Does Rubicon even use 8th gear??

[jeepoch]

Is there a digital read out where you can see what gear you are in? If so, how do you program the dash to display it?

Randy,
As others just posted, there is a configuration setup via the 'Electronic Vehicle Information Center' (EVIC) in the center of the instrument cluster. According to the JL owners manual pg. 202:

"Screen Setup
Push and release the up or down arrow button until the
Screen Setup Menu Icon/Title is highlighted in the instrument
cluster display. Push and release the OK button to
enter the sub-menus and follow the prompts on the screen
as needed. The Screen Setup feature allows you to change
what information is displayed in the instrument cluster as
well as the location that information is displayed."

Look for the configuration item named 'Current Gear' and change it from 'Off' to 'On'.

Current Gear
• On
• Off (default setting)

Then when in Drive the gear # will be shown as D1-8. When in Autostick, just 1-8 is displayed.

I find that being able to watch the transmission shift is very useful information. Because of it, I use the Autostick feature way more often, especially at highway speeds, in order to either up or downshift into or out of 8th gear.

For reference, I drive a lifted 2019 Sport S on 35s with the stock 3.45 differentials. So 8th is not selected as often as it used to on the stock 31.5" tires. My eighth gear is essentially now "Overdrive on Steroids" with these bigger tires. I typically get about 3 to 4 more mpg when I use 8th more aggressively.

However give credit to this pretty amazing ZF8 transmission. Since I manually shift into 8th quite often, the trans seems to have noticed and it shifts into 8th much more frequently than it ever used to. It's nice to notice it's in 8th already whenever I go to upshift. Still it doesn't select the top gears like it did purely stock but with a visual indicator I can control this transmission now just like a manual but without the clutching calisthenics.

The current gear presentation is really cool. You can watch just how smooth the shift points are, particularly in the middle range. It's remarkable to see when the shifts occur, especially when they are not mechanically discernable.

Off-road, I find that I'm generally always in Autostick (manual mode). I find that explicit control of the gears is way better, especially in 4lo. Many Jeepers would never even consider an automatic transmission just for that very reason. With this 'Current Gear' setup configured, this ZF8 is a better manual trans than the manual transmission itself. You can now pick up and control things manually (or not) based on whether you believe you can do better than the trans controller. For me, this makes Jeeping way (way) more fun. Man vs Machine sort of thing.

It amazes me that this display configuration is not 'On' by default.

Jay

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[CarbonSteel]

I created a thread some time ago where I said that all Rubicons (specifically 3.6L gas engine models) should come geared from the factory with 4.56 and was flamed for it with the usual statements of “must be a new Jeep owner” blah, blah, blah. I said this due to my experience with mine in headwinds and in the mountains. The simple fact is the 3.6L is gutless below 2K and so it is on the line with 33” tires in 8th gear.

Now that I have upgraded to 35” tires, it is even more obvious that 4.10 gears are not good enough—8th gear is non-existent above 70ish, a slight headwind or hill will have you in 6th in the blink of an eye, and the constant down and up shifting is not good for the transmission from a long-term point of view. I will be re-gearing to 4.88 soon and while there are some who may say that 4.88 is aggressive for 35” tires, it will put me where I should have been with 33” tires and 4.56 gears.

Granted, I understand that FCA has a balance to maintain between drivability and fuel economy, etc. but 4.56 would not be over the top for a Rubicon—especially those with heavier 33” tires. At the very least, FCA should take a nod from Ford and offer multiple gear ratios as an option and let the buyer decide. As with everything, YMMV!

 

[WontonJLUR]

I'll see 8th a few times on my 26 mile commute with cruise set at 62. Stock 4.10 gears and 39" tires

 

[Ruby Mike]

I just upgraded to 35 inch tires. I am using stock 3.73 gears with the diesel and so far no problems. I go up interstate 8 mostly in 8th gear with it shifting to 7 only on the steepest grade. Sunrise highway has always been 6th gear and that didn't change. The diesel doesn't even notice the bigger tires.

 

[Petey]

I have a 2020 Rubicon Recon, only 2500 km so far. I notice that it is a pretty rare occasion to see the Jeep shift in to 8th gear. I know the tires are slightly larger on the Rubicon but it also has 4.10 gears. I thought that it would shift in to 8th sooner than something that isn't geared as low. At 110 km/h (68 m/h) it is almost always in 7th gear. Is this normal?

just wondering what are the RPMs @68 and 7th? And then, if it goes to 8th, @what speed @RPMs? Is it on a totally flat road with no incline?

 

[Petey]

On the 6 speed manual, I rarely get past 4th gear. 6th is unusable.

I use 6th all the time (highway of course) about 2000rpms , maybe a bit less, @about 70mph . happy it is there ...squeeze out about 26 mpgs of flat road with the gear otherwise it would go down by about 3 mpgs in 5th maybe even 4mpgs

 

[Thunderjet]

Checked mine today when I was going 55 on a level road. 8th gear at 1500 rpms.

 

[txj2go]

I created a thread some time ago where I said that all Rubicons (specifically 3.6L gas engine models) should come geared from the factory with 4.56

What about those of us with 33" tires and 3.45 gears? I find this marginal- flat ground, low altitude, little wind, it will run 8th gear at our speed limits which vary 70 to 75. Higher altitude, a little headwind, a little uphill and it stays in 7th. I just go back from a 2000 mile trip to Utah through Colorado and this was the typical behavior. I always thought 4.10 in the Rubicon was overkill and my experience goes along with this. With the original 31.5" tires the car stayed in 8th most of the time. So 31.5" tires and 3.45 gearing going to 33" tires the gearing should go to 3.70 max. Of course unless you are going for high speed, lower gears will always improve responsiveness (and hurt mileage). I realize there's more to it than just rpms- the increased tire width and mass has to be compensated for too.
I'm going to try the autostick to hold it in 8th more and see how that goes.

 

[CarbonSteel]

What about those of us with 33" tires and 3.45 gears? I find this marginal- flat ground, low altitude, little wind, it will run 8th gear at our speed limits which vary 70 to 75. Higher altitude, a little headwind, a little uphill and it stays in 7th. I just go back from a 2000 mile trip to Utah through Colorado and this was the typical behavior. I always thought 4.10 in the Rubicon was overkill and my experience goes along with this. With the original 31.5" tires the car stayed in 8th most of the time. So 31.5" tires and 3.45 gearing going to 33" tires the gearing should go to 3.70 max. Of course unless you are going for high speed, lower gears will always improve responsiveness (and hurt mileage). I realize there's more to it than just rpms- the increased tire width and mass has to be compensated for too.
I'm going to try the autostick to hold it in 8th more and see how that goes.

Autostick did not/does not hold mine in 8th and if my 3.6L is lugging with 35" tires and 4.10, a 3.6L with 3.45 and 33" tires has to be as well. As with all things, expectations are different for each person, but I also think those who say "it is just fine" need to share their definition of "just fine" (not saying this is you) and know they are simply "living with it".

For me, "just fine" is the Jeep not doing the things I describe, but if putting it into drive and having it go is that definition, then yeah, it is just fine. If the definition is the engine should not be lugging, it should reasonably hold 8th gear (certainly 7th gear), MPG should not take such a hit, the performance should not be sluggish, and the transmission should not be frequently shifting up and down. I chose tires that were only 4 pounds heavier than the OEM 33", yet my performance and MPG took a hit and I can definitely tell that it has. Perhaps, I am more sensitive to it than others, but for me, I am not going to live with it and try to say that it is "just fine".

 

[zrickety]

I use 6th all the time (highway of course) about 2000rpms , maybe a bit less, @about 70mph . happy it is there ...squeeze out about 26 mpgs of flat road with the gear otherwise it would go down by about 3 mpgs in 5th maybe even 4mpgs

You have the sport? Tires and gear ratios are different. I tried 6th and 5th actually delivers better MPG on the highway, for the Rubicon.

 

[Arterius2]

I see 8th on my Sahara with 3.45 gearing and 35s sometimes. Pretty sure your big bad Rubicon should too.

 

[Petey]

You have the sport? Tires and gear ratios are different. I tried 6th and 5th actually delivers better MPG on the highway, for the Rubicon.

Yes they are however + slightly taller Sahara rim tire combo., yet I still get better in sixth without a doubt. (flat road of course) ......U have a taller gear ratio in the diff so u should benefit more from the overdrive. Is ur wrangler weighed down with a bunch of accessories?

 

[zrickety]

Yes they are however + slightly taller Sahara rim tire combo., yet I still get better in sixth without a doubt. (flat road of course) ......U have a taller gear ratio in the diff so u should benefit more from the overdrive. Is ur wrangler weighed down with a bunch of accessories?

No, it's a bone stock 2 door. I hear what you're saying, but it's really lugging the engine in 6th unless I'm breaking the speed limit at 80. 5th gear I get the same mileage and the engine is happier. Around town, 4th is best, even going 55.

 

[Petey]

You have the sport? Tires and gear ratios are different. I tried 6th and 5th actually delivers better MPG on the highway, for the Rubicon.

Just noticed u have 2door ur running a bit lighter than I thought . How strange that 6th doesn't give u better mpgs.

 

[Petey]

No, it's a bone stock 2 door. I hear what you're saying, but it's really lugging the engine in 6th unless I'm breaking the speed limit at 80. 5th gear I get the same mileage and the engine is happier. Around town, 4th is best, even going 55.

I'm in 6th by 60mph I skip 5th once I get enough speed from 4th on the highway....it doesn't ping and use it for holding speed not for accelerating. It doesn't feel like lugging and automatics are at that range also.

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