The Lowest Lift and 38’s On A Jeep Wrangler Rubicon
Installing larger-than-stock tires on the Jeep Wrangler is a great way to increase off-road performance and ground clearance. For 2018 and newer Rubicon models, shoehorning on massive rubber is particularly easy thanks in part to the highline fenders and extremely large wheelwell openings. On four-door models, moving up tire sizes is especially beneficial to compensate for the 118-inch wheelbase.
While we’ve shown you in the past how well 2.5 inches of lift and 37’s performs under our 2021 Jeep Wrangler Rubicon 392, we wanted to push this low-lift big tire configuration even further. To do so, we grabbed a set of one of the most popular and true-to-size 38’s on the market, the 38x13.50R17 Nitto Trail Grappler. In this article, we’ll detail what it took to run this tire under our Jeep with only 2.5 inches of lift, along with pointing out the major pros and cons of doing so.
Trail Grapplers
Given Nitto tires run more true-to-size than most, and the 13.50-inch tread width being more common for the 38, the 38x13.50R17 Nitto Trail Grappler is the ideal candidate for this test. We say test mostly because we pulled this tire and wheel package off of our Jeep Gladiator Rubicon to essentially test if this would work before deciding if 38’s would be the right next tire for our Wrangler.
Our Method(s)
One variable that is extremely important to consider is our wheel specifications. Our 38’s are mounted on a 17x8.5 Method 701 Bead Grip wheel. This wheel has 4.75 inches of backspacing, which provides a great balance of tire poke and component clearance.
Rig Specs
Our 2021 Jeep Wrangler Rubicon 392 is equipped with a 2.5-inch suspension system from JKS Manufacturing. One thing we’ve learned over the years is that suspension heights can vary wildly from one manufacturer to another. For this reason, we’ll focus on what matters more, which are the bumpstops that come with the kit.
Front Stops
For our setup, we found that a total of 3 inches of bumpstop spacing is all that is needed to clear the 38’s up front. On the 392, the bumpstop perch is actually two inches longer than all other Wranglers. That means we only had to add a total of 1-inch of additional bumpstop spacing at the front axle. If you have a standard Rubicon, you will need a 3-inch bumpstop at the axle.
Rear Stops
Out back, the chassis side of the bumpstop perch is the same as all other JL Rubicons. We wanted to retain the most amount of uptravel. So, we used 2.5 inches of bumpstop spacers and trimmed the few areas that it did contact. Going with more bumpstop spacing will reduce the amount of trimming but will cut into the travel of the Jeep. This means reducing the ride quality and performance of suspension, which is mostly noticeable off-road.
Trimming
Two areas that needed to be addressed were at the backside of the rear fender flares. The first one is an easy rubbing fix as all you will need to do is unbolt the small plastic liner that keeps debris out of the rear bumper. The second thing we had to do was trim a small section of plastic at the base of the rear part of the inner fender. Using a razor knife, we removed a little over two inches of plastic that was contacting at full articulation.
Bumper Caps
It’s also worth noting that we removed the bumper end caps that come standard on the Rubicon steel bumper group. This provided the extra clearance necessary to clear the tires. For those running a plastic front bumper, you will rub slightly on the back side of the bumper. Not enough to do any significant damage, but you will hear it make contact off-road. A stubby front bumper is highly recommended.
Spare Tire
Our 2021 Wrangler Rubicon did have the Xtreme Recon package, which meant we had the reinforced tailgate and tire carrier relocation mount. While we managed to install our spare tire in the stock location, it did rub on the back bumper slightly. This works OK for daily driving, but we’d recommend a better aftermarket tire-carrier solution if you plan on more serious off-highway adventures.
Trail Pressure
These wheels are part of Method’s Bead Grip line, which means they have patented internal grooves securing both the inner and outer bead of the tire. This means you can safely drop the tire pressure much farther off-road with this setup versus a conventional wheel. We found 12 PSI to be a great balance of traction and ride quality.
Trail Performance
We have years of experience with the Nitto Trail Grappler. So, we knew just how well this tire performs in the dirt. Having it in a 38x13.50 creates a tremendous amount of grip, even in wet and muddy trail conditions. The tires clean out easily, even at low speed, creating a very consistent and reliable feel on the trail.
Heavy Steering
Compared to a 37x12.50, the 38x13.50 had a more notable impact on our steering. At trail pressure, it was challenging to navigate in the rocks. This was only compounded when the front locker was engaged. If you are planning to make the move to a 38, we highly recommend investing into a steering upgrade. A hydraulic-assist steering kit from PSC Motorsports would be our personal first choice.
Practical Setup
Compared to a 37’s, the 38’s on the street didn’t make nearly as much of a difference as we thought. Yes. You could tell there was a slight power hit. However, with the 38-inch Trail Grapplers being only 3 pounds heavier than the 37x12.50R17 Nitto Trail Grapplers we were running previously, it wasn’t enough where we would say that one is better or worse.
Watch It In Action
If you want to learn more about this setup and watch it in action, be sure to click HERE. This link will take you to our full video review of this setup and an in-depth look at how it performs.
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