To those with the new Xtreme recon package

[Steph1]

Wondering if those of you that had a JLU Rubicon on 35s and traded for one with the extreme Recon package saw a mpg difference between a Rubi with 4.10 and one with 4.56 ???

Reason for asking is that I am planning on regearing my 2018 Sahara with the 3.6 and am hesitating on which gear ratio to go with.

No I didnt buy a Jeep for fuel economy, but I hate spending more than I have to on fuel.

thanks

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[aldo98229]

My Sahara will be getting 4.88s in ten days. I should be able to tell you then.

 

[falcon241073]

Guess I’ll be watching this thread since I plan on a regear in may.

 

[Steph1]

My Sahara will be getting 4.88s in ten days. I should be able to tell you then.

4.88s holly geez, what size tires do you plan on running?

 

[Rubi SoHo]

I drove a 3.6rubi on 33’s when shopping for mine. The XR is quicker, and I’m getting 17mpg in mostly city driving.

 

[falcon241073]

4.88s holly geez, what size tires do you plan on running?

I’m going with 4.88 gears. But I’m running heavy 37” tires and beadlocks. I contemplated 5.13 gears but I think that’s be a little much on the highway at 70+ mph.

 

[DadJokes]

If you’re gonna miss it, miss it low…from personal experience with a few other gear swaps. If you’re on the fence between two, go with the numerically lower gear ratio.

 

[aldo98229]

4.88s holly geez, what size tires do you plan on running?

I’ve been running 35x12.5 General ATs for about a year now. They are true 35s, not quasi-35s that measure 34.4 or 34.5.

My MPG is absolute crap: I get 13 in the city and 15 on the freeway. You can feel the Jeep struggling to maintain 70 MPH with the factory 3.45 gearing. The transmission rarely goes above 6th speed any more; it will stay on 5th gear if there’s a headwind.

I checked with five shops; they all recommended 4.88 gears. Their reasoning is that the Jeep not only has to handle 35 inch tires, which would require at least 4.56 gears, but it also has to contend with the additional drag generated by the wider tires and the taller frontal wind resistance from the lift. There’s no difference in cost.

This is she right now

 

[Steph1]

If you’re gonna miss it, miss it low…from personal experience with a few other gear swaps. If you’re on the fence between two, go with the numerically lower gear ratio.

That’s exactly what the gear guy said as I was planning on 4.10s and he said to then go with 4.56. Hence why I’m asking the question to you guys that know

 

[Steph1]

I’ve been running 35x12.5 General ATs for about a year now. They are true 35s, not quasi-35s that measure 34.4 or 34.5.

My MPG is absolute crap: I get 13 in the city and 15 on the freeway. You can feel the Jeep struggling to maintain 70 MPH with the factory 3.45 gearing. The transmission rarely goes above 6th speed any more; it will stay on 5th gear if there’s a headwind.

I checked with five shops; they all recommended I got 4.88 gears. Their reasoning is that the Jeep not only has to handle 35 inch tires, which would require 4.56 gearing, but it also has to contend with the additional drag generated by the wider tires and, the taller frontal wind resistance from the lift. There’s no difference in cost.

This is she right now

Makes total sense. I must say that my 315 K02s registered as 34s by Jscan are well managed by the 3.45s thanks to a Hikeit X9 throttle controller. Most people would totally live with it, but I too like to make modifications, but they should enhance the driving experience. Not the opposite.

 

[aldo98229]

Keep in mind Jeep is including 4.56 on the XR package with 315 tires, which are 34.4 inches. When given the choice, automakers will give you a taller gearing to help their EPA numbers.

Apparently, Jeep is now offering 4.88 as a factory option.

 

[aldo98229]

Makes total sense. I must say that my 315 K02s registered as 34s by Jscan are well managed by the 3.45s thanks to a Hikeit X9 throttle controller. Most people would totally live with it, but I too like to make modifications, but they should enhance the driving experience. Not the opposite.

I too could live with the 3.45 gears. But the Jeep just doesn’t feel right, especially on the freeway.

Around town I can barely notice any difference.

You don’t have a lift? That’d would help with the stock gears on the freeway.

 

[DadJokes]

That’s exactly what the gear guy said as I was planning on 4.10s and he said to then go with 4.56. Hence why I’m asking the question to you guys that know

I was meaning if you’re trying to regain your rpms and get them back up to normal (or close to it) again after going with larger diameter tires and you’re between 4.56 and 4.88’s, go with 4.56’s. Now the step between 4.10 and 4.56 is bit wider spread but if I was hesitant with the higher than desired rpms I’ve calculated for what tire I’m running…then run the numerically lower of the two.

 

[Steph1]

I too could live with the 3.45 gears. But the Jeep just doesn’t feel right, especially on the freeway.

Around town I can barely notice any difference.

You don’t have a lift? That’d would help with the stock gears on the freeway.

I have Rubi suspension and 3/4 inch coil spacers. Looks just right to me with the 315s. Cant go any higher since my indoor garage at work has a very low clearance. 76 inches‍.

 

[FreedomFur]

I am getting about 14mpg with a new JLUR w. XR and 37s. Not great, but maybe lost 1-2mpg switching to the 37s. Also have a steel front bumper, winch, etc. It’s only gonna get worse once I add the skids underneath and rear bumper. Guessing it will settle around 13mpg. That could be driven down lower than others since I get off road at least once a week and don’t reset the gas stats, and 4H/4L sucks down gas.

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