s particularly valid when you compare M340i aftermarket wheels from alternative producers. Two wheels with equal diameter, breadth, offset, and PCD can have a dissimilar spoke and barrel shape. So, a comprehensive fitment check should check the manufacturer’s true wheel drawings, or convey vehicle-specific fitment data wherever available.

M340i Wheel Width & Offset: How They Affect Fitment

Width and offset are closely related when it comes to BMW M340i wheels. Changing either one of those dimensions changes where the wheel sits inside the G20 wheel well. The goal isn’t only to make the wheel wider because you need enough room on both the suspension and fender side, and still wish to retain proper tire and brake clearance. A wider wheel will give more room for wider tire applications, but it will also have a lateral space requirement.

Wheel Width

When you make a wheel wider, its inner edge moves closer to suspension components, and the outer edge moves closer to the fender. The section width of the tire will increase the space requirement further.

That’s why two M340i wheels of the same diameter can give very different fitment results. Width has to be evaluated together with offset and the intended tire size.

Offset

For the G20 BMW M340i, an offset change without noting the width of the wheel can cause a fitment that is uneven. Moving the wheel outwards provides additional fender clearance for the inner side. An inward movement produces the exact opposite condition. An additional change depends on the size of the tires and the shape of the sidewall.

Brake Clearance

Wheel diameter alone is not an indication of brake clearance at all. A wheel’s spoke profile, the inner barrel diameter, and mounting geometry can determine whether or not spokes clear the caliper of the brake hardware.

And for the proper M340i aftermarket wheels and compatibility, this is the sequence to evaluate their fitment accordingly: PCD → center bore → width → offset → brake clearance → suspension and fender clearance → tire → load rating → hardware. This sequence prevents a correct BMW M340i Bolt Pattern from being mistaken for complete wheel compatibility.

18-, 19- & 20-Inch M340i Wheels: Which Size Makes Sense?

The right selection of M340i wheels between the 18, 19, and 20 inches will not just be down to aesthetics. The diameter of wheels changes the amount of tyre sidewall, which affects comfort, road impact protection, and the vehicle’s character. The correct selection of wheels will be based on how you use your M340i and the wheel-and-tyre combination.

18-Inch M340i Wheels

18-inch alloy wheels will offer a greater amount of tyre sidewall compared to larger diameters when paired with tyres with similar profiles. More sidewall will offer a more forgiving ride on bad surfaces and offer better protection from sharp impacts. They can be practical while driving daily, especially when road conditions are worse and you can find different designs and options of wheels for BMW here.

The official G20 documentation from BMW lists the configuration for an M wheel of 18 inches with 7.5J front wheels and 8.5J rear wheels, paired with 225/45 R 18 front and 255/40 R 18 rear tyres.

19-Inch M340i Wheels

Everyone knows that 19-inch wheels are a great middle ground. They are efficient because they have some sidewall, and at the same time, they have a performance appearance that no one can ignore. BMW recommends the 19-inch M wheels. They have some wide options: 8J for the front, 8.5J for the rear.

Hence, 19-inch M340i rims from the factory offer a realistic starting point when considering aftermarket choices. The selection of wheels and tires available for the G20 is vast, with the general proportions in the area around the original design of BMW

20-Inch M340i Wheels

20-inch alloy wheels cut back on the available tire sidewall compared to the smaller diameters.

When it comes to the BMW M340i rims, we should think of 20-inch wheels as a fitment choice, not just an automatic upgrade. We should still make sure that the wheel’s width, offset, tire specification, or brake clearance are verified. BMW’s published G20 documentation does not show a single 20-inch M340i configuration, so we should be careful about using any of the aftermarket listings as a substitute for the factory specs without any confirmation.

Square vs. Staggered M340i Wheels

When you choose between M340i wheels in a square and staggered set, the front-wheel and rear-wheel positions will be configured differently. Squared setups are those that use similar wheel and tire dimensions at each one of the four corners.

On the other hand, the staggered setup uses different dimensions for the front and the rear, often using a more extended racing setup at the rear. BMW’s G20 documentation includes mixed front and rear wheel widths on M340i builds, so the staggered fitment has clear factory relevance.

What About M340i xDrive?

More than a matched wheel diameter, an xDrive M340i with a staggered set-up requires a compatible front and rear tyre pair. Check the rolling circumference for the vehicle and drivetrain. Please do not apply a rule of thumb to each tyre combination. What can additionally affect the result are the tyre model, size, wear, and actual dimensions of the tyres used.

Can Other BMW Wheels Fit the M340i?

Some BMW aftermarket wheels from other models might seem to be right for the M340i just because they have the same 5×112 mounting pattern. But those don’t become direct-fit wheels.

This is very important when you are sourcing wheels for BMW across different models. Older BMW applications generally had 5×120, so those wheels shouldn’t be considered as direct-fit options for the G20 just because they are BMW wheels. The same goes for newer 5×112 applications.

The same careful approach should be taken when considering M3 wheels. M3 and M340i may have the same mounting dimensions, but bodywork, sports brakes, wheel width, and clearance changes are likely to play their roles. One must always validate a wheel for a specific vehicle, instead of merely approving it by the PCD.

For all distributors and retailers, the practical rule is not to call a wheel “G20 compatible” based on the BMW M340i bolt pattern. Get the complete fitment specification before listing or ordering a wheel.

Cast vs. Flow Formed vs. Forged M340i Wheels

For the BMW M340i wheels, the wheel’s construction matters mostly when you’re comparing the wheel’s weight, performance priorities, budget, and also the wheel’s customization. Irrespective of whether a wheel is cast, flow-formed, or forged, a wheel you’ve specified correctly needs to match the M340i application.

BMW M340i Wheel-Fitment Checklist

For distributors and retailers, treat M340i fitment as a pre-order verification record rather than merely a PCD check before distributor or retailer approval of M340i aftermarket wheels.

Common BMW M340i Wheel-Fitment Mistakes

The most common M340i rim mistakes stem from considering one specification as assured complete fitment. The M340i bolt pattern verifies that the mounting pattern is correct; it doesn’t assured fit the brakes, tires, clearance, or any other differences in vehicle configuration.

Regarding the retailer, it’s safer to verify the complete application before listing or ordering M340i aftermarket wheels, rather than fully approving a product based on a single matching specification.

Conclusion

BMW M340i Bolt Pattern is 5×112; this is only the beginning of the right fitment decision. You need to know not just methods to correctly measure BMW M340i bolt patterns, but also the following data. Center bore, hardware, wheel dimensions, offset, brake clearance, tires, and vehicle configuration should match. For retailers and distributors, don’t risk incorrect applications, returns, and installation problems; check the complete specification before ordering M340i wheels.