If you're looking to fit some beefy Super Duty rims on your half-ton pickup, you're going to need a set of 6x135 to 8x170 wheel adapters. It's a pretty common move for truck owners who want that heavy-duty look without actually trading in their daily driver for a massive F-250. Let's be real, the wheel options for the 8x170 bolt pattern are sometimes just more aggressive, and if you stumble upon a killer deal on some takeoff wheels from a newer Ford Super Duty, you're going to want a way to make them work.
It's not just about aesthetics, though. For a lot of guys, it's about the stance. These adapters aren't just changing the hole pattern; they're also acting as spacers, pushing your wheels out and giving the truck a much wider, more planted feel. But before you go bolting things on, there's a bit you should know about how these things actually function and what to look out for so you don't end up on the side of the road with a wheel passing you by.
Why swap from 6-lug to 8-lug?
The most obvious reason is the "cool factor." There is just something about an 8-lug wheel that makes a truck look like it means business. The 6x135 pattern is the standard for the Ford F-150 and has been since around 2004. It's a fine pattern, don't get me wrong, but the selection of deep-dish or heavy-duty style wheels is often much broader in the 8x170 world.
Another big factor is the secondhand market. You see it all the time on marketplace sites—somebody buys a brand-new F-250, immediately swaps the factory wheels for some aftermarket 22s, and sells the stock rims and tires for a steal. If you're rolling on an F-150 and your tires are getting bald, buying those takeoffs and a set of 6x135 to 8x170 wheel adapters can actually be cheaper than buying a fresh set of name-brand tires for your stock 6-lug rims.
The mechanics of a conversion adapter
You might be wondering how you can possibly fit eight studs into a space designed for six. It's a fair question. You can't just drill new holes; that would be a disaster for the structural integrity of your hubs. Instead, these adapters are usually two-piece units.
The first piece bolts onto your existing 6x135 studs. Then, a second plate (or the integrated outer half of the adapter) features the eight new studs in the 8x170 pattern. Because of this two-piece design, these adapters are almost always at least 2 inches thick. This is a crucial point because it means your wheels are going to stick out. You aren't going to get a "tucked" look with these; you're going for "poke."
Hub-centric vs. Lug-centric: Why it matters
When you're shopping around, you'll see terms like "hub-centric" and "lug-centric" thrown around. If you want my advice, always go hub-centric if you can find them.
A hub-centric adapter is machined to fit perfectly over the center bore of your truck's hub and has a lip that fits perfectly into the center of the new wheel. This ensures the weight of the truck is supported by the hub itself, not just the studs. Lug-centric adapters rely entirely on the studs to center the wheel. While they can work, they're much more prone to causing vibrations at highway speeds. If you've ever felt your steering wheel dancing in your hands at 70 mph, you know why you want to avoid that.
Material and build quality
Since these things are literally holding your wheels onto your truck, this isn't the place to try and save twenty bucks by buying some mystery-metal kit from an unverified seller. Most high-quality 6x135 to 8x170 wheel adapters are made from 6061-T6 billet aluminum.
Aluminum might sound "soft" compared to steel, but T6 billet is incredibly strong and used in aircraft construction. It's also much lighter than steel, which is important because you're adding "unsprung weight" to your suspension. Heavy adapters can make your ride feel a bit more sluggish and put extra wear on your shocks and ball joints.
The studs themselves are the other half of the equation. You want to make sure the adapter comes with Grade 10.9 or 12.9 heat-treated studs. If the studs are cheap, they can shear off under the torque of a heavy truck, and that's a nightmare scenario nobody wants to deal with.
Things to think about before you buy
Before you hit that "buy now" button, take a second to think about your current setup. Since these adapters add a minimum of 2 inches of width per side, your overall track width is going to increase by 4 inches.
- Fender Clearance: Are your tires going to rub the wheel wells or the bumper when you turn? You might need to do some trimming or look into a leveling kit to make room.
- Wheel Offset: Remember that the offset of the new 8-lug wheels also plays a role. If you buy wheels that already have a negative offset, combined with the adapter, they might stick out way past the fenders.
- Legal Stuff: In some states, it's actually illegal for your tires to poke out past the fenders without flares. It's worth checking your local laws so you don't get a "fix-it" ticket the first time you drive past a cop.
Installation tips for the DIYer
Installing 6x135 to 8x170 wheel adapters isn't rocket science, but you can't just zip them on with an impact wrench and call it a day.
First, make sure your hub surface is clean. Use a wire brush to get rid of any rust or debris. If the adapter doesn't sit perfectly flush against the hub, it's going to wobble. Once it's clean, I always recommend a tiny bit of blue Loctite on the factory studs—just to be safe.
Torque is the most important part. Don't guess. Use a real torque wrench and follow the manufacturer's specs (usually around 100-120 lb-ft for most trucks). After you've driven about 50 to 100 miles, you absolutely must take the wheels back off and re-torque the adapters. Everything settles a bit after those first few miles, and you'd be surprised how often they need a tiny extra turn to stay snug.
Maintenance and longevity
Wheel adapters aren't a "set it and forget it" kind of mod. Every time you rotate your tires or do a brake job, you should be checking the torque on the adapters. Also, keep an eye out for any signs of cracking or stress around the holes. If you live in a place where they salt the roads in the winter, the aluminum can sometimes corrode where it meets the steel hub. A little bit of anti-seize on the flat mating surface (not the studs!) can help prevent them from getting stuck.
Final thoughts on the swap
Switching to 6x135 to 8x170 wheel adapters is one of the fastest ways to completely change the personality of your truck. It opens up a world of wheel choices that the 6-lug crowd just doesn't have access to.
Yes, there are some trade-offs. Your wheel bearings might wear out a little faster because of the increased leverage from the wider stance, and you might have to trim a little plastic to keep the tires from rubbing. But if you buy high-quality parts, stay on top of your torque checks, and pick a wheel that fits the vibe of your rig, it's a killer upgrade. Just take your time with the install, do it right, and enjoy the look of those 8-lug monsters on your F-150.