Roll in the Know: How to Choose the Right Wheels for Your 4x4Posted in How To: Wheels Tires on March 11, 2019
Swapping wheels from stock to aftermarket is one of the most common mods wheelers make to their 4x4s. Sometimes, it’s a simple cosmetic upgrade. Other times, it’s out of necessity due to a new lift or tire size. As the modern 4x4 becomes more diverse, so have the wheel-buying options. From beadlocks to massive 24-inch forged dishes, there’s something for just about everyone’s needs and wants.
While a certain look may draw you in, choosing the right wheel replacement for your 4x4 needs to go beyond the surface appeal. The wrong backspacing or diameter could create a laundry list of problems. For example, get the wrong backspacing and your tires might not clear your rig’s suspension components. Or, nab the wrong wheel diameter and your wheels might not fit over your rig’s brake calipers. All of these issues and more can be easily avoided with some research before you buy.
Each build application will have multiple factors to consider. The best thing to do is arm yourself with the right information to make sure your wheel investment is correct from the start. In this story, we’ll guide you through the wheel differences and get you the information you need to keep in mind throughout the wheel-buying process.
SteelAside from haggling on Craigslist for a used set of wheels, the least expensive new wheel set you can put under your 4x4 will be steel. These can often be a quarter of the price of an aluminum wheel of the same size. Beyond the lower price, another added bonus is that steel wheels are incredibly strong. And unlike a cast-aluminum wheel that might crack when going toe-to-toe with a blunt object off-road, a steel wheel is more likely to bend. This means you can often repair it on the trail with some gentle hammer persuasion. The major downside of a steel wheel is that they are heavier than a similar-sized aluminum wheel. While an extra 10 pounds per wheel might not seem like much, a few pounds at the wheel can be like adding a few hundred pounds in the vehicle. This may be a performance penalty that you’ll feel everywhere from the trail to the pump. There’s also the issue of rust. Frequent off-roading can peel back layers of paint and powdercoat, exposing the metal and creating a problem if not properly addressed. Overall, steel can be an excellent wallet-friendly alternative, but it depends on how and where you use them.
Cast AluminumNestled neatly between a basic steel wheel and a high-end forged wheel is the most commonly sold aftermarket wheel type—cast aluminum. Good, bad, or however you view it, these are largely made overseas. That’s not to say they are bad, but to give you a better understanding of the commonality of the majority. With the recent tariffs, prices have trickled upward. The big draw to cast-aluminum wheels is weight. Even in common 17- and 20-inch wheel diameters, a typical cast-aluminum wheel isn’t a major weight difference over the alloys that your truck may have rolled off the lot with. In some cases, they are actually lighter. With aluminum, you don’t have to worry as much about the environmental issues (rust) as you do with steel. However, cast-aluminum wheels can crack when hitting an obstacle, rather than bend like a steel wheel. Given that these are made from a casting, you often see the most wheel varieties and styles in a cast-aluminum wheel.
Forged AluminumThis biggest push onto the wheel scene over the past few years has been forged wheels. Forged wheels are at the top of the wheel food chain. They got there by having the weight savings of a cast-aluminum wheel and, thanks to the forged design, incredible strength. These are by far your most expensive wheel option. While they used to be targeted more toward the performance motorsports market, they are now a go-to for diesel truck enthusiasts. This is due to the strength of the wheel and load-carrying capabilities of modern 3/4- and 1-ton trucks. While we concede that forged is an excellent route to go for a tow rig, many off-road racers will opt for cast over forged. This is largely due to the idea that it’s easier to replace a broken wheel than a suspension component. For the average wheeler, forged is top of the line. If you’re looking at upgrading your tow rig’s wheels, forged-aluminum wheels are an excellent choice.
Backspacing & OffsetWhen looking at a given wheel, manufacturers will often list the backspacing and offset numbers. To determine a backspacing number, measure from the wheel’s mounting surface to the outer lip on the backside of the wheel. The lower the backspacing number, the farther outside of the wheelwell your tire will sit. For example, a wheel with 4 inches of backspacing is going to stick the tire outside of the truck more than a wheel with 6 inches of backspacing.
Offset is the distance from the centerline of the wheel to the wheel mounting surface. Offset is considered positive if it’s toward the outside of the wheel and negative when it’s toward the backside of the wheel. Between backspacing and offset, backspacing is typically the more critical of the two. A difference of just half an inch can make a big impact on determining if a given wheel will work for your 4x4.
From the factory, most wheels have a higher backspacing number to keep the tires tucked neatly inside of the wheelwells and reduce wear on items such as ball joints and wheel bearings. The backspacing your 4x4 will need greatly depends on if you are planning to add a suspension system and/or a larger set of tires. Thankfully, most suspension manufacturers do an excellent job of providing backspacing recommendations and even wheel diameter guidelines on their sites. The big thing to remember here is that a numerically low backspacing number can create additional leverage and strain on your frontend components.
Why Size MattersGone are the days of the 15-inch wheel. We miss them too, but it’s simply a reality we must face. While 17-inch-diameter wheels are most common among midsize truck and SUVs, larger 1/2-, 3/4-, and 1-ton trucks are commonly rolling off the showroom floor with 18s and 20s. As trucks and SUVs have become faster and a bit heavier over the years, manufacturers have added larger brakes to the equation. As such, wheel sizes have grown.
A larger-diameter wheel can equate to less sidewall. If you’re planning on hitting the trail, then that can be a bad thing. A 17x9 with a 35-inch-tall tire is going to have more sidewall that a 20x9 with a 35-inch tire. Having a few inches of sidewall cushion can be a major benefit. Primarily, this extra rubber cushion will be noticed when the tire is aired down. Dropping the tire pressure creates a secondary suspension of sorts, which improves ride quality and allows the tire to more easily conform to the terrain it’s crawling over. On the flip side, going with a larger-diameter wheel can help reduce sidewall deflection, which can improve handling on- and off-road. If you’re going to be hitting the road less traveled, we recommended keeping the wheel diameter smaller and the tire larger. If you’re going to be pulling heavy loads and rarely seeing dirt, so long as the tire and wheel are properly weighted for your vehicle, you can explore larger wheel options.
One thing to note here is wheel width. While 17x9 and 20x9 wheels sizes are the most common, we understand that you can get a much wider wheel. Doing so can create clearance challenges along with increasing strain on your frontend components. We prefer to keep our tire width a few inches greater that the wheel width. This helps with bead retention and keeps the sidewall of the tire in a more upright position.
Hub vs. Lug-CentricThe most common aftermarket truck wheels are lug-centric. This simply means the lug holes center the wheel rather than the hub bore. This allows aftermarket wheel manufacturers to create a wheel line with a larger center bore, ultimately allowing them to fit more applications. We’ve run both over the years, and as long as you keep your lug nuts tight, you shouldn’t have an issue. The biggest warning we will give you is to make sure the center bore of the wheel is large enough to pass over the hub. This is especially critical for 3/4- and 1-ton trucks with full-float axles.
Wheel FinishesYour wheel of choice will likely come with a polished, chromed, painted, or powdercoated finish. All have pros and cons. We like powdercoated wheels on our 4x4s, as they tend to require less maintenance and hold up well over time. When they do get a little worse for the wear, we can have them mediablasted and fit with a new coating. This will typically last us a few years.
Weight RatingsModern 4x4s can haul more weight inside and behind than ever before. As such, you’ll need to make sure your tire and wheel are load-rated for those demands. Wheel manufacturers list these numbers online, but you can also find it stamped inside of the wheel if you’re looking to buy something secondhand. Forged wheels will generally have the highest weight rating, but there are plenty of cast-aluminum wheels more than capable of handling modern payload demands for everything from a Jeep Wrangler to a Ford F-350.
Adapters & SpacersIf you like your stock wheels, there’s a good chance you can keep them, thanks to wheel spacers. When properly torqued and used correctly, a modestly sized wheel spacer is a perfectly fine option. If you have picked up a set of wheels with a different bolt pattern from what you have, you may be able to get a set of adapters that will allow you to use said wheel. Just be mindful of the backspacing, as wheel spacers/adapters will add to it quite a bit.
BeadlocksThere’s no question that lowering the air pressure in your tire will help with comfort and traction off-road. However, a traditional wheel offers little in bead retention, which can limit the amount of air you can release from the tire. With load ratings of E, D, and even F becoming more common, sidewalls are tougher than ever before. This is great for strength, but it requires you to let even more air pressure out when you hit the trail.
To ensure your tire doesn’t eject itself from the wheel at single-digit pressures, you can opt for a beadlock wheel. This is a wheel that’s designed to “lock” one or both tire beads in place. This is commonly achieved by sandwiching the outer bead of the tire between a wheel and a clamping ring. These are ideal for frequent wheelers looking to get the most performance and ride quality from their 4x4. However, beadlock wheels are a bit more expensive than a conventional wheel, and they’re typically not necessary for light trail wheeling. It’s also worth mentioning that your average beadlock is not DOT compliant, and some tire shops will not mount them. Since they use hardware to attach the bead, they also become a service item. We inspect and tighten our beadlock bolts every oil change.