Words by Patric Fransko

RAYS’ D108 from their off-road lineup is built to look aggressive and back it up with motorsport-derived traction and weight tech.

For four decades, RAYS has built its name on the racetrack. The Japanese manufacturer behind the legendary TE37 — a wheel so influential it basically defined the modern lightweight forged aesthetic — has spent generations refining alloy wheels for circuit racing, drift, and time attack, leaning on technology developed in Formula 1 and other top-tier motorsport. So when RAYS decided to go off-road, the natural question was whether that pedigree would actually translate to the trail. The D108, the newest release in the RAYS Offroad Wheels lineup, is the company’s clearest answer yet.

Marketed under the tagline “DO WILD,” the D108 is positioned as the follow-up to RAYS’ earlier off-road efforts, and it’s built specifically for the modern wave of overlanding and off-road-sport trucks and SUVs running wide fenders and aggressive stances. If you’ve been paying attention to what RAYS has been doing outside its home turf of grip circuits, this wheel continues that trajectory — but with a design language that’s unmistakably its own.

Design Language: Deep Dish Meets Function

The D108’s visual signature is a deep rim paired with a flat, wide 8-spoke face — a look that reads as minimal from a distance but rewards a closer inspection. RAYS hollowed out the backside of each spoke, a construction choice pulled straight from motorsport thinking: shed rotational mass everywhere you can without giving up structural integrity. On a street wheel, that kind of weight-shaving is mostly about lap times.

On a trail wheel, it has a more practical payoff — every pound removed from unsprung, rotating mass is a pound your suspension and drivetrain don’t have to work as hard to manage, which matters over a long washboard road or a technical rock crawl just as much as it does on a road course.

The D108 is a cast one-piece wheel rather than forged, which is worth noting for buyers comparing it against RAYS’ premium racing lines. Casting keeps cost more reasonable while still meeting RAYS’ engineering standards, and every D108 clears the JWL and JWL-T +R Spec 1 safety certifications — Japan’s rigorous wheel testing standards that go beyond what’s required in most markets. It’s a sensible trade-off for a wheel aimed at trucks that need durability and a fair price point more than they need forged-wheel weight savings.

Knurling Finish: A Small Detail With Real Traction Payoff

One of the more interesting engineering touches on the D108 is easy to miss in photos: a knurling finish machined into the bead seat, where the tire meets the wheel. Under hard acceleration, braking, or the kind of torque spikes that come from articulating over uneven terrain, tires can slip slightly against the wheel bead — enough to throw off wheel balance or, in extreme cases, shift valve stem position.

The knurled texture increases friction at that interface, reducing slippage and helping keep the tire seated exactly where it should be. It’s a detail borrowed from high-traction racing applications, repurposed here for exactly the kind of high-torque, low-traction scenarios overlanders deal with on loose dirt, sand, or rock.

Sizes, Colors, and Fitment

The D108 currently ships in 16-, 17-, and 18-inch diameters, giving builders a fairly wide window to match tire size and gearing preferences. Two finishes are available: a stealthy Matte Black (BZZ) and a warmer Dark Bronze (JZZ), both of which lean into the rugged, understated look RAYS is going for rather than anything flashy or chrome.

Bolt patterns span 5×139.7, 6×139.7, and 6×114.3, covering a solid chunk of the popular midsize and full-size truck and SUV platforms overlanders already run. Widths range from a modest 6 inches up to 9 inches, with offsets swinging from 0 to +52mm depending on the size — enough range to dial in flush fitment under stock fenders or push wheels out for a more aggressive look under armor and flares. Load ratings scale with size, topping out at 955 kg (2,600 lbs) per wheel on the larger fitments, which is plenty for most loaded overland builds.

RAYS specifically called out fitment testing on the Nissan Frontier, releasing a companion video showing the D108 mounted on the truck and noting caliper clearance confirmation for the 18x8J, 6×114.3 offering. That’s a useful data point if you’re running a Frontier and shopping wheels, though as always, it’s worth confirming clearance against your specific brake package before ordering, especially if you’ve upgraded rotors or calipers.

Pricing and What’s in the Box

Pricing runs from roughly ¥50,000 for the 16x6J up to ¥68,000 for the largest 18x9J fitment — reflective of RAYS’ Japan-market pricing, so expect variation once the wheels move through distributors and retailers stateside. Each wheel includes a RAYS sticker, an air valve, and — depending on bolt pattern — a center cap. It’s worth double-checking with your dealer exactly which cap comes standard for your specific fitment versus which one is an optional add-on, since RAYS’ documentation varies coverage slightly by bolt pattern.

Where the D108 Fits in a Build

The honest pitch here isn’t that the D108 reinvents the off-road wheel category — it’s a cast, JWL-certified wheel with a handful of thoughtful, motorsport-derived details bolted onto a genuinely good-looking design. If you’re chasing the absolute lightest wheel money can buy, RAYS’ forged lines (or competitors’ forged off-road offerings) will get you there at a higher price. What the D108 does well is bring real engineering thinking — weight reduction where it counts, bead traction where it matters, and a design that doesn’t scream for attention — to a segment that’s increasingly crowded with wheels that look tough but don’t offer much beyond the look.

For builders already eyeing wide-fender platforms and wanting something that reads as purposeful rather than purely aesthetic, the D108 is a strong option to have on the shortlist. And given RAYS’ track record of iterating quickly on its off-road line, it’s reasonable to expect this design language — deep dish, hollow spoke backs, knurled bead seats — to show up again as the DO WILD series expands.

RAYS D108 wheels are available through RAYS dealers; sizing, pricing, and fitment details are subject to change, so confirm current specs with your dealer before ordering.