4.88 or 4.56 for a 3.6 auto 2022 JLUR?

[NJRadioGuy]

After going to 35s (well, 315/70R/17, so close enough...) I would like to regear. I'd planned to go to 4.56, but two shops who do this kind of thing all day long both suggested 4.88s. I'd say 50% city/suburban, 40% on highways with hills, and 10% off-road on medium-difficulty rocky trails. Thoughts? A few times a year I do 8-hour highway drives, and next year I plan to do a 12,000 mile road trip to northern Canada, so fuel economy and engine noise have to be somewhat reasonable, but I'm tired of it downshifting to 3rd and 4th while accelerating on steep hills at highway speeds. Thoughts?

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[azjl#3]

4.88, cant decide later 454 to small

 

[av8or]

I’d go 4.88. I have 5.13s with 37s and it’s perfect.

 

[Whaler27]

After going to 35s (well, 315/70R/17, so close enough...) I would like to regear. I'd planned to go to 4.56, but two shops who do this kind of thing all day long both suggested 4.88s. I'd say 50% city/suburban, 40% on highways with hills, and 10% off-road on medium-difficulty rocky trails. Thoughts? A few times a year I do 8-hour highway drives, and next year I plan to do a 12,000 mile road trip to northern Canada, so fuel economy and engine noise have to be somewhat reasonable, but I'm tired of it downshifting to 3rd and 4th while accelerating on steep hills at highway speeds. Thoughts?

Maybe some of these will help:

Gearing discussion No. 5482

Gearing discussion No. 428

Gearing discussion No. 3293

Regeariing discussion No. 24,112

Gearing discussion No. 9610

Regearing discussion No. 7283

Gearing discussion No. 274

 

[dragoneggs]

After going to 35s (well, 315/70R/17, so close enough...) I would like to regear. I'd planned to go to 4.56, but two shops who do this kind of thing all day long both suggested 4.88s. I'd say 50% city/suburban, 40% on highways with hills, and 10% off-road on medium-difficulty rocky trails. Thoughts? A few times a year I do 8-hour highway drives, and next year I plan to do a 12,000 mile road trip to northern Canada, so fuel economy and engine noise have to be somewhat reasonable, but I'm tired of it downshifting to 3rd and 4th while accelerating on steep hills at highway speeds. Thoughts?

I’m in a very similar situation as you, except a 2dr JLR. I have 315s w/3.6L auto. 4.10 gears thinking of bumping a bit to 4.56 and many say just go to 4.88. I really want the all around drivability to be good and trying to tweak it to the sweet spot. Not convinced that 4.88 does that with 315s. Sure maybe I would be able to climb a little better but what about highway and in town driving?

 

[Simplejack]

I got 4.56 with my 23 high tide (same tire size as you) all from factory. After 1 yr I'm debating 37s so I would say 4.88 incase u end up in the same boat and wanting to go bigger. However if u do stay with 35s in my opinion the 4.56 is great I put 25k miles in 1 yr on mine with alot of those miles being highway however I have not had 4.88 too compare. I did have 4.10s on rubi gladiator and after upgrading tire size with mopar 2 inch lift I did not like all the down shifting either.

 

[2nd 392]

I’m in a very similar situation as you, except a 2dr JLR. I have 315s w/3.6L auto. 4.10 gears thinking of bumping a bit to 4.56 and many say just go to 4.88. I really want the all around drivability to be good and trying to tweak it to the sweet spot. Not convinced that 4.88 does that with 315s. Sure maybe I would be able to climb a little better but what about highway and in town driving?

Would the about 130 higher rpm w 4.88 vs 4.56 at 65 mph be too much ? Heck, it should be better in town.

 

[kah.mun.rah]

4.88. You will want 37s in the future and 4.88 will work well with the 35s now and ok with the 37s later.

 

[dragoneggs]

Would the about 130 higher rpm w 4.88 vs 4.56 at 65 mph be too much ? Heck, it should be better in town.

Good point… my mpg is going the wrong way with 315s, a 1.5in lift and an aftermarket mid width bumper. Trying not to continue to degrade my mpg as much as possible. I do a fair amount of off-roading/rock crawling but honestly that is only 10% of the miles. I know people exaggerate actual off-road usage when it is their daily driver.

 

[dragoneggs]

4.88. You will want 37s in the future and 4.88 will work well with the 35s now and ok with the 37s later.

So they say… and you are probably right. But I think 35s are the sweet spot for 2drs and much less expensive than 37s. Note that this is coming from a guy that has spent more than $20K in mods, upgrades, and accessories for my 22 JLR.

 

[2nd 392]

Good point… my mpg is going the wrong way with 315s, a 1.5in lift and an aftermarket mid width bumper. Trying not to continue to degrade my mpg as much as possible. I do a fair amount of off-roading/rock crawling but honestly that is only 10% of the miles. I know people exaggerate actual off-road usage when it is their daily driver.

Just get the 4.88’s , yer excuse for 37’s next time is in the bag as @kah.mun.rah suggested yer gonna need tires after yours wear out, geeezz it won’t be much extra then. C’mon

 

[dragoneggs]

So… 4.56 standard on XRs is just a fuel mileage nit?

 

[Bandana]

4.56 if you will never see 37’s. 4.88 if you have even the most remote idea of ever going to 37’s

 

[2nd 392]

So… 4.56 standard on XRs is just a fuel mileage nit?

eh, could be. are not 4.88’s “optional” with 33’s, hmmm ?
Why did my “Rubicon” come with 3.73’s ? Costing me a gears (4.56), 4.10’s could have at least been an option. CAFE perhaps?

 

[Philly_]

Supercharger.

Or I guess 4.88's if I have to choose gears. Having never actually regeared myself, and driving the 2.0T in my JL, take this with a grain of salt, but from everything I've read over the years on this forum, it seems those with the 3.6L consistently gear one set lower than those with the 2.0T. I'm running 4.10's on the same tires and don't mind it at all, but I plan on 4.88's when I make the jump to 37's.

Might not save you on mileage if you really rev it up on the highway, but from what I understand that's the 3.6's happy place anyways.

I also wouldn't bother regearing if you're only going to move one set, but that's just my opinion.

4.88's will feel better if the Jeep is ever super loaded down with cargo, or you add a ton of heavy mods, and will give you some wiggle room to 37's if you ever decide to make the jump. It would be such a bummer to end up bumping up tire sizes later (even if you tell yourself you never will), and want to regear the same axles once again.

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