5 Years Of Towing And Showing (Off) On Nitto Mud Grapplers

• May 12, 2023
• Story By
  Mike McGlothlin

What’s the best way to improve the appearance of one of the toughest-looking trucks ever produced by the Detroit machine? You add a Nitto Mud Grappler and a 20-inch chrome wheel at each corner and let the truck do the rest. Searching for the perfect way to cap off their ground-up, ’76 Ford F-250 Cummins-conversion project, Garret and Danielle Stewart settled on the most aggressive DOT-approved mud terrain on the market. Five years of joy-riding and towing trailers later, the Mud Grapplers are still along for the ride and will be for some time to come. “I had three sets of Mud Grapplers on my ’04 Dodge,” Garret tells us. “I love the look and performance of them.”

And while the Stewart’s primarily purchased the extreme terrain tread tire to set off the truck’s appearance, it didn’t mean they wouldn’t be put to work. Their load range E rating and exceptional load index makes them more than capable of handling the gooseneck trailers Garret often loads the old Ford down with. And if the audible turbo whistle and injector rattle from the 5.9L Cummins doesn’t garner enough attention, the low, one octave hum of the Mud Grapplers always seems to do the trick. Without question, Nitto’s large-lug mud terrain was the perfect tire for this vintage repower.

Ultimate Stance

The perfect companion for the perfect truck? The Stewart’s think so—and we think the extreme mud terrains fit the bill, too. Seeking an aggressive look for their Cummins-swapped High-Boy, Nitto Mud Grapplers got the call. Functionally, the Mud Grappler provides the kind of off-road overkill many wheelers have come to depend on, but mounting them under any vehicle immediately transforms it into a broad-shouldered Pitbull. The muscular, blue-collar appeal the Mud Grapplers offer the Stewart’s dent side is unmistakable.

A Stunning Workhorse

Six years in the making and originally hauled home in pieces, the Stewart’s slowly brought the former plow truck back to life. Even the bodywork was performed DIY-style in their home shop, followed by a superb paintjob from nearby Eureka Collision Center in Eureka, Illinois. At the heart of the build sits a ’96 Dodge Ram 3500 powertrain, which means a 5.9L 12-valve Cummins dwells beneath the hood. The P-pumped inline-six diesel is backed by the venerable NV4500 five-speed manual transmission, along with a part-time divorced NP205 transfer case.

37-inch Tires

Sized at 37x13.50R20LT, the Mud Grapplers under the Stewart’s High-boy represent one of the largest versions Nitto offers. And, like most sizes of the Mud Grappler, they offer an impressive, 21/32” of tread depth. Their outer diameter checks in at 37.05-inches while width measures a beefy, 14.13-inches. Beyond sizing, the Mud Grappler’s continued popularity means it enjoys high availability at tire retailers, not to mention availability in 21 different sizes spread across wheel sizes that range from 15-inches all the way up to 22-inches.

Aggressive Design, Slow To Wear

Nitto’s Mud Grappler possesses one of the most aggressive and functional sidewall lug designs of any DOT tire out there. And thanks to the Stewart’s High-boy primarily being bound to the pavement, they’ve suffered very little wear over the course of the last five years. As for the tread blocks, Garret tells us the wear they have endured has been minimal as well. “They do have a nice, smooth hum to them,” he admitted. “But that’s to be expected from an aggressive mud terrain like the Mud Grapplers.”

10-Ply Rating

They might be 37s, but the 37x13.50R20LT Mud Grapplers under the Stewart’s High-boy are much more than showpieces. In fact, they not only boast a load range E but an impressive load carrying capacity of 3,860 pounds per tire at maximum inflation pressure (65 psi). When tethered to a trailer, Danielle and Garret commend the Mud Grapplers for their stability, especially with 12,000 pounds in tow. Untethered, their ride quality is surprisingly comfortable. At least, as comfortable as a mud terrain can be aboard a solid axle, leaf spring-equipped pickup from the 1970s.

O.G. Dana 44 And Power Steering

Below the 5.9L Cummins sits the truck’s original (albeit rebuilt and equipped with 4.10 gears) Dana 44. However, the dated power ram assist was scrapped in favor of a power steering system that makes use of a ’78 model year gearbox. Here, you can also see the dual steering stabilizer that’s employed to help control side-to-side inputs from the 37-inch Mud Grapplers. Re-arched leaf springs (front and rear), 3-inch rear lift blocks and Bilstein 5100 series shocks all the way round highlight the extent of the truck’s suspension mods.

Completing The Look

The one area where the classic Ford fully breaks away from its roots exists in the 20-inch wheels the Mud Grapplers are mounted to. Fortunately, their aggressive styling aligns perfectly with the look of the hulking mud terrains. The 20x12-inch armor-plated (chrome finish) H101 Knuckle model rims come from Hostile Wheels and fall right into Nitto’s approved rim width for the Mud Grappler (9.5-inches to 12-inches). Like the Mud Grapplers, they too have held up very well after a half decade of use.