Off-road enthusiasts often turn to the BF Goodrich KM3 and General Grabber X3 for their excellent performance on tougher terrains, but it’s important to keep in mind, though, that these tires are not so suitable for use on paved roads because of their noise producing structure and a limited gripping capability on roads, especially on wet ones. But still these tires here stand above the crowd. Let me explain why.
In my professional opinion as a tire engineer, the BF Goodrich KM3 provides one of the top-notch experience on sandy terrains with it’s resemblance to paddle tires. The tire basically offers elongated shoulder lugs, and wider lateral grooves, and they are also able to yield quicker mud evacuation and a great climb on rocks. On the other side, the General Grabber X3 offers better on road experience, better wet handling, and superior fuel and tread efficiency.
Tread Structure
General Grabber X3 offers a very biting design of 4 total ribs.
Considering inner two ribs, you see V/U shaped lugs, having full depth notches, and sipes to them.
Their sharp edges make a very tough passing longitudinal groove in the middle, though the outer circumferential channels are slightly wider.
The shoulder lugs are elongated, and have a combination of thin and thick full depth siping.
Like any other traditional tire, they carry wide surrounding gaps with stone ejectors in them.
(I do like the style of these ejectors, you can see “GRABBER” written there).
The shoulder lugs are staggered on the outer edges, and they meet with each other on sidewalls, making sharp biters, along with heat diffusers (which help with towing heat).
On the other side, the BF Goodrich KM3 also comes with a straight forward design.
It has two ribs in the middle, having thick siping slits in between, and outer shoulder ribs, containing two differently shaped “unique” lugs.
These shoulder lugs are staggered and extend down to the sidewalls to produce very thick pattern.
Though towards the middle there isn’t much going on on these shoulders, as they are seen with minimal tread features (only small notches on consecutive lugs.
But they get the job done.
They are actually made to scoop the ground, and throw back the stuff to create forward momentum.
And if you consider how the tire makes wider lateral channels compared to narrower longitudinal grooves, it starts making sense.
Review BFG KM3 here.
Tire Sizes Available
The BF Goodrich KM3 is offered in 56 sizes, ranging from 14 to 22 inches in diameter.
Each size has a speed rating of Q and a load rating of C, D, E, or F, with the heaviest size weighing 83 lbs and the lightest size weighing 37 lbs. (So, in comparison the tire is lighter).
The tread depth on all KM3 sizes is 18/32″, and these tires do not come with a warranty.
On the other side, Grabber X3 offers 15 to 22″ (rim sizes).
They all also have speed ratings of Q.
And Load ratings of C, D and E only are available, which offers this tire with weight range of 50 to 90 lbs.
Tread depth stands between 18 and 21/32″, where majority of the sizes carry 21/32″.
So, this tire features more tread depth in comparison.
Dry Performance
When it comes to analyzing the dry performance of mud-terrain tires, three main dimensions are judged, they include, grip on straight paths, sideways grip, and steering feedback.
three main elements should be considered: traction, steering, and cornering ability. Each of these will be discussed in further detail.
Straight Grip
Overall, mud tires compromise on this type of grip a lot, though with some tires having better structure are able to still provide better efficacy over the others. And that goes for General Grabber X3, as on this tire you get to see shorter stopping distances (a measure of straight grip).
So why is that? Well, because of it’s structure.
It contain two ribs in the middle which are more joined up together, and make 3 longitudinal grooves providing better streamlining with the road.
BFG KM3 on the other hand does things the opposite way around.
Sideways Grip
Sideways grip is seen much better on BF Goodrich KM3. The tire as I explained above does not offer a directionally-streamlined structure, its the opposite.
So if you consider it’s tread again (by scrolling above), you’d note that, it only makes shoulder lugs and the central lugs look like they are divided from these shoulders.
And as these sides come in to action when a tire turns, the KM3 provides a much consistent connection with highways.
Steering Response
Steering response is heavily impacted by the tire’s weight, and here the General Grabber X3 being 10 pounds heavier creates a larger lag between the inputs and the feedback (of the wheels).
The BF Goodrich KM3 on the other is slightly more vocal, as its less susceptible to understeer as much.
Though the difference is marginal, and it’s safe if you keep these tires under 40 mph (and this goes especially for wet traction).
Wet Traction
When it comes to wet traction, you can not expect too much out of mud tires. That’s because although they offer ample hydroplaning resistance, they are not able to give satisfactory grip. I’ve discussed them both one by one.
Wet Grip
Water is not compressible, so in order for a tire to grip, it need to leave out ASAP.
Most of the water gets channeled out with grooves, and the little bit that’s left is dealt with sipes.
So with limited number of sipes, the BF Goodrich KM3 lacks overall, whereas on General Grabber X3, at least you get to have some siping on shoulders, which come in to action on corners.
And wet cornering is the biggest challenge for mud tires.
Hydroplaning
Both tires have no issues when it comes to hydroplaning resistance, as with wider channels the water gets to evacuate out effortlessly.
Though still out of both the BFG KM3 T/A does better on curved aqua tests, where as the Grabber X3 M/T provides better float speeds on straighter paths.
This again has to do with their structure, where BF Goodrich offers better lateral streamlining, and General X3, longitudinal.
Fuel Economy
Rolling resistance, is determined by tire’s weight for the most part. And although the Grabber X3 is heavier in comparison, it’s still gets to consume less fuel.
This has to do with it’s more streamlined designed with longitudinally aligned lugs, allowing it to roll better on highways.
The BFG KM3 in comparison is not as smooth on roads, and it’s full depth lateral sipes, and softer compound waste more energy in to flexing, rather than moving tire as a whole.
Mileage
Out of both tires, the General Grabber X3 provides better mileage (given that you keep some variables constant).
And sure lower rolling resistance is there contributing to it, but it’s stiffer composition (comparatively) and larger tread depth also play a huge role in providing a longer tread life.
The BF Goodrich KM3 on the other side, burns off faster with its softer composition and it’s lower tread depth isn’t helping it as well.
For Your Info: Pro Comp Xtreme MT2 is ranked for providing top notch tread life (compared to other M/T tires).
Snow Capabilty
Both tires are although not 3 peak mountain snowflake rated, that does not mean they would not be able to perform at all on snowy terrains.
In fact these tires are pretty great when it comes to “off-road snow”, or you can say deeper fluffy snow, as their thicker lugs scoop the up and out to create satisfactory forward moving inertia.
Though still out both, the BF Goodrich KM3 is going to be my choice here, as this tire basically yields thicker sipes, which are better optimized for snow.
Furthermore, it’s tread is also much melleable in comparison, and with freezing temperatures, its less susceptible to loose its flexibility.
On the flip end, since the General Grabber X3 lacks these features, its not able to beat KM3 in this section.
Off Road Capability
To navigate on rougher terrains effectively, mud terrain tires need to consider all types of terrains, (and not just mud). Let’s look at all of them one after another.
Rocky Tracks
The General Grabber X3 is a good tire for gripping on rocks, it’s interlocking lugs offers a good efficacy overall, but still you are going to see a better climbing capability on KM3.
BF Goodrich KM3 basically sticks better. It’s although very heavy, it’s stickier and spongier composition molds over the rocky surface with much more friction.
Moreover, it also provides better traction from sidewall lugs, where again it’s softer rubber provides superior flexing abilities and it’s thicker lugs chew with lowered air pressure.
The Grabber X3 although provides a good traction overall as well, it’s harder compound makes it a little hard to control in comparison, though you can achieve similar traction but lowering down the air pressure more (using bead locking rims).
For Your Info: Top performing tire on rocks is Cooper STT Pro.
Soft Sand
On sand you need softer edges, light enough tire’s weight, large enough footprint and “paddles”.
And all of these features are provided by BF Goodrich KM3.
The tire has less sharper sides (compared to other mud-terrain tires), it’s single nylon cap does not allow it to become too heavy, and it’s larger sidewall lugs provide great foot print.
Moreover, you since the tire makes huge elongated shoulder lugs, they act as paddles on sand, throwing it backwards and creating forward momentum.
The General Grabber X3 on the other side, does not create such paddles and is heavier so it tends to dig more, which is the enemy of sand traction.
(I’ve rated BFG KM3 best for sand in the mud terrain category).
Gravel and Dirt
With dual stone ejectors, the BF Goodrich KM3 yields better results off the two, though both tires are very unwelcoming to any stones/dirt to get lodged in their grooves.
This tire basically feature triangular stone ejectors, besides conventional ones (that you see on all tires), and these are placed at the right place in the lateral grooves.
So out of the two tires, you get better results on it compared to Grabber X3, but I do like the fact that this tire is more chip/cut resistant.
Mud Tracks
Being mud-terrain, both tires aren’t going to disappoint you at all here.
Though there are some unique features seen in both tires that you have to keep in mind.
Out of both the BF Goodrich KM3 provides a better mud evacuation with it’s escaping lugs. Since most of the mud demand sideways evacuation, this tire with it’s wider lateral grooves provides exactly that.
But that does not mean this tire would perform better overall.
That’s because the General Grabber X3 creates equal traction with its stronger sidewall lugs and shoulder scoops, as they yield a more powerful forward moving momentum, by throwing mud backwards.
Summarizing
The General Grabber X3 being a heavier and stiffer although lacks slightly in overall steering response, it still offers better tread life, fuel economy, durability, and wet traction.
On the other side, the BFG KM3 provides you with superior wet and snow traction, better overall comfort (bumps absorption), and great mud/dirt evacuation capabilities.
Moreover off road, although both tires are on par in almost all sections, the KM3’s resembles to paddle tires allows it do much better on sandy terrains.
