Best plan for 35" tires with minimal loss of daily driver usability?

JIMBOX

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Good info and my HANKOOK DYNAPRO MT-LT315/75RX16-are listed at 35:+++, but

When installed on 16x8" alloy wheels and psi of 30lbs--they are 34"

There ain't no reason forit--it's just the way we doit !

W.E.

JIMBO
The stock Rubicon tires are 32.2" mounted on the Jeep. The 285/75-17 KO2 is 33" exactly. And the 35x12.50 is 33.5". All of these I measured using a level and tape measure while the tires were on the Jeep.

BFGs run small, but most brands are smaller than their listed sizes due to a difference in how we measure tires vs. how manufacturers measure tires. When we measure, we do a straight line and we use various wheels of various widths at various pressures. The tire makers use a specific wheel and take into account the bulge of the sidewall.
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mwilk012

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Stock tires, 285/70R17, are 32.7", while 315/70R17 are 34.4". That's almost a 2" difference. Where's the false information?
The falsity is in reality.
 

Beartooth

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That sounds like a really high pressure to run them at. I think most are running them in the 28-32 PSI range.
The load index and max load both decreased when I swapped tires, so revised OE psi should increase as vehicle weight is unchanged. I don’t have an actual BFG load index inflation table, but there is a formula for calculating the revised OE tire pressure.

Subtract the new tire max load from the OE tire max load: 2755lbs - 2535lbs = 220lbs.
Calculate the new tire max load lbs / max tire psi: 2535lbs / 45psi = 56.3 lbs/psi
Find the psi adjustment for the tire swap: 220lbs / 56.3 lbs/psi = 3.9 psi

OE door sticker pressure is 37 psi: 37 psi + 3.9 psi = 40.9 psi

JLUR weighs 4390 lbs or roughly 2195lbs per axle, so we can confirm the revised pressure in a generic C load index inflation table. If you were to graph the table below for OE load index 116, you would find OE 37 psi is at 2195 lbs. The 113 load index needs a higher psi for the same 2195 lbs.

Aside from the math, you have to inspect the installed tires. The tire shop inflated them to 41 psi, but I lowered them to 39 psi due to the 7.5” stock rims changing the tire shape. They handle and ride well at 39, but 37 or 38 would probably be fine too. Winter is coming and there is a 1 psi change per 10 F. I could lower to 30 psi, increase the rolling resistance 10%+, lower the mpg, decrease handling and have the 8 speed auto gearing hunting at 75 mph.

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WLFMOON

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I'm running cooper stt pros 35" with a teraflex puck kit-Didn't need it because I have a rubi, but I thought it looked better. Drives and rides fine. That setup would be the best for daily driver and no loss of drive-a-bility....
 
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ormandj

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I'm running cooper stt pros 35" with a teraflex puck kit-Didn't need it because I have a rubi, but I thought it looked better. Drives and rides fine. That setup would be the best for daily driver and no loss of drive-a-bility....
How are the 35" STT pros as a daily driver tire compared to the stock KO2s? Any problem with reverse sensors? Would love to see some pics of your setup.
 

jlsahara

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On my Sport S, even with the 2.5" lift and wheels with a -12 offset, my 35x12.50x18 tires rub the rear fenders at full flex.
I have the same setup and I love the daily driving on it. Sometimes I wish I would’ve gotten 17’s and then I remind myself that I don’t want to ruined my current daily driving usability.
 

Earlscott

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The tires look great. How's the highway noise vs. the KO2s? Ride? Seems like they stick out quite a bit on those wheels. Does it set off your parking sensors?
Slighty louder road noise than KO2's, not bothersome though. Yes they stick out more, a couple inches. Does not bother parking sensors.
 

ChattVol

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I have the same setup and I love the daily driving on it. Sometimes I wish I would’ve gotten 17’s and then I remind myself that I don’t want to ruined my current daily driving usability.
I wanted to ask you and @TheRealTVGuy...did you try running 315/70/17 ko2's on your jlus with stock wheels and 2.5" lift? I'm curious how bad they would rub?

Secondly, I daily drive and wknd warrior my jlus 6 speed with added rubi takeoff suspension/wheels/tires to my jlus 6 speed and got a 1.75' lift and the ko2 285/70/17 tires havent rubbed offroad. Gas mileage and gearing has obviously been affected.(2-3mpg loss and barely use 6th gear on hwy) How is your 3.45 gearing handling 35" tires? I would definitely feel the need to regear to 4.10 or 4.56 going to 35" tires as I only have pull in 6th gear with 33" rubi tires when going 75mph on flat or downhill highways.

Do you offroad at all? I've read alot about folks cautioning sport owners with d30 axles and adding 35's to be careful offroad bc of pushing the strength limits of the axles. I'm actually talking with a dealer now about taking a $10k hit and trading for a rubi to get wider/stronger d44 axles, lockers and 4.10 gearing all under warranty. :cwl: Very tough pill to swallow and prob wont do it. If not, I'll wait for more locker options to come out and regear to 4.10 at that time. I really wish I went with the rubi with lockers originally or atleast d44 limited slip rear.:headbang: After getting stuffed on few climbs and watching lockers in action, they are an absolute gamechanger offroad.:rock::flag::jk:
 
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TheRealTVGuy

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I wanted to ask you and @TheRealTVGuy...did you try running 315/70/17 ko2's on your jlus with stock wheels and 2.5" lift? I'm curious how bad they would rub?
:rock::flag::jk:
I didn’t. I went straight from the stock setup (which at 6:20am I’m having trouble remembering, lol) to the 18” Fuel/35” Nitto combo.
 

ChattVol

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I didn’t. I went straight from the stock setup (which at 6:20am I’m having trouble remembering, lol) to the 18” Fuel/35” Nitto combo.
I gotcha...do you know the optimal wheel backspacing to allow flex for the 315/70/17 on the jlus with 2.5" lift for folks who like the tire tucked under the fender as much as possible? I'm not crazy about wheel spacers. Thanks
 

ChadTx

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I have 315 70-17 BF Goodrich Ko2’s On my Rubicon with no problems at all. I first had the stock wheels then I switched to fuel Anza wheels and still no problems. I have a winch on the steel bumper group and I did notice that my front end dropped about 1/2 inch after adding the winch. I may put a spacer up onto the front To get back that 1/2 inch and other than that I’m not even sure the Rubicon needs a lift. At least not for my purposes, if I decide later on that it does the most I would do would be to add a Teraflex one and a half inch leveling kit to it.
Do u have a picture??
 

SRP

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Anyone running 285/75R18 Falken Wildpeak AT3W on a stock JLUR? I’m considering a +20 offset wheel (Fuel Ammo) to keep them tucked under as much as possible. Weekend trails not rock crawlin.

The offset calculator says they’ll fit, 1” more backspace, 1” farther out, and 1” less room under the fenders than stock (2” taller overall).

Thanks in advance
 

Drey06

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I'll just share some of my experience with hope it helps you out. I'm running a Sport S with a 2.5" lift from Rock Krawler on 18" Fuel wheels and Nitto Terra Grapler G2 35x12.50X18 tires. I Like the width of my tires and because of the -12 offset of the wheels, they stick out past the fender which I feel help me with CG issues, especially on banked curves. The Nittos, while not inexpensive, are a great quality tire with low noise.

I Love my setup and it works well for the wheeling I do, but because of the weight of the lift components and the weight of each tire/wheel my MPG's went down by about 5. This may be too beefy a setup for what you plan to do. I'll close by adding that the biggest issue that affected driving/handling performance was TIRE PRESSURE! Both my stock tires and my installed Nittos came aired-up to over 40 psi. The Jeep was weaving all over the place. After I dropping it to 36 psi, it drives fantastic. So whatever you decide to go with, CHECK & ADJUST YOUR TIRE PRESSURE!
Did you have any issues with 8th gear? Did you need to regear your sport? Debating 33s bc minimalistic but love 35s look. Dont plan on kuch off reading more so wanting a slight clearance increase. Daily driver vehicle.
 

WranglerMan

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My 2018 has a RC 2.5” boost and run 35” KO2’s and it’s a daily driver, after doing the boost and wheels along with bumper and winch my mileage dropped down to 18-19 on the highway but hey it’s a brick on wheels, I don’t see 8th gear that much and considered regearing but after talking to my resident expert Chris of Tank Customs here in Houston @TTEChris advised me to save my $$$ on the regear as I would never recoup the investment and so far my JL runs great
 
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