Chat with us, powered by LiveChat What Are The Differences In King Of The Hammers Race Classes | Quadratec Skip to main content
Blog

by Matt Konkle
Torque Editor-in-Chief


The vast Mojave Desert isn’t just claimed by Jeep vehicles during this year’s King of the Hammers event. There is everything from utility terrain vehicles to fully-loaded Jeeps and trucks taking on everything the desert, and surrounding rocky enclaves, can offer.

But when you look at each race during the week, you’ll see designations on vehicles that may seem strange unless you are fully indoctrinated in the Ultra4 Racing world.

So, for those who do not know, and are planning to follow along for KOTH week, here are some of the class differences you’ll need to understand.

4400: Unlimited Class

This is the original unlimited class that started the King of The Hammers years ago, and each vehicle is heavily modified and engineered to compete during the main King of The Hammers race. Drivers have to earn a spot to compete in King of The Hammers and their rides are not limited on tire size, engine or chassis design, other than to meet the safety requirements for the class. They also must have a transfer case, four-wheel-drive system and can utilize either a straight axle or independent front suspension.

4500: Modified Class

This class has been racing in ULTRA4 since 2012 and is one of the three classes that can compete during the Every Man Challenge. Currently, these do not have to qualify to race in the EMC race during KOTH week. This class is marked by vehicles that have a modified OEM Chassis or OEM Style Chassis, 2 -2.5 inch diameter shocks per corner, mechanical steering and 37-inch United States Department of Transportation approved tires.

4600: Stock Class

This class has also been racing in ULTRA4 since 2012 and is one of the classes eligible to take part in the Every Man Challenge during KOTH week. Currently, these vehicles do not have to qualify to race in the EMC. This class is marked by using a stock frame, factory engine and transmission, 35-inch DOT approved tires, 2.5-inch diameter shocks per corner and mechanical steering.

4800: Legends Class — Trophy Class

'

This class has been racing in ULTRA4 since 2014 and is one of the 3 classes eligible to race in the EMC during KOH week. These vehicles do not have to qualify to race in the EMC, and the class itself is one of the fastest-growing in ULTRA4 as older ULTRA4 cars can enter as long as they meet the requirements. Vehicles in this class can only have front-mounted engines, contain two seats side by side, utilize only a single shock per corner, use maximum 37-inch DOT non-sticky tires and only have solid axles installed.

While these classes represent the majority of full-size vehicles, KOTH week also features many UTV and full-size truck classes, including stock, pro modified, open and unlimited.

Top Jeep Articles

  • June 3, 2026
  • 5 min read
Congratulations, You’ve Joined The Wrangler Family: Now Check These Things First
From square-headlight YJs to high-tech JLs, here’s the real-world used Wrangler inspection guide every new Jeep owner should read before the next trail ride, road trip, or late-night parts order.
READ MORE
  • May 29, 2026
  • 5 min read
Five Reasons A Jeep Bumper Should Be Your Next Upgrade
Rugged, durable aftermarket Jeep Wrangler bumpers offer much more than just a safety upgrade over the factory version — making them ideal for an inaugural upgrade option.
READ MORE
Red Wrangler on a white background
  • May 27, 2026
  • 5 min read
Jeep Bumper Questions Answered: Everything Wrangler Owners Need to Know Before Upgrading
Not all aftermarket Jeep bumpers are created equal. So if you are in the market for a new one, here are some common-sense answers.
READ MORE
Green and black Jeep against a rocky background
  • May 26, 2026
  • 4 min read
Jeep Wrangler Scrambler Details: Future Performance & Plans
New reports on Stellantis’ long-term roadmap suggest Jeep is preparing a dramatic expansion of its off-road and performance lineup, including a revived Scrambler pickup, the return of SRT models, and a gas-powered version of the upcoming Recon.
READ MORE
  • May 25, 2026
  • 5 min read
Jeep Death Wobble Q&A: Causes, Symptoms, Fixes and How to Prevent It
Learn what death wobble is, why it happens on solid-axle Wrangler and Gladiator models, and the exact components to inspect for a safe, lasting repair.
READ MORE
  • May 19, 2026
  • 4 min read
Memorial Day Jeep Adventures Start with Preparation, Responsibility, and the Right Gear
From trail recovery gear and camping essentials to responsible off-road practices, here’s how Jeep owners can prepare for a safe, adventure-filled Memorial Day weekend while helping protect public lands for future generations.
READ MORE
White Jeep Wrangler with a colorful background
  • May 18, 2026
  • 3 min read
Could Jeep’s Next Electrified Off-Roaders Really Come From China?
A new Stellantis partnership with Chinese automaker Dongfeng could shape the future of Jeep EV production, raising questions about global manufacturing, electrification, and what it means for the brand’s American identity.
READ MORE
  • May 13, 2026
  • 3 min read
Jeep Debuts Canada-Exclusive Wrangler Rocky Mountain 392 With HEMI V-8 Power
The latest Twelve 4 Twelve special edition gives Canadian Jeep fans a Wrangler 392 packed with V-8 performance, exclusive styling details, and open-air capability.
READ MORE