Mojave should come with 4.56 gears 4.10s dont cut it

[Zachanadandy]

There is a vocal subset of this forum like yours as well.

Your subset claims the other subset is obsessing and not letting the transmission do it's thing.

The other subset never sees 8th gear.

A little embellishing on both sides.

The only way you'd "never see 8th" is if you run 42s and 3.45s... and never go downhill. We've run everything from 4.10s and 33s, 37s, and 38s to 4.56s and 35s, 37s, and 39s to 5.38s and 38s. All saw 8th regularly. 5.38s and 38s was the worst combo. Always in 8th at pretty much any speed over 40mph. What's the point of an 8 speed when you're out of shifts by half the legal speed limit? The best combo was 4.56s and 37s, but even there the difference between that and the 4.10s and 37s in my mojave is so small it would never justify the cost of a regear. One guy on the JL forum even logged 0-60 with 4.10s and 37s and then after the regear to 4.88s... and it's nearly identical. Gears don't add power back. We already have plenty of gearing. If you think 5.13s will be life changing, just downshift. 4.10s in 7th is the same final drive ratio as 5.13s in 8th. If you want more power get a tune (way cheaper than gears for the same small difference) or a supercharger (2x the cost but a real power gain).

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[sunrise089]

The other subset never sees 8th gear.

Never? At what speed?

I drive a tractor sometimes. It has 16 available gear ratios. I never use sixteenth. Should I regear the tractor?

I understand certain combination of tires and use cases benefiting from regearing. But regearing is expensive and introduces a lot of potential complications. I just ask, and have yet to see, what is fundamentally better about 8th gear + 4.56 axle vs 7th gear + 4.10 axle. What is being gained, given the cost, other than a number on the dash?

 

[Wheelin98TJ]

Never? At what speed?

I drive a tractor sometimes. It has 16 available gear ratios. I never use sixteenth. Should I regear the tractor?

I understand certain combination of tires and use cases benefiting from regearing. But regearing is expensive and introduces a lot of potential complications. I just ask, and have yet to see, what is fundamentally better about 8th gear + 4.56 axle vs 7th gear + 4.10 axle. What is being gained, given the cost, other than a number on the dash?

"Never" is the other group embellishing.

In your 8th gear with 4.56 or 7th gear with 4.10 scenario, is the truck with 4.10 shifting often between 7th and 8th?

 

[Zachanadandy]

"Never" is the other group embellishing.

In your 8th gear with 4.56 or 7th gear with 4.10 scenario, is the truck with 4.10 shifting often between 7th and 8th?

What if I told you modern 8 and 10 speed autos are supposed to shift frequently? The latest corvette autos have 4 or 5 overdrive gears. Load goes up, even a little from a hill or a headwind and it's supposed to downshift. The OP is talking about 4.10s and 33s. Yes it will still downshift up a small hill, by design. If your axle gears are so low that it holds 8th under increased loads it is geared too low. It isn't supposed to. It never was. And geared that low you've eliminated the benefit of having 2 overdrives which is low rpms when the load is low.

 

[Wheelin98TJ]

What if I told you modern 8 and 10 speed autos are supposed to shift frequently? The latest corvette autos have 4 or 5 overdrive gears. Load goes up, even a little from a hill or a headwind and it's supposed to downshift. The OP is talking about 4.10s and 33s. Yes it will still downshift up a small hill, by design. If your axle gears are so low that it holds 8th under increased loads it is geared too low. It isn't supposed to. It never was. And geared that low you've eliminated the benefit of having 2 overdrives which is low rpms when the load is low.

I own an 8 speed and a 10 speed.

My 10 speed does not shift frequently unless you're on the gas.

 

[Zachanadandy]

I own an 8 speed and a 10 speed.

My 10 speed does not shift frequently unless you're on the gas.

Neither did the 8 speed in the ram with a 5.7L because there was enough torque at 2k rpm it didn't need to. I'm sure the 392 down shifts even less. With an engine that makes peak torque at over 4k rpms and peak horsepower at over 6k the only way to keep it from downshifting would be to constantly run it at 3k+ rpms. That's just dumb. Who cares if it downshifts when it needs more power so long as it still runs low rpms when it doesn't? That's what it should do.

 

[professorkx]

2024 Rubicon, 4.10, 37’s, 2.5” lift. My rig can hold 80mph easily in varied terrain in the Pacific NW with overland camping gear in the bed. I don’t recall ever looking at which gear my transmission was in…I just left the engine/transmission do its thing and enjoy driving my rig…and get 16.5 mpg at 80mph.

Not sure why folks are obsessed with staying in 8th gear. Even in my corvette with 6 speed manual I have to shift down, and it has a ton my HP under the hood than my Gladiator.

 

[Wheelin98TJ]

2024 Rubicon, 4.10, 37’s, 2.5” lift. My rig can hold 80mph easily in varied terrain in the Pacific NW with overland camping gear in the bed. I don’t recall ever looking at which gear my transmission was in…I just left the engine/transmission do its thing and enjoy driving my rig…and get 16.5 mpg at 80mph.

Not sure why folks are obsessed with staying in 8th gear. Even in my corvette with 6 speed manual I have to shift down, and it has a ton my HP under the hood than my Gladiator.

There is someone obsessed with staying in 8th gear? That is weird.

 

[Her mojave]

And 35s at least.. on the X you cant even get 35s...why just why

 

[ShadowsPapa]

I own an 8 speed and a 10 speed.

My 10 speed does not shift frequently unless you're on the gas.

Then you live in a flat area, or where entrance ramps are long and there's little traffic or it has an engine with more torque.
A 10 speed may not shift as frequently depending on the engine abilities and torque output requested of it.
Our JLU 4xe shifts less frequently than the JT - same transmission, it's all about the engine supplying the power.
We have driven the same routes from here to FL with each of our Jeeps - the JT has to shift a lot - it's supposed to. The 4xe - shifts maybe half as much, literally. It doesn't need to.

I see 8th more often with my Mojave but then the 4.10 gearing helps in that respect, vs. the 3.73 of my prior 2 JTs.
If there's a wind (it's always windy here) or a hill (it's hilly here), then I might go miles in 7th and hit 8th when I hit the flats or the wind isn't in my face.

They also have to gear these, again, to the numbers they have to abide by or be fined.
But for me, the 4.10s work great, for heavy loads and hills - that's what a transmission is for. Since 8th is the second overdrive gear, people shouldn't get so hung up on whether it's there or not.
Of course there's those who add weight, change tires, wheels, fender flares, add massive amounts of wind resistance then talk about lack of seeing the higher gears - just ignore those cases.

 

[Badunit]

...The only way to keep it from downshifting would be to constantly run it at 3k+ rpms.

That's not quite true. You just need to get it above 2000 rpm to make a big difference. Maybe 2200 at interstate speeds.

Modern vehicles are geared so high they are barely above idle in high gear. There is almost no torque there so they have to downshift for just about everything. It should be called "coasting gear" or "flat terrain gear" because that's about all it is good for. Maybe they are designed to downshift all the time but that doesn't mean we have to accept it. We modify/improve everything else to fit our particular needs/desires/preferences. Why not this, too?

 

[Zachanadandy]

That's not quite true. You just need to get it above 2000 rpm to make a big difference. Maybe 2200 at interstate speeds.

Modern vehicles are geared so high they are barely above idle in high gear. There is almost no torque there so they have to downshift for just about everything. It should be called "coasting gear" or "flat terrain gear" because that's about all it is good for. Maybe they are designed to downshift all the time but that doesn't mean we have to accept it. We modify/improve everything else to fit our particular needs/desires/preferences. Why not this, too?

You spent $3k to turn 8th gear into 7th gear and deleted any benefit of 2 overdrives and then convinced yourself that you made it better because it shifts less? How is it better? Push on the throttle to pass and it still downshifts. Who cares if it shifts to 7th instead of 6th or 6th instead of 5th depending on the load and just how hard you're trying to accelerate? Even if 8th is only a coasting gear (which is hardly true with stock height/tires), you never coast? Coming back from Vegas there's a nearly 20 mile long, straight stretch of freeway that's all downhill. 8th gear, under 2k rpms, at 85mph for 20 miles and you're trying to tell me it would somehow be better if I spent $3k and turned an extra 400 rpm down that hill? Even if it would be better, I could manually shift into 7th and have the exact same gearing as 5.13s in 8th...for free. This 8 speed doesn't need more gearing period. 1st gear is the same as most other autos before the 8 and 10 speeds when those trucks/Jeeps were geared 5.38. Go back to the early JK, TJ, or XJ era and your 4.10s and the 4.7 1st gear are equal to one of those rigs on 6.72 axle gears. And yet you want me to believe I need more gearing to run 33s? Not remotely. I use the mojave on the desert, where there are no asked limits. It sees 8th on the dirt with stock 4.10s and 37s. Being our 3rd modern Jeep with this transmission, and having run over a half dozen tire and gear combos I will say the shifting is a little better with 4.56s and 37s. Even there acceleration was the same. If regearing was free I'd do it. $3k so it will hold 8th a under a little more load, have the same acceleration, and the same fuel economy? Nope.

 

[ShadowsPapa]

Maybe they are designed to downshift all the time but that doesn't mean we have to accept it

LOL - of course we all know more than the years of research, and experienced engineers and testing testing testing that goes into these things.
I think too many grew up with 3 and 4 speed manuals.
This is 2025 not 1975.

 

[DirectHit]

I'm on 37x13.5s and after 3k miles on the factory 4.10s, I just had it re-geared to 5.13s. It’s the best 3k I’ve spent on this money pit.

 

[Badunit]

You spent $3k to turn 8th gear into 7th gear

Also not true. Closer to 7 1/2.

For the rest of your post, you do you and I'll do me. Your use case is not the same as mine. Your preferences are not the same as mine.

LOL - of course we all know more than the years of research, and experienced engineers and testing testing testing that goes into these things.

Sure... these are the most perfect vehicles ever designed and built by mankind. We are at the pinnacle of perfection and only a fool would mess with it. Or maybe the manufacturer was trying to squeeze out a few more tenths of a mpg at the behest of government rules and regulations and the tradeoff was a decrease in driveability, while I have the opposite idea.

Actually, I am confounded why this is such a controversial topic. There are a wide range of mods made by so many people and for some reason gearing and the oil threads bring out such opposite and hard-set opinions, as if it was politics or religion.

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