Tire size / gear recommendations

User avatar
Jonny09
BSJ 101 Planning Commitee
Posts: 183
Joined: Sun Jan 19, 2020 5:01 pm
Jeep Year: 2009
Jeep Model: JK Wrangler
Real Name: Dale

Tire size / gear recommendations

Unread post by Jonny09 »

OK, so I just installed my 2" lift and I'm now moving on to tires. My plan had been to go from 32 (stock) to 33's while staying on my stock rims. Money is an issue with this build. The main reason I'm replacing my 32's is that they are stock size and tread (Dueler ATs). I need something beefier off road and wanted a little more clearance. The 33's I'm looking at are 275/70r18's and measure out at 33.4. I'm guessing I'll get a true 33 inches installed which is a good 1.5" more than my stock 32's measure out to. Anyway, I'm now rethinking that decision.

My options are:
Stick with 32's, but go more aggresive hybrid or MT.
Go 33's.
or go 35's.

I know EVERYONE would say, no brainer, go 35! but I don't think it is that simple.

32's and 33's will go with my lift without issue.
35's can go with my lift with either flat fenders or bumpstops and shock extensions. (This option means a bit more $ either way.)

My big concern however is gearing. I'm driving an 09 JKU Sahara automatic with 3.73 gears. Lots of folks say 3.8L auto with 3.73 can't handle 35's on the highway or off-road. This chart (https://www.offroadelements.com/ultimat ... 2007-2018/) suggests I can't even go with 33's and that 32's (despite being stock) are pushing what my Jeep can take.

What is your experience? I've only had the jeep since February and been wheeling twice (once with BSJ in the March run). I felt I had no issues that day other than clearance. I kept up with the group and never got stuck. This IS my daily driver and it will spend 90% of it's time (if not 95%) around town and highway driving. But I definitely want to go wheeling as much as possible.

Fact: I cannot re-gear AND get new tires now. Money isn't there.
Are 35's a bad idea without a re-gear?
Are 33's going to be OK without a re-gear?
Should I just get some nice 32's wheel where I can?

I'd ideally like to hear from other 3.8L auto JK owners on what you have found. Thanks to anyone, though, for your thought's and experiences.
User avatar
MDSRACING398
BSJ 101 Planning Commitee
Posts: 3294
Joined: Fri Feb 12, 2016 10:24 pm
Jeep Year: 1985
Jeep Model: CJ7
Real Name: Mark

Re: Tire size / gear recommendations

Unread post by MDSRACING398 »

You will have less issues with 33's or sticking with 32's. Yes you gain 1 or 1.5 inch but that is total so in actuality your only gaining 1/2 to 3/4 in clearance.

35's are heavier so on a used jeep with a budget you are going to go through brakes, possible wheel hubs/bearings etc. The added weight makes things break and also finds issues you didn't know existed. If you are daily driving it, a decent to good all terrain tire would be better than a mud tire. Once again less weight, noise etc. But I am a realist everyone will have a different opinion.
Do it right the first time!
Second place is First Loser! Work Harder
Semper Fi
User avatar
Hoodoo Man
BSJ 101 Planning Commitee
Posts: 3799
Joined: Fri Jan 01, 2010 11:29 am
Jeep Year: 1970
Jeep Model: C101
Real Name: Jeff Cambray
Location: Westford MA

Re: Tire size / gear recommendations

Unread post by Hoodoo Man »

I had an 07 JKU on 35s with a stick and 3.73 and was manageable on the highway and could still pass. I would not consider regearing at all for 33s even with an automatic. I just got a 2010 rubicon automatic and have a set of my old 33" duratacs, its 4.10 but seems fine. I do not plan to regear when I put the 35s onto it.... ( I hope).
1970 Jeepster- stock
2003 Jeep Rubicon 2" BDS Spring lift 35s and MCE fenders
2012 Jeep JKU 2.5' Terafkex spring lift, Rock Hard Bumpa, skids, BodyArmor4x4 sliders..
User avatar
Frank
Frankie BSJ Member
Posts: 4145
Joined: Sun Dec 27, 2009 8:54 am
Jeep Year: 1974
Jeep Model: CJ5

Re: Tire size / gear recommendations

Unread post by Frank »

Jonny :) This can-o worms is deep isnt it ? You looked a a tire ratio chart. Im impressed . Most people just buy now and suffer later. If this is your fist year wheelin with us , Id tell ya to stay with 32/3s and see how she wheels and what she lacks. ATs work good on rocks when it dry , MTs have better grip but do cost you in other ways mentioned . Noise/wear,mileage. If you decide you like doing this with your daily , thats when thing will get expensive. The rest of my opinion dont count for much but Id like to share it with you. As you wheel , look and ask questions of the Jeep drivers that have the same equipment as you. They make something look easy and you have problems. Something they say will help you get better. The one thing you didnt mention in your gear change was some kind of traction device. Yes its added money but your in there anyway. Then theres the 2 door Vs. the 4 door. thats another topic. Do what you can afford to improve your experience out there , Make a game plan and when you ready JustEmptyEvryPocket FjR68
User avatar
pirahnah3
BSJ Member
Posts: 1317
Joined: Mon Jun 27, 2016 9:26 pm
Jeep Year: 1997
Jeep Model: TJ Wrangler
Real Name: Jim

Re: Tire size / gear recommendations

Unread post by pirahnah3 »

Tire size is great but not the end of the wold. Go with what will work all around for your vehicle. In reality you spend much less time offroad than you do onroad with it. The 32s or 33s would be fine off road, ask Dave C how many places he has gone on them. Now granted that is def belly rubbing and having some good skill but it was accomplished. Keep the tires smaller, get some decent AT's you will got most of where you need to just well enough. Spend some money on skids and a winch and in no time you will be able to get around easily. Then as things progress for you, you can put some money away for the upgrades to run 35s including a regear and if you want to lockers.
'97 thats been chopped up and put back together, and ready to take on the trails.
KenCal
BSJ BOD Director at Large
Posts: 506
Joined: Fri Jul 15, 2016 3:35 pm
Jeep Year: 2012
Jeep Model: JK Wrangler
Real Name: Ken Bell

Re: Tire size / gear recommendations

Unread post by KenCal »

Good points everyone. Take a look at General Tire's X3, a cross between AT's and an off road tread. I run these on my F150 and know a club member who runs them on his jeep and says he is happy with them. I run Mud Claws on my JK and like them but you may not on a daily driver, just say'n.
User avatar
BlackKnight
BSJ Member
Posts: 656
Joined: Fri Oct 28, 2016 11:10 am
Jeep Year: 2013
Jeep Model: JK Wrangler
Real Name: Bob, Wife Roxy
Location: Clinton MA

Re: Tire size / gear recommendations

Unread post by BlackKnight »

I'm on 35"s and still running stock gears with an Auto Trans in my JKU Sport with just some computer programming to change shift points and bring the speedo back in line.
--
BlackKnight - Commando Green '13 JKU w/EVO (R Fascia w/D's, ProSeries Front, Skids, 4" Lift) Powerstop z36 kit, 38" Patagonia MTss, PoisonSpyder Diff Armor, SuperWinch w/factor55 Prolink, FOX 2.0 shocks. JKS Track Bars
User avatar
Jonny09
BSJ 101 Planning Commitee
Posts: 183
Joined: Sun Jan 19, 2020 5:01 pm
Jeep Year: 2009
Jeep Model: JK Wrangler
Real Name: Dale

Re: Tire size / gear recommendations

Unread post by Jonny09 »

This is great. Really helpful folks. Thanks.

MDSRACING398 - The added weight is something I was considering, but I've thought more about it since your comment. Even most of the 33's I've been looking at run 60lbs or more. Once you jump to an LT 33 the weight skyrockets. My 32 A/T's (in name only) run about 40lbs. Jumping to 60 seems like a big leap. I was planning on staying away from P series tires but maybe I should reconsider. All the major brands of A/Ts and hybrids sell a number of P-series sizes similar to their LTs. They have a bit less tread depth and obviously not quite as rugged, but they weigh a TON less (43 vs 63 lbs). Is this something I should consider, or because of NE rocks we should stick with LTs?

Hoodoo Man - Yeah, the stick vs auto apparently helps the engine handle the larger tires a bit better. You can manage the RPMs manually. BUT, good to know you ran 35s for a while on 3.73s.

FjR68 - Good words to live by. It is a can of worms and it's sucked me in fully. Jeeps are great because there is always something more to do to them. But that's also a mental and financial (!!) drain. I'm thinking that sticking 32s or 33s is the right choice at this time. If I want 35s later then that's when I'd regear (and consider lockers since I'll be in there anyway).

pirahnah3 - Man, you guys are all so reasonable!

KenCal - Thanks for the suggestion. I looked at Generals as well as a handful of other hybrids (Ridge Grapplers, R/Ts). I love them. But they are running 60-65 lbs a tire. That's a hefty increase over what I'm currently running. This goes back to what I mentioned to MDSRACING398. Many brands sell the hybrids in a P series and LT. Is P worth considering (for weight) or will I rip the sidewalls to shreds?

BlackKnight - Good here first hand accounts of what I'm thinking. I know of others with 2012+ running 35's with the stock gears and have good luck. But the 3.6L is apparently much more powerful that my 3.8. I never would have thought the 3.6 would be that much stronger that the prior model, but that's what I'm reading. Don't know enough yet, myself.
User avatar
RandyCarol
BSJ Member
Posts: 1134
Joined: Sun Jan 31, 2016 10:58 am
Jeep Year: 2013
Jeep Model: JK Wrangler
Real Name: Randy
Location: Dracut, Ma

Re: Tire size / gear recommendations

Unread post by RandyCarol »

Not worth replacing tires if only going up an inch unless you need new ones anyways or you go aggressive. In my opinion. Get some skid plates and use a little more skinny pedal. ;)
Stubby antenna & Prorock 60’s
User avatar
BlackKnight
BSJ Member
Posts: 656
Joined: Fri Oct 28, 2016 11:10 am
Jeep Year: 2013
Jeep Model: JK Wrangler
Real Name: Bob, Wife Roxy
Location: Clinton MA

Re: Tire size / gear recommendations

Unread post by BlackKnight »

Any tires/rims you're looking at are going to be HEAVY compared to your current. It's the nature of the beast...

That said, I'm running stock gearing with 35" Generals AT2's and they are heavy bastards...
--
BlackKnight - Commando Green '13 JKU w/EVO (R Fascia w/D's, ProSeries Front, Skids, 4" Lift) Powerstop z36 kit, 38" Patagonia MTss, PoisonSpyder Diff Armor, SuperWinch w/factor55 Prolink, FOX 2.0 shocks. JKS Track Bars
User avatar
Frank
Frankie BSJ Member
Posts: 4145
Joined: Sun Dec 27, 2009 8:54 am
Jeep Year: 1974
Jeep Model: CJ5

Re: Tire size / gear recommendations

Unread post by Frank »

So you know . The 3.6 is only 100 horse power more than the 3.8 . Its really how they programed it that makes the 3.6 feel like a power house compare to the 3.8. Im pretty sure , if your buying new tires to go off road , Id recommend a 3ply side wall . You will thank me later. If your not gonna drag race to work , dont worry about how heavy they are. Once up to speed you only have to keep them rolling. As I said , look at builds of 4 doors and see what people protected first and what they changed second. FjR68
KenCal
BSJ BOD Director at Large
Posts: 506
Joined: Fri Jul 15, 2016 3:35 pm
Jeep Year: 2012
Jeep Model: JK Wrangler
Real Name: Ken Bell

Re: Tire size / gear recommendations

Unread post by KenCal »

The makeup of AT's and off road tires is the reason they weigh more. Generally the AT's and off road tires have more plies, 3 ply side walls and thicker treads and more in some cases. Wheeling can and is rough on your tires, sharp rocks and even large sticks can slice a tire. This is one of the reasons for requiring you to have a full size spare when we wheel. A good tire and wheel might weigh 100 lbs. or more and that's just the nature of things, don't obsess about it. Nothing is going to be more helpful to you than experience or as you often hear someone say seat time, that's when things will start to make sense. And no matter the tire size with the proper gears you'll never notice the difference of larger tire's, in fact your jeep will drive like it did when you first got it.
User avatar
Jonny09
BSJ 101 Planning Commitee
Posts: 183
Joined: Sun Jan 19, 2020 5:01 pm
Jeep Year: 2009
Jeep Model: JK Wrangler
Real Name: Dale

Re: Tire size / gear recommendations

Unread post by Jonny09 »

Again, really helpful folks.
So I guess that my planned setup of about 85-88lbs shouldn't bother me too much. I am planning on reprogramming the computer for larger tires so hopefully that will mitigate some of the "under-powered" complaints I keep hearing about as well as address the shifting patterns.
User avatar
RandyCarol
BSJ Member
Posts: 1134
Joined: Sun Jan 31, 2016 10:58 am
Jeep Year: 2013
Jeep Model: JK Wrangler
Real Name: Randy
Location: Dracut, Ma

Re: Tire size / gear recommendations

Unread post by RandyCarol »

88 lbs isn’t bad. My wheel/tire combo is about 130 lbs
Stubby antenna & Prorock 60’s
User avatar
MDSRACING398
BSJ 101 Planning Commitee
Posts: 3294
Joined: Fri Feb 12, 2016 10:24 pm
Jeep Year: 1985
Jeep Model: CJ7
Real Name: Mark

Re: Tire size / gear recommendations

Unread post by MDSRACING398 »

You guys are light weights lol
Do it right the first time!
Second place is First Loser! Work Harder
Semper Fi
Post Reply