Nitto Trail Grapplers K-Spec Tires - 4-Wheel & Off-Road Magazine

Fred Williams Brand Manager, Petersen’s 4Wheel & Off Road

When Nitto offered us the chance to test a set of its new 40-inch Trail Grappler race tires we were a little concerned. These are unique race tires. They have a special rubber compound for added traction, they have a top-secret carcass that holds up great to trail abuse, and they are in a size not currently available from Nitto, 40x13.50R17. So why would we want to test a tire that no one else but Nitto-sponsored racers could get? Then Nitto came halfway and told us that this same tire size would eventually be available in the Trail Grappler for public purchase. We agreed to test them, even if we felt the rockcrawling traction may be off the record, per se.

super Trail Grapplers ultimate Adventure Jk Photo 40723577

After a long hot summer of testing them we are now really concerned, because we really like these tires. They ride great both on- and off-road, they are tough as heck, and as for that elusive race compound traction, it really feels like we are cheating in the rocks.

super Trail Grapplers ultimate Adventure Jeep On The Rocks Photo 41273005 We bolted the 40-inch Trail Grapplers onto a set of Mickey Thompson Classic Lock black wheels with Inner Air beadlocks. We really like the look of these wheels, but the outer faux-beadlock ring (which we had sandblasted the black paint off of) took serious abuse during the Ultimate Adventure. The Inner Air beadlocks are difficult to install, and we actually had some issues with two rims slowly leaking around one of the Inner Air valve stems, but they worked well at locking the bead in place at low tire pressures.

Official word is that the tires Nitto will be offering to the public will look the same as these, but with a few changes. We expect them to arrive in early 2013.

PhotosView Slideshow Since these tires are a special race tire there isn’t much we can tell you about their composition. We do know that the public version will have the same construction as most other Trail Grapplers with similar load ratings. If the public version is offered in a Load Range C, as our competition tires are, then they will likely have a tread constructed of two steel, three polyester, and two nylon plies, with a three-ply polyester sidewall. The sticky rubber compound is awesome in the rocks, allowing us to crawl obstacles with nary a tire slip. We have had great performance from the other Nitto tires, such as last year’s UA tire the 40-inch Mud Grappler, but this soft rubber compound definitely outperforms the standard rubber. However, Nitto only offers this as a race compound since it doesn’t have the wear longevity often demanded by customers. On the road the Nitto Trail Grappler is by far one of our favorite mud-terrain tires. Unlike its cousin the Mud Grappler, the Trail Grappler is not extremely loud. It’s not silent, but the noise level is much more livable. The tires handle well, and we didn’t even balance our 40s before going on a long road trip. The tires had no noticeable shakes or vibrations and wore evenly over a few thousand miles. On-road pressure was often run in the mid-30s psi to keep the tires from overheating. Mud really showed the dynamic ability of the Trail Grappler tread design. They would clean quickly and allow our test Jeep to keep pulling forward except in only the worst-case scenarios. The tires are heavy, but we were still able to get them spinning with just a V-6 engine and 5.38 gears. The Trail Grapplers are tall and wide enough to float over soft sand. Though aggressive, they didn’t dig in. This is a tire that works well in a variety of terrain and, with a variety of load ranges available, could work on different size 4x4s. The 40-inch competition Trail Grappler was developed for grueling Ultra Four racing, such as King of the Hammers. These tires have helped drivers such as Nick Nelson earn victories like his class win at the Vegas to Reno off-road race. The Trail Grappler is a good all-around tire, and over two years of Ultimate Adventure trips on Nitto rubber we have had zero punctures. That is a testament to the abuse they can take.

Specifications
Make & Model: Nitto Trail Grappler K-Spec
Size tested: 40x13.50R17
Type: Radial
Load Range: C
Maximum load (lb): N/A
Tread: N/A
Sidewall: N/A
Approved Rim Width (in): 81⁄2-11
Tread depth (in): 11⁄16
Tread width (in): 101⁄2
Section width (in): 131⁄2
Overall diameter (in): 40
Weight (lb): 107
Sizes available (in): Race spec 40, standard compound 31-38, 40 available in early 2013