Just regeared to 4.88 in my 2021 JLUR 2.0T

[falcon241073]

Had the axles regeared last week to 4.88. Running a 3.5” lift and heavy 37” tires. Picked the Jeep up yesterday and reset the liar dash MPG monitor. It is usually close to hand calculated MPGs. I’ve been getting 14-15mph moxed city/hwy driving. The current readings after the reset has been 16.5-17.5 mpg. But I haven’t been hard on the pedal because it’s new gears lol. I’m pleasantly surprised and hope it stays around this.

Just thought I’d share. But it’s not going to be an accurate assessment until I run a couple tanks of fuel thru and hand calculate the MPGs.


Yes my Jeep has been recalibrated for the tires and the gear sizes. And no I didn’t regear for the MPGs. And yes I hold 8th gear a lot better than before.

And so far I’m happy I went with 4.88 over 5.13 gears. I think 5.13 would be to deep for a daily and long trips across the country. At least with 37” tires. Just my opinion.

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[jlrubeinswaz]

Had the axles regeared last week to 4.88. Running a 3.5” lift and heavy 37” tires. Picked the Jeep up yesterday and reset the liar dash MPG monitor. It is usually close to hand calculated MPGs. I’ve been getting 14-15mph moxed city/hwy driving. The current readings after the reset has been 16.5-17.5 mpg. But I haven’t been hard on the pedal because it’s new gears lol. I’m pleasantly surprised and hope it stays around this.

Just thought I’d share. But it’s not going to be an accurate assessment until I run a couple tanks of fuel thru and hand calculate the MPGs.


Yes my Jeep has been recalibrated for the tires and the gear sizes. And no I didn’t regear for the MPGs. And yes I hold 8th gear a lot better than before.

And so far I’m happy I went with 4.88 over 5.13 gears. I think 5.13 would be to deep for a daily and long trips across the country. At least with 37” tires. Just my opinion.

I too went with 4.88. Running 37" BFG KO2s. 3.6 and with all the aftermarket stuff and interior goodies I am up to 5750 lbs. I know the BFGs are a light tire. I got a chuckle about the MPG monitor. Glad I am not the only one. As far as mileage it depends on the highway speeds for me. 60-65 I can see 18 mpg. 70 to 75 its 15 mpg.

 

[falcon241073]

I too went with 4.88. Running 37" BFG KO2s. 3.6 and with all the aftermarket stuff and interior goodies I am up to 5750 lbs. I know the BFGs are a light tire. I got a chuckle about the MPG monitor. Glad I am not the only one. As far as mileage it depends on the highway speeds for me. 60-65 I can see 18 mpg. 70 to 75 its 15 mpg.

Lol. I see the 3.6 and 2.0 run about the same then. Those are about the same numbers I’m seeing so far. And god forbid I hit a head wind. Lol.

Oh well. It’s better than it was. And it’ll be better Offroad. And I didn’t mind the way it handled Offroad with the 4.10. So the 4.88 should be awesome. I’ll find out in a couple weeks. Got to drain and inspect the gears. Put on my new diff covers and head to the trails. Lol.

 

[JeepViking13]

Just curious how the Jeep dealerships treat the warranty aspect of this MOD if something goes wrong? Only asking because it seems a lot of Standard Rubicon owners change gears from 4.10s to 4.56 and 4.88s or higher to run bigger tires.

If something goes wrong with the rest of the drive train do they try and blame the aftermarket gears?

Im curious also because I decided to go the Willys Xtreme Recon route and I already have 4.56 gears and other upgrades from the factory but might eventually be looking to add a Locker. So I'll be in the same boat but for a different reason. Same area though. Same idea.

Just wondering how far down the rabbit hole the dealers try and go out of their way to blame stuff like that even though it might not really be the cause of like a transmission problem or anything else that goes wrong in the drive train??

 

[jlrubeinswaz]

Just curious how the Jeep dealerships treat the warranty aspect of this MOD if something goes wrong? Only asking because it seems a lot of Standard Rubicon owners change gears from 4.10s to 4.56 and 4.88s or higher to run bigger tires.

If something goes wrong with the rest of the drive train do they try and blame the aftermarket gears?

Im curious also because I decided to go the Willys Xtreme Recon route and I already have 4.56 gears and other upgrades from the factory but might eventually be looking to add a Locker. So I'll be in the same boat but for a different reason. Same area though. Same idea.

Just wondering how far down the rabbit hole the dealers try and go out of their way to blame stuff like that even though it might not really be the cause of like a transmission problem or anything else that goes wrong in the drive train??

I am sure they will try to deny anything they can. It's kinda a double edge sword. My view is you want to go bigger tires there is a lot that goes with it. If something goes wrong or breaks I will upgrade to something that will last or stand up to the environment. I don't want to replace with what broke. With me I am only looking for other stuff to be warranted like electrical and AC kinda stuff. That is all can hope for.

 

[JeepViking13]

I am sure they will try to deny anything they can. It's kinda a double edge sword. My view is you want to go bigger tires there is a lot that goes with it. If something goes wrong or breaks I will upgrade to something that will last or stand up to the environment. I don't want to replace with what broke. With me I am only looking for other stuff to be warranted like electrical and AC kinda stuff. That is all can hope for.

Yeah it definitely is. I would just worry about big things like the transmission and stuff. They deny that it won't be cheap. Just curious if anyone has gone through that debacle over gears or lockers?

 

[falcon241073]

Depends on the dealer. But once I regeared the internals of the axles lost the warranty. Easy to blame the regear labor or the parts on the locker messing up if it ever does. I’ll just drop an Eaton or arb in it’s place if that happens. I have RCV axle shafts on order. So no worries about the stock axles breaking. But if those where to break or splines twist then Stellantis could blame the 37” tires anyways. So regear wouldn’t matter any ways.

My service writer told me unless it’s $2000-$3000 minimum he is rarely questioned on warranty coverage. So they basically take his word on whether to covers a claim or not. Main reason is my dealer hasn’t been caught trying to cheat or over charge warranty claims. That’s what usually gets them watched closely. My dealer is also very mod friendly. (At least as much as they can be per warranty policies) and they regularly sell and work on modified trucks and Jeeps. The owner even has heavily modified Jeeps. Most dealers who don’t work on modified Jeeps and deny coverage don’t want to mess with them. It can be more difficult or complicated versus a stock vehicle. Adding time to remove aftermarket parts or work around stuff. The mechanics complain because it takes them more time. Time they aren’t paid for.

 

[falcon241073]

Yeah it definitely is. I would just worry about big things like the transmission and stuff. They deny that it won't be cheap. Just curious if anyone has gone through that debacle over gears or lockers?

Main reason to work on a good relationship with a good dealer. Ask question to the service writer, or better yet the service manager. Just bluntly ask their policy on modified Jeeps. How they handle warranty claims, etc. if they claim to have no issues and say they help then ask for examples of big claims where the Jeep was modified. If they do what they claim then they won’t have an issue telling you about things they’ve seen and got covered. If they balk at answering then find another dealer to do work in the future or be prepared to pay out of pocket.

 

[JeepViking13]

Depends on the dealer. But once I regeared the internals of the axles lost the warranty. Easy to blame the regear labor or the parts on the locker messing up if it ever does. I’ll just drop an Eaton or arb in it’s place if that happens. I have RCV axle shafts on order. So no worries about the stock axles breaking. But if those where to break or splines twist then Stellantis could blame the 37” tires anyways. So regear wouldn’t matter any ways.

My service writer told me unless it’s $2000-$3000 minimum he is rarely questioned on warranty coverage. So they basically take his word on whether to covers a claim or not. Main reason is my dealer hasn’t been caught trying to cheat or over charge warranty claims. That’s what usually gets them watched closely. My dealer is also very mod friendly. (At least as much as they can be per warranty policies) and they regularly sell and work on modified trucks and Jeeps. The owner even has heavily modified Jeeps. Most dealers who don’t work on modified Jeeps and deny coverage don’t want to mess with them. It can be more difficult or complicated versus a stock vehicle. Adding time to remove aftermarket parts or work around stuff. The mechanics complain because it takes them more time. Time they aren’t paid for.

Sounds like the best solution is to find and take the Jeep into a MOD friendly dealership for warranty work or just work in general.

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