I'm very fond of the look, and overall size (not wanting to lift, and only wanting to level the front) of the 265/75 R16 tire on the JK. Have been researching nonstop and pretty much came to the conclusion that anything over a 32" tire on 3.21s doesn't add up to a decent driving rig with the exception of losing a gear, or 2, on highway and uphill runs.

So, running a 265/75 R16 tire will put me at a width of 10.43" and an overall diameter of 31.64". Practically, a 31.50x10.50 tire, roughly.

Will that constitute to the MPG dropping greatly and/or having a difficult time driving on 6th gear on the highway? How about offroadability? Read many people needed 4LO, more than usual, but of course on a 32"+ tire.

Other members with 3.21s and a 265 tire, please chime in.

Thank you.

 

this is what i run and have no problems other than 6th being useless until i'm about 65+ mph -- it feels fine in the lower gears and all i have is a CAI and exhaust -- i can smoke both tires through first and on the trail its fine ---- its mainly the hills that i need to be in 5th or pulling my lowboy with two 4WD four-wheelers on it -- but the difference 6th makes is really nothing - i feel that i have good power and i have no idea about gas mileage never checked it -- i think the slow pokes is the auto, lots of people complaining about that especially with bigger tires of any kind -- so, thats what i run and i like it, i also have the 2"BB but you don't need that to fit those tires

 

i agree 6th gear is useless. im runnin stock sahara wheels and tires- 255-70r18 i believe and it runs perfectly fine. i also have 3.21's.

 

I have 3.21 and 285/75/16's and have no complaints other than 6th below 65 or on hills....then I just shift down to 5th.

On the trail...no problems on moderate trails..(greens and blues)...I would not want to try anything harder with them.

I do have the 2dr which also helps

 

I've been running the 265 75 16 for a couple of weeks now with a 6 speed 3.21 unlimited, and love it. I use 5th more, and feel like i probably should have been doing so all along. I will not go so far as to say that 6th is useless... just speed up, then ride in 6th all day.

I don't think there was a real noticable difference in power or pickup, though i know there was some. I don't think my mileage was affected at all.

 

I have been running this setup for about 7 months now with no problem whatsoever. I even took a trip (about 3500 miles) with it. Hills, mountains, straight highway, no issues. 6th gear is good above 65.

MPG on the highway ran about 17mpg. In and around town about 15.

I have also done moderate to difficult off roading with these tires and have gone everywhere a Rubicon has gone without issue . I don't plan on going any bigger, out of fear of losing power and performance.

Hope this helps.

 

Going from 5th to 6th gear drops 400 rpm off the tach....hardly a huge difference.



A lot of people also forget that if the tires are bigger, the engine is doing the same work for the same speed, even if 6th is "useless"....as 2 grand at 60 mph = 2 grand at 60 mph....

....It really doesn't MATTER if its 2 grand in 5th, or 2 grand in 6th, if you're stilll going 60 mph in either situation......

So - its more like going to bigger diameter tires is just like installing a deeper overdrive.

 

Sweet, guess I'm going with this size. Thanks for all the input guys, appreciate it.

 

I too have the 265/75R16 with the 3.21 gears (2-door).....I don't understand the claim that 6th is "useless", I use it all the time...even down around 45-50 mph on level ground. Now, if you're climbing a hill then yeah I gotta downshift to 5th, or 4th if it's a big one. The only real complaint that I have is when you're on a trail and wanna go up a hill in 2wd or climb over a small rock or whatever, there's not much "ooomph" to get it done....so sometimes I just stay in 4LO so I won't burn the clutch up.