I have a 2010 jk 2d auto with 3.73 gears. I am currently running 255 75r17 wrangler mtr Kevlar. I am looking to upgrade to a larger tire, 33 - 34. I am looking at the nitto terra grappler 305 70r17. Wondering if anyone has any experience running that size tire with 3.73 or any input. I'm not planning on regearing for some time so I'd want it to be liveable with the 3.73s. I have a teraflex 2.5 coil lift with shocks to be installed, just want to figure out the tires before I install the lift. I'm not trying to make the same mistake I made last year when I bought the 32 inch mtrs and hated the size a week later. any input or advice would be greatly appreciated. thanks all.

 

My situation is a little different, but just to throw this out there - I've got a 2012 JKU with 3.21 gears running 33x12.50r15 Duratracs. Although I'm currently installing a Teraflex 1.5" coil leveling kit, I am able to run the Duratracs with no issue on my setup. One thing to mention is that my wheels are Level 8 Trackers with 3.75" BS. I know that I'm running the 3.6 and you have the 3.8, but there's absolutely no discernible performance loss with the bigger/wider tires.

 

Don't waste money on a 34", get the 35's.

I don't have experience with the size you are looking at, but ran the 295/75/16's for a while. Spec'd at 33.27", ride height was right at 32" under vehicle weight. (I think yours are spec'd closer to 34", so you might expect them to measure out to 33", or a bit less, under vehicle weight?)

One thing you can do is search for the actual ride height for that tire, then plug the number into the chart in the faq's. Once you get the rpm, divide it by .69. That will give you the OD Off rpm, which you can use for a comparison to your current rpms.



An example - more useful for people trying to decide on which gears to go to, but it may help...

auto, 3.73, 31" actual height (stock 32" tires)
1953 rpm @ 70

auto, 3.73, 34" actual height
1781 rpm @ 70 (OD On)
/ .69
2581 rpm @ 70 (OD Off)

auto, 5.38, 34"
2569 rpm @ 70 (OD On)


So, in this example, you would lose 172 rpm @ 70 by moving up to the taller tires. And then pressing the OD Off button would give a fair comparison to 5.38 gears.

 

Without a re gear I would stay where you are at. When you are ready to re gear go 34-35's and some 5.13 gears.

 

I've got an 08 4spd auto on 35's with 3.21

Leave the OD off unless on flat roads or downhill and don't expect it to launch quick, but it's easily livable. I will be regearing eventually, but until then, I have no regrets.

Get 35's and enjoy the look

 

I run an 08 6spd with 35s on a 4.25" RC lift, it was a bit much at first but I chipped it along with intake, exhaust and throttle body spacer and it does great. I'm a daily driver w it , now I still drop it back down to 3rd if I need to get up hill w some pace or pass someone. Re-gear is a bit pricy so in the meantime I'm content.

 

315/70/R17 Goodyear Duratracs. I highly recommend these tires. They run a little small so they are perfectly on the 34 range. I cannot say enough great things about these tires.

 

Ran 33x12.5 on a 2010 auto JKU with 4.10s and it was ok but hwy driving was frustrating at times; did this for about 18 months. Decided to run 35x12.5 on the same setup and I hated it. I lasted 2 months before I decided to go with 5.13s. The regear was the best money I've spent on the jeep. I would strongly suggest a regear if you want to run larger tires.

 

33x12.5x15 Duratracs measure out at around 31.5 inches so no difference from stock really. Each wheel and tire combo weighed less than stock as well, with alloys.

 

If the duratracs don't run as high, do the run less wide also?