We feel pretty lucky right now since we are some of just a few people who were able to get our hands on a set of the new 42-inch Goodyear MTRs. The new MT/R Goodyear with Kevlar has really hit a homerun with these true 42s that measure every inch of their labeled diameter and stick to rocks like chewing gum.
The original MT/R spent quite a few years as a popular tire with an unchanged tread design, but this new version has all the impressive traits of the last MT/R and more.
The tread has been separated into four ribs that follow the circumference of the tire and seem to give it a directional tread pattern, even though it is not directional. The tire, when fully inflated, puts the majority of weight on the two centered ribs. One of these ribs has much less tread void than the other ribs to give a smoother rolling surface for on-road and high-speed off-road travels.
We tested the 42-inch MT/Rs on a new four-door Jeep JK Wrangler, but it has been outfitted with so many aftermarket upgrades that this vehicle weighs more than some fullsize trucks. Did we like the results? Oh yeah.
Overall Impressions
To say that we enjoyed testing with this tire would be an understatement. Not only did the Goodyear 42-inch MT/Rs surpass our expectations in the dirt, but also on rocks too. The tire did an amazing job of sticking to obstacles and pulling itself up onto things that other tires would just sit and spin on.
The sidewalls proved to be very flexible, even with the added Kevlar, and throughout all the testing, we never put serious damage into any of them.
The highway ride was not the best we've ever had, but the tire is still more than suitable for driving on every day and we were more than happy to sacrifice a little on-road performance for the awesome off-road performance.
Specs As Tested
Make/Model:
Goodyear
Mounted On:
17x10 Walker Evans Beadlocks
Size On Sidewall:
42x14.50R17
Load Range:
C
Max Load:
3,195 pounds
Tread Depth:
22/32
# Plies in Sidewall:
2 polyester plies, 1 kevlar ply
# Of Plies In Tread:
2 polyester plies, 2 steel plies, 1 nylon ply
Weight Of Tire:
92 pounds
Measured Diameter Unloaded:
42 inches
Measured Width Unloaded:
14.50 inches
Measured Tread Width:
11.75 inches
Available Sizes:
30-42 inches
Available For:
15- to 20-inch wheels
 The 42x14.50R17 measures out...  The 42x14.50R17 measures out to be a true 42-inch-tall tire. We measured it next to some other 40-inch-and-bigger radials and the MT/R definitely held true to the labeled size better than its competitors.
The new MT/R has Dupont Kevlar built into its carcass to give a 35-percent stronger sidewall than its predecessor, but the sidewall still remains very flexible. The wraparound tread offers extra sidewall protection as well. Its four-rib design gives a great ride in the dirt and the high void ratio of three of the tread ribs give a ton of bite in the dirt and the rocks. The silica rubber compound is also very sticky and really grabs, but we don't know how well these will wear after 20,000 miles. Check back for a long term update in an upcoming issue. | 
10 psi | 
5 psi |
 The tread blocks are squared...  The tread blocks are squared off and are very aggressive. You can see in the picture that the majority of the vehicle's weight is put on the two center tread ribs when the tire is fully inflated. |  High Speed Dirt Making some...  High Speed Dirt
Making some high-speed passes through whoops and on flat roads gave us confidence that these tires held forward motion well, and didn't want to slide out when we started going fast. The parallel ribs help give good lateral traction and kept us in control at high dirt speeds. |  Rocks This tire absolutely...  Rocks
This tire absolutely shined in the rocks, and if you're looking for the 42-inch versions, then we're guessing that this is what you're going to be focusing on during your off-road excursions. Our test mule was able to crawl up and over extreme rock obstacles with only a few tread lugs grabbing. This particular JK has tested some other giant radial tires as well, and the owner tells us that nothing has pulled like these in the rocks. |
 Highway We've never run across...  Highway
We've never run across a "perfect" tire before, so we weren't all that disappointed to find out that the MT/R with Kevlar did have a downfall-the highway ride is decent, but it does do some tracking on uneven pavement and does make some road noise. Also, the fact that this tire has a very pliable sidewall combined with the 42-inch diameter on a 17-inch wheel lets the tire do a little dancing on the wheels.
For the vast majority of consumers looking for 42-inch tires, the average highway performance of this tire will be of little concern when compared to the off-road prowess of the new Kevlar MT/Rs. |  Overall Impressions To say...  Overall Impressions
To say that we enjoyed testing with this tire would be an understatement. Not only did the Goodyear 42-inch MT/Rs surpass our expectations in the dirt, but also on rocks too. The tire did an amazing job of sticking to obstacles and pulling itself up onto things that other tires would just sit and spin on.
The sidewalls proved to be very flexible, even with the added Kevlar, and throughout all the testing, we never put serious damage into any of them.
The highway ride was not the best we've ever had, but the tire is still more than suitable for driving on every day and we were more than happy to sacrifice a little on-road performance for the awesome off-road performance. | |