This wasn't in the brochure...

[Save The Manuals!]

"Southern Iowa Hills" = still flat, for those of us who live Rockies and West.

Try downshifting. Stella gave you 6 gears for a reason. If an automatic would grab a lower gear, you should too.

Or you can re-gear your axles and run 2500-3000 rpm in the 70mph range and have a little better crawl ratio off-road.

I'll be making the same trip again in a couple weeks. I'll experiment with downshifting and see how it does. Any chance my mpg will improve???

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[Save The Manuals!]

392 is your answer...

or cummins swap

Well, I did just pay off my house...I guess I could sell it and live in a 392...

I'm sure the Cummins swap wouldn't be cheap either. We had to do a long block rebuild (whatever that means, I just repeat what I hear) on our 2003 Ram 2500 in 2017, I think. I could pop the hood and show you what $15k looks like.

 

[Save The Manuals!]

It’s a Jeep, not a Hellcat dear….

Your gearing is matched to your engine’s torque which is matched to its emissions rating which is matched to the octane it burns which is matched to its ethanol fuel rating and Iowa is certainly known to sell ethanol.

Actually, I managed to find 87 octane non-ethanol in Iowa--I know, that's sacrilege there. Best I can do here is 91 non-ethanol unless I have a reason to drive it to Arkansas where I've bought 87 real stuff for my motorcycles.

 

[Ratbert]

I have been driving stick shifts for decades.: 1974 VW SuperBeetle, 1974 Jeep CJ5, 1974 Fiat Spider, 1980 Fiat Spider, 1984 Chrysler Laser, 1987 Dodge Daytona, 1992 Mercury Capri, 2006 PT Cruiser, 2003 Ram 2500, 2013 VW Bug TDI, and 2006 Ram 3500. And motorcycles for 16 years (and instructed for 15 years). The only trouble I ever remember having was driving the Capri over the Rockies. I fully understand the concept of matching gears to speed. But this is my first experience with a vehicle needing downshifted on Midwestern hills. Clearly, something is different than what I'm used to, so there is a learning curve required on my part; thus, I am seeking advice of those experienced with JL MTs. I wish to learn what to expect.

You have to realize that 6th is nearly useless in these things, especially if your diff gears aren't numerically high enough. For me (at high elevation in Colorado) my Rubicon's 4.10 gears were nowhere near enough with the 3.6. Those were the numerically highest gears available from Jeep at the time.

 

[AVGeek99]

Gears may be the answer in your case but my 21 JLU Rubicon with 37s has never had that problem, even in the real mountains. I see other people telling others to re gear when you move up in tire size all the time and in a lot of cases it's very unnecessary.

I have to assume you have the automatic, which does handle bigger tires more gracefully, but with 37s you'd still benefit from a regear.

With the 6MT on the other hand, a regear is mandatory with 37s if you ever want to see 5th or 6th gear, even in a Rubicon. But the OP has a sport with 3.45 gears, making it that much worse.

User experience with larger tires with the automatic does not at all translate to a similar experience with the 6MT.

 

[AVGeek99]

Sorry, but the 6 speed manual in these things is geared horribly tall.

TRUTH!!

But when look at the gearing charts 8th for sure and maybe 7th in the auto are even taller than 6th in the MT. But the auto makes up for this in how smoothly it downshifts. The only way you know it downshifts is by monitoring RPMs. And it is noticeable once you get to 3k RPMs. The auto is also programmed extremely well to always shift at the right time.

 

[Save The Manuals!]

TRUTH!!

But when look at the gearing charts 8th for sure and maybe 7th in the auto are even taller than 6th in the MT. But the auto makes up for this in how smoothly it downshifts. The only way you know it downshifts is by monitoring RPMs. And it is noticeable once you get to 3k RPMs. The auto is also programmed extremely well to always shift at the right time.

I've driven automatics while working for the dealership. They are incredibly smooth, and that's probably why I've never noticed how often they do or don't downshift. But I haven't driven any autos on much of a hill...I don't think. Or maybe I just didn't notice.

Not only do I love manuals, but that auto would've cost me another $4500. I can learn how to do a better job of shifting optimally for that much. I really appreciate everyone's coaching!

 

[Save The Manuals!]

Funny thing about all this: For some reason I'm reminded of The Bad News Bears. As my JL struggled up those hills (such as they are), I envisioned Engelberg, the catcher , struggling to run laps with the other kids. And he, like my JL, is always eating. I dunno, I may have stumbled upon a name for him...

 

[Zandcwhite]

I have to assume you have the automatic, which does handle bigger tires more gracefully, but with 37s you'd still benefit from a regear.

With the 6MT on the other hand, a regear is mandatory with 37s if you ever want to see 5th or 6th gear, even in a Rubicon. But the OP has a sport with 3.45 gears, making it that much worse.

User experience with larger tires with the automatic does not at all translate to a similar experience with the 6MT.

I disagree that the manual needs a regear anymore than an auto. The driver just need to downshift as early and as often as the auto does. Above 2nd gear the torque converter is locked up so the power throughout most of your daily driving is applied just the same through either transmission. Just because the manual owner doesn't want to shift properly doesn't mean they need to regear, it's user error. If they wanted a Jeep that once they were on the highway they never had to shift...they wanted an automatic. As far as "never seeing 5th and 6th", that's like the auto owners who "never see 8th", how the hell do you guys drive up hill everywhere you go? I see 8th all the time both with 4.10s and 37s and 4.56s and 39s. Obviously not up hill or into a headwind, but under low loads as intended in a double overdrive transmission.

 

[Twisted10]

Well, I did just pay off my house...I guess I could sell it and live in a 392...

I'm sure the Cummins swap wouldn't be cheap either. We had to do a long block rebuild (whatever that means, I just repeat what I hear) on our 2003 Ram 2500 in 2017, I think. I could pop the hood and show you what $15k looks like.

i have a 22 cummins. nothing cheap about it but when tuned its some of the sweetest noise made

 

[73TAWM]

I have to assume you have the automatic, which does handle bigger tires more gracefully, but with 37s you'd still benefit from a regear.

With the 6MT on the other hand, a regear is mandatory with 37s if you ever want to see 5th or 6th gear, even in a Rubicon. But the OP has a sport with 3.45 gears, making it that much worse.

User experience with larger tires with the automatic does not at all translate to a similar experience with the 6MT.

Yea I have a 2.0 and almost didn't comment because of it but I see this so much with all of them that my comment was for the guys not knowing and yes I should have lead with what I had, to clarify for those people.
The amount of difference I would see by re gearing isn't worth the cost to do it. I have had other guys, mainly JK guys, drive it and tell me I had no reason to re gear and one of them actually does the re gear in Jeeps all the time. It's my first Jeep and so naturally when I see these comments I'm thinking I need a re gear. But after I did the lift and still had the 33s on it, it handled like shit and was very top heavy feeling. After moving up to 37s and adjusting the Taser Mini to reflect the tire upgrade it went back to feeling like stock off the parking lot. When I travel the mountains with other JKs, who have been re geared, I have to slow down so they can keep up to the point it's annoying.

I only made the comment because some guys on here and facebook jeep groups will be insistent on a re gear when it's not always necessary, it seems to be a knee jerk reaction.

 

[Valpo Jeep]

Our JL has the ZF auto and it hunts gears terribly going down the road between grades and wind. Our Maserati has the ZF and will hunt gears on grades but its geared and programmed for its power. Our old Audi A7 had the ZF as well but it hardly hunted gears.

Despite all 3 having a ZF trans (different versions and computer programming) all 3 would react a bit differently.

Back in college I had gutless manual 4 cylinders and having to row the cars up hills was the norm. After college my V8 manual Mustangs had the power to make me row the car much less.

Like said earlier, an auto will still hunt gears and you may not even notice it but with a manual you will almost always have to downshift to maintain speed. Letting it lug the engine down is not the best idea as you might lug it down too much where you compromise that oil film on a bearing.

 

[Ratbert]

Our JL has the ZF auto and it hunts gears terribly going down the road between grades and wind.

It's unusual to hear complaints about the automatic. Stock gears and tires?

 

[Zandcwhite]

It's unusual to hear complaints about the automatic. Stock gears and tires?

People don't understand that a double overdrive transmission, especially paired with an engine that makes peak power well past 5k rpms, is going to shift a lot. That's not hunting gears, it's functioning as designed. The load on the engine and thus shifting is more affected in a brick on wheels than a Maserati or audi by the wind? Shocking. His profile Pic looks too be a stock non-rubicon. With 3.45 gears it won't hold 8th under any kind of load be that a headwind or slight hill. That's a 2.31 final drive ratio. Not that forums existed back then, but I wonder if people discussed running 2-1 axle gears and why they had to downshift a lot before overdrive was a thing?

 

[autotragic]

I have been driving stick shifts for decades.: 1974 VW SuperBeetle, 1974 Jeep CJ5, 1974 Fiat Spider, 1980 Fiat Spider, 1984 Chrysler Laser, 1987 Dodge Daytona, 1992 Mercury Capri, 2006 PT Cruiser, 2003 Ram 2500, 2013 VW Bug TDI, and 2006 Ram 3500. And motorcycles for 16 years (and instructed for 15 years). The only trouble I ever remember having was driving the Capri over the Rockies. I fully understand the concept of matching gears to speed. But this is my first experience with a vehicle needing downshifted on Midwestern hills. Clearly, something is different than what I'm used to, so there is a learning curve required on my part; thus, I am seeking advice of those experienced with JL MTs. I wish to learn what to expect.

You can expect a lot of down and up shifting on grades. The bigger the tires and higher the gears the worse it is. Down in the hills of TN I just left mine in 5th gear and set the cruise at 70 and it did ok but 6th gear was a non starter unless I wanted to shift a lot. I have 4.10s and 35s which still turn higher rpm than a Sport does with its 3.45 gears and 32 inch tires.

The JL manual trans "feels weird" to a lot of people because it's first gear is super low 5.13:1 for crawling on rocks but is also double overdrive. 5th and 6th gears are both under 1:1. So even in 5th gear you are still in overdrive and 4th is 1:1 or direct drive if you are old school. 2,3,4 are "normal" gears like you expect in any other manual transmission. The combination of super low first and double overdrive 5th/6th makes it hard for people to wrap their head around.

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