Are 35" tires the best for the Gladiator?

[GetnLostnCO]

I upgraded to the 35" Wildpeak A/T 4's on my stock 2020 Rubicon and couldn't be happier. I'll hit 8th gear while on the highway and it gives me amazing off-road capabilities. Highly recommend!

Sponsored

 

[camss69]

Just from an aesthetics standpoint, 35’s with a lift look a little small, I had them without a lift for a couple weeks and they looked great.

With a lift I think 37’s are the sweet spot but you’ll need gears as well to make them livable. That’s why I went 35’s for now. Obviously you gain ground clearance and off road capability with the 37’s as well which is the best part.

In all honestly the 35’s are pretty good off road and I’ve already done some pretty aggressive trails with it. But 37’s are calling me haha!!

35’s no lift and 35’s with 2.5” (really 4”) Gamechanger lift.

 

[ChrisNLA]

Just from an aesthetics standpoint, 35’s with a lift look a little small, I had them without a lift for a couple weeks and they looked great.

With a lift I think 37’s are the sweet spot but you’ll need gears as well to make them livable. That’s why I went 35’s for now. Obviously you gain ground clearance and off road capability with the 37’s as well which is the best part.

In all honestly the 35’s are pretty good off road and I’ve already done some pretty aggressive trails with it. But 37’s are calling me haha!!

35’s no lift and 35’s with 2.5” (really 4”) Gamechanger lift.

Honestly, I find the 35's with the 2.5" lift to be perfect. In real world use it's possible you may be able to get more flex with the 35's than the 37's before stuffing them into the fender.

It's always a trade off. Is the 1" additional ground clearance more useful? Is the potential for more flex while maintaining fender clearance more useful? Etc.

 

[Dilly’S Willy]

If you have a manual like I do and @NortonJTSS do, you'll want a minimum of 4.10s if not 4.56 gears for 35s. If you have an automatic, 4.10s will get you farther, but without a @bmpcamry09 tune you'll see more 6/7 gear than 8th gear.
- People need to get over the whole "I don't see 8th enough" when it's an overdrive gear, so is 7th, they're not power gears. You wouldn't climb a hill in your highest gear in general, you use the mechanical advantage to get up it and shift when you don't need the mechanical advantage anymore.

You bought a truck, not a prius or corolla. Expect below 20mpg average and be happy. Bigger tires = lower mpg/acceleration without regearing at minimum. Tuning is a cheaper alternative for cruising RPMs, but gearing is the key factor when adding weight, regardless of static or rotational.


FYI, my 3.73s with stock 32" MTs on a manual suck ass in the hills or highway, I generally NEVER use 5th/6th gears as they just don't have the mechanical advantage and ruin my avg mpg and cause me to slow down sooner. And I'm still at stock height on my Willys.

 

[RHINO79]

• 35's and 4.10 gears, yes.

• 35's and 3.73 gears, no.

• 33's and 3.73 gears, 8th gear will phone in from time to time.

Very well said!!!

 

[RHINO79]

Just from an aesthetics standpoint, 35’s with a lift look a little small, I had them without a lift for a couple weeks and they looked great.

With a lift I think 37’s are the sweet spot but you’ll need gears as well to make them livable. That’s why I went 35’s for now. Obviously you gain ground clearance and off road capability with the 37’s as well which is the best part.

In all honestly the 35’s are pretty good off road and I’ve already done some pretty aggressive trails with it. But 37’s are calling me haha!!

35’s no lift and 35’s with 2.5” (really 4”) Gamechanger lift.

The 35s with no lift look nice!

 

[Zachanadandy]

I'm guessing 100% of the "not with 3.73 gears" crowd have never run 35s with them? The diffrence between 4.10s and 3.73s is slight at best. The JLU is only a few hundred pounds lighter and comes with 3.45s and 32's. That's nearly identical to running 35s and 3.73s. If you want to know how it will feel, go test drive a JLU sport. You'll still see 8th regularly. The 4.7-1 first gear in the 8 speed is so low it really doesn't matter what you're size combo you run. It will downshift when needed at any speed anyway. Final drive ratio is all the engine sees as far as load. It doesn't know the diffrence between 3.45 gears in 6th, 4.10s in 7th, or 5.13s in 8th as they are mathematically the same final drive ratio. We've run so many different combos between our 2 JLURs and the JT. 4.10s and 33s, 4.10s and 37s, 4.10s and 38s, 4.56s and 35s, 4.56s and 39s, and 5.38s and 38s. The absolute worst was the 5.38s and 38s. It was in 8th gear ALL the time. Like any speed over 40mph. What's the point of an 8 speed when your out of gears by half the legal speed limit? It got 3mpg worse at speed than it did with the stock 4.10s and 38s. Even the factory XR with 35s and 4.56s felt over geared and like you were waiting for it to upshift at freeway speed. The idea that it will pull mountain grades better with lower axle gears is simply false as the auto downshifts as much as it needs to in order to do the work...automatically. Again the engine doesn’t see any difference between 3.73s in 5th gear or 5.13s in 6th. The load is the same and the torque to the wheels is too. These aren't old 3-4 speed transmissions. You have plenty of gearing for all conditions unless you go really extreme either way. 40s and 3.45s would suck. 4.88s and 33s would suck even worse in my experience. Pretty much anywhere in between is more than adequate with this transmission.

 

[bmpcamry09]

Form my experience, from an engine strain and efficiency standpoint, 8th gear is nearly completely useless on every JL and JT, unless your running an extreme setup like 35s and 4.88s or 37s and 5.13s. Any lower number gear ratio, the engine is going to lug in 8th and you may actually burn more fuel than if you stayed in 7th.

The transmission control modules have what is called an aggression counter. Basically the more commanded load the engine has, the aggression counter goes up. When this goes up, the transmission has trouble deciding on trying 8th gear or just sticking with 6th or 7th. That counter has to come back down closer to 0 before it’ll command 8th which requires less load/torque demand. If you have a 150 pound tire and wheel set up, our poor little 3.6 has to command a lot more torque due to rolling resistance.

For this exact reason on many of my tunes I don’t let 8th gear even think about happening until interstate speeds 68-75 MPH. Tuning helps this whole thing by letting the transmission settle into the gear that is best for the conditions, but several of my big tire setups (40s, 42s) with never see 8th gear simply because of the rolling resistance.

 

[Silverator]

JT Rubicon, 4.10s, Clayton 2.5 (really 3-3.5) lift, 35" Toyo Open Country AT3's. Love the look, the drive, and rarely scrape out on the moderate trails. If you're doing difficult to harder trails, why a Gladiator? You're going to have to put a LOT more $$$$ into it to make it perform in those circumstances.

First shot will give you an idea of what 2.5-3.5 with 35's looks like. The second will show you front end clearance (in Sedona here), the third is a rock garden that's no problem with lift and 35's.

 

[Stingray 5517]

Just from an aesthetics standpoint, 35’s with a lift look a little small, I had them without a lift for a couple weeks and they looked great.

With a lift I think 37’s are the sweet spot but you’ll need gears as well to make them livable. That’s why I went 35’s for now. Obviously you gain ground clearance and off road capability with the 37’s as well which is the best part.

In all honestly the 35’s are pretty good off road and I’ve already done some pretty aggressive trails with it. But 37’s are calling me haha!!

35’s no lift and 35’s with 2.5” (really 4”) Gamechanger lift.

Cams69 looking good . What are the details of your lift?

 

[Hootbro]

I'm guessing 100% of the "not with 3.73 gears" crowd have never run 35s with them?

I have and they suck (in my opinion). There is a sliding scale of what each person will put up with with and I would not recommend to anyone that has never driven 35's with 3.73 gears to do it without first driving the setup in another rig as it is an expensive outlay to figure out after the fact.

 

[WambliSka]

Ahhhhhhhhh, we call that home, Subarus and Broncos call that the "end of the trail"

 

[sol90joe]

• 35's and 4.10 gears, yes.

• 35's and 3.73 gears, no.

• 33's and 3.73 gears, 8th gear will phone in from time to time.

A salesman was trying to sell me a jeep with lockers on 37 tires with 4.10 stock gearing. He said several mechanics told him that was fine, nothing wrong with it

 

[ShrimpHappens]

• 33's and 3.73 gears, 8th gear will phone in from time to time.

This isn't true. I've been running Rubicon-size 33's (285/70R17) on my 3.73's for four or five years now. It'll drop into 8th at 52mph running around town, and it'll settle into 8th with the cruise set at 75mph no problem.

A salesman was trying to sell me a jeep with lockers on 37 tires with 4.10 stock gearing. He said several mechanics told him that was fine, nothing wrong with it

Yeah, there's technically nothing wrong with it, because it will function, but the drivability ain't great.

 

[OldMechanik]

I have a 2 inch Mopar lift, true 35 inch tires ( not 34.something) and 3.73s. Definitely looking for 4.88 because I drive in the western Rockies at 4500 feet and more. It’s got enough clearance and flex to do some pretty good wheeling, however it is limited when the rocks get big. Also, yeah, 37s would be nice for the little extra ground clearance insurance. But I might have to install high clearance fenders.
If I were to build another it would definitely be a 40s/5.29/4 inch lift truck

That said, 3.73s aren’t so terrible with 35s. It has acceptable power on the highway and clears any reasonable obstacles.

Note: The Mopar 2 inch lift will not support a 2 piece shell bumper and winch…mine droops about an inch.

Sponsored