First Off Roading with 37" BFG Tires on Stock Jeep Wrangler JKU Suspension

  / autoedits_jason  
Here's the video of my first Off Roading in the 2013 Jeep Wrangler Unlimited with the 37" BF Goodrich KM2 tires stuffed under the stock suspension!
If you are curious as to what it took to make the tires fit on the Jeep. I mounted them up on the stock Rubicon rims so that saved a bit of money for now but the backspace on those rims needed to be moved out for a bit more steering clearance so I bought a set of 1.5" G2 wheel spacers and bolted those on first. The front tires then fit up pretty good, only rubbing on the rear of the frame rail at full lock but were extremely close to the stock fender lip. It looked awesome but as I drove around town, they rubbed quite a bit. So, I yanked the front fenders off in anticipation for the Metalcloak Overline Fenders I will be putting on this rig.
To fit the rear tires, things got a little more involved. I had to remove the stock rocker guards (I will trim those and put them back on soon) and make a slight cut to the leading edge of the wheel well. I have seen videos of people just hammering this area in for clearance but cutting it seemed a better option for me. The tires then fit fine but the fenders came off in the process and I just left them off for now since I have the Metalcloak stuff on order. Plus the Jeep looks kind of cool with no fenders. It's not legal in California but I'll enjoy it until the new stuff gets here.
After that, I went ahead and got the gear ratios changed by swapping the ring and pinion to a 4.88:1 kit from G2. Since the axles shafts had to come out to do the gear change, I figured I would just kill the credit card and buy upgraded chromoly axles shafts at this point as well... I'm glad I did. Then I used my Diablo Sport inTune unit and re-calibrated the speedometer and put the 87 octane tune on the PCM. That alone made a noticeable difference in the throttle response and makes the Jeep "feel" sportier to drive.
Then I went out and hit the trails! I headed to an easy trail near me called Drinkwater Trail that winds above the old St. Francis Dam up San Fransisquito canyon. If you get few minutes look up the story about that, it's kind of wild.
Not having the proper bump stops kept me from really hammering on the Jeep and the tires did rub a bit but everything survived pretty great (minimal damage). The performance of the tires on the windy canyon road to the trail was amazing! I absolutely love the way they feel on the road, very confidence inspiring in the twisty stuff and they go great down the highway as well. The KM2's are actually less loud than the stock mud terrains that came on the Jeep.
Off road, these tires and this Jeep are like cheating. This combo makes anyone (even a newb like me) feel like an accomplished off roader. There was so little drama getting up the steep sandy stuff and the fast fire road blasts felt amazing! Now if I can just get the stability management nannies to shut off for that 2wd stuff it would be perfect.
So next up should be fenders and bump stops to make the rig less likely to destroy itself on a big hit and be legal on the road.
Stay tuned and please subscribe to the channel and share these videos to help me keep making more!

Best,
Jason