We are new Jeep JK Unlimited owners and I am looking for help deciding what size tires to go with. We purchased a 2010 Jeep JK Unlimited Sport ( Automatic ) with the 3.8 engine. We will be using for every day commute and standard adventure to include gravel roads, camping trips, and trips to the lake. I will be installing a 2 inch spacer lift and some new shocks. I have stock 18 in wheels and 2 in wheel spacers that I have not decided if I will install or not. My big question is the tire size. I would like go have a slightly more aggressive look and stance than stock, but I do not want this thing to be a dog on the highway and I will be running stock gears. Will the 2 inch wheel spacers cause me problems, or decrease performance? What would be a good tire size for my application and use. Thanks in advance.
Trying to make decision on tire size for my 2010 Jeep Wrangler Unlimited
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First you need to know what gears you have, going to a tall tire may cause you to have to regear. Enter your VIN number in this link and you can find out.
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I wouldn’t recommend anything over 33” diameter with either factory gear setup. Stepped up to 35s from 33s with the factory 3.73s and it’s a whipped dog on highway hills pulling a trailer.
I’ll be improving to 4:56s in a couple months to restore performance.
Skip the spacers. They’re a hazard to your health and well being. Buy new wheels if different backspacing is needed.
I’ll be improving to 4:56s in a couple months to restore performance.
Skip the spacers. They’re a hazard to your health and well being. Buy new wheels if different backspacing is needed.
I have 35s on my JKU with a 2.5" lift and 3.73 gears and it gets up and down the road just fine. I don't tow anything with it and I do moderate trails, beach runs and logging trails with no issues.
I considered going to a 4.10 or 4.56 at one time when I thought about a trailer, but that never happened.
I considered going to a 4.10 or 4.56 at one time when I thought about a trailer, but that never happened.
I'm running 33" BFG K02 right now .
Measures out to 32" ish.
3.73 Gears and its good on the
trails and HWY,
Plans are to switch. to a 35" after
lift . So will regear at that time.
I've got a 3.8 as well so considering
4.56 like @SmowbirdTom.
Question , why do you have
2" spacers? As @SnowbridTom
was bang on with his assesment
of spacers . Ideally you want wheels
with 4.5" of backspacing . It will give
clearnce for 1 ton tie rod/drag link ends.
As it will push the wheel out 1 1/2" compared
to stock. It will also add additional clearance
for larger tires and after market control arms
if you ever decide to mod any further .
So to answer your question . 33" or 35"s
depending on current setup and how much
you want to spend .
Measures out to 32" ish.
3.73 Gears and its good on the
trails and HWY,
Plans are to switch. to a 35" after
lift . So will regear at that time.
I've got a 3.8 as well so considering
4.56 like @SmowbirdTom.
Question , why do you have
2" spacers? As @SnowbridTom
was bang on with his assesment
of spacers . Ideally you want wheels
with 4.5" of backspacing . It will give
clearnce for 1 ton tie rod/drag link ends.
As it will push the wheel out 1 1/2" compared
to stock. It will also add additional clearance
for larger tires and after market control arms
if you ever decide to mod any further .
So to answer your question . 33" or 35"s
depending on current setup and how much
you want to spend .
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Unfortunately, the vendors who sell you the spacers are not likely going to let you know it may be difficult to find someone willing to do alignments and keep your front end straight as long as spacers are installed.
You can go up to a 35" tire with your 2" lift. You will probably have some rubbing under flex, but that can be fixed with a little judicious trimming.
35" tires on a non-Rubicon will be a dog, though.
You may find these useful.
Do not install wheel spacers. They're terrible. They lead to premature wear and failure of suspension components, up to and including your wheel coming totally off. Get wheels with the proper backspacing and offset. It will cost you more up front, but will save you money in the long term.
I am non-spacer guy too. I know there are different types, some a lot better than others. For me it is just one less than to worry / think about. I think for most people 35” tires will do 95% of what people want to do when off-roading. Plus beyond 35” cost goes up in order to do it right.
Agreed. There's no hard and fast rule, but I think it's pretty reasonable to say that beyond 33" (for the D30 in non-Rubicons) or 35" (for the Rubicon D44) you need to be thinking about an axle swap. Or costly repairs. Because one or the other is almost certainly in your future.
There are exceptions, of course. I had 40" tires on a D44 in a V8 YJ. But it had manual hubs, which allowed me to put hub fuses in both sides. Those are cheap, easy to change, and blow well before the more expensive bits.
I have 35's on my jk Nad it was a dog with factory gears. I went up to 4.56 gears and changed the differential to a limited slip. I don't off road enough to justify the cost of lockers.
Ive got an 09 Rubi. I run 35s no problem. Can do 75 no problem. Make sure you tell the jeep it has new tire size.
Also make sure your drive shafts are correct for lofr and 2" tire size increase. I get about 13.5 mpg around town and 15 t0 16 on highway depending on how heavy my foot is. On a long trip speed is negated by need for fuel, urine etc.
Also make sure your drive shafts are correct for lofr and 2" tire size increase. I get about 13.5 mpg around town and 15 t0 16 on highway depending on how heavy my foot is. On a long trip speed is negated by need for fuel, urine etc.
Only if you’re really unlucky. At least the 3:73 carrier can be upgraded with better gearing.
I have a 2015 sport, the build sheet said 3.73 but when I lifted the rear tires and actually checked the ratio learned the I had 3.21's. I upgraded to 4.46 with limited slip differentials.
Which limited slip did you go with ? How do like ?
I ask cause that is the direction I’m leaning .
Eaton Trutrac for the rear and Spartan LSD for the front .
Originally was planning an Eaton ELocker for the rear but the price has sky rocketed to $1800 CDN for just the locker!
I went with the Yukon Limited Slip differentials. I like them but I was warned that I could cause the front to pull just a little to the right. It does but it's barely noticeable.
I've been eyeballing the Yukon stuff with install at a local offroad shop. They seem to have a decent rep. Good to hear they're working for ya.
Started the "Regear to Add Torque" fund at my CU. Kinda like a Christmas Club account with real life meaning.
Just one contributor - me.Sorry for the delay. I have confirmed that I have 373 gears. I have heard that the 3.8 lacks some power as it is. I have some factory 18's and some LT 275/70 R-18 which I think calculates out to a 33 in tire. I thought about those, maybe some wheel spacers and a 2 inch puck lift. However, if that is going to make this thing a complete dog, I will just stay factory tire size and maybe do the puck lift and then add the spacers. Thanks
I will skip the spacers then and maybe save up for some aftermarket wheels. So when you were running the 33's you seemed to get up and down highway just fine then.