Re-gearing Question

egclassic

egclassic

TJ Enthusiast
Joined
Nov 16, 2016
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Location
Cincinnati, OH, United States
I have a 2000 TJ Sport 4.0 Auto with the stock 3.07 gears with 32" tires on a 2.5" lift.
I've know this thing needs re-geared since I've bought it 5 or so years ago but have been procrastinating. It is not my daily Driver so it always takes the back seat to other projects.
Sorry, but I'm no gear head so excuse my ignorance here. What can I expect out of having it re-geared properly? Will it get better GPM's, take off better etc. This thing absolutely sucks on the highway. Sometimes I drive it to work, just to keep her in shape, and regret it as soon as I hit the highway.
We have a couple of dedicated jeep shops around here, and I want to be informed before I start getting quotes. Use will mostly be road driving, occasional light trails, no rock crawling or anything. What gearing would you all recommend for this setup? I do not plan to go any bigger on lift or tires. What should be done "while they are in there", what don't I need if they try to up-sell shit?
Thanks!
 
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egclassic said:
I have a 2000 TJ Sport 4.0 Auto with the stock 3.07 gears with 32" tires on a 2.5" lift.
I've know this thing needs re-geared since I've bought it 5 or so years ago but have been procrastinating. It is not my daily Driver so it always takes the back seat to other projects.
Sorry, but I'm no gear head so excuse my ignorance here. What can I expect out of having it re-geared properly? Will it get better GPM's, take off better etc. This thing absolutely sucks on the highway. Sometimes I drive it to work, just to keep her in shape, and regret it as soon as I hit the highway.
We have a couple of dedicated jeep shops around here, and I want to be informed before I start getting quotes. Use will mostly be road driving, occasional light trails, no rock crawling or anything. What gearing would you all recommend for this setup? I do not plan to go any bigger on lift or tires. What should be done "while they are in there", what don't I need if they try to up-sell shit?
Thanks!
Click to expand...

Regearing should improve both mpg and acceleration. Is your transmission the 32rh 3 speed? If so I believe the general consensus on this forum would be 4.10 gearing would be about the best you can do, any deeper than that and your highway rpms are going to be too high with that trans.
 
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Throwing out another thought %Wondering if a donor vehicle axles out a wrecking yard would be a more affordable option. Later years ran 3:73’s or a 4:10 out of a 2.5 . If swapping an axles are in your wheel house of skill it would for sure be the most affordable option, But you could also ask the Jeep shops opinion on doing the work. Those dedicated Jeep shops might have some take offs as well
 
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I've got a manual (five gears) and 235/85R16 tyres. That's about 31.7 inch. I re-geared it to 4.10 and the TJ runs like a sports car. Sometimes I miss the 6th gear but then I drive up some hill and think yeah nah, I'm happy :D
 
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andyj said:
I've got a manual (five gears) and 235/85R16 tyres. That's about 31.7 inch. I re-geared it to 4.10 and the TJ runs like a sports car. Sometimes I miss the 6th gear but then I drive up some hill and think yeah nah, I'm happy :D
Click to expand...

I'm planning to regear mine to 4.10s as well soon. I'm currently on 33s and 3.73 gears and I'm not sure whether to expect that to make much of a difference performance wise?

What were you originally geared at?
 
GregBelleville said:
I'm planning to regear mine to 4.10s as well soon. I'm currently on 33s and 3.73 gears and I'm not sure whether to expect that to make much of a difference performance wise?

What were you originally geared at?
Click to expand...

I regeared 3.73 to 4.10 , It is noticeable and the mileage is the same . However don't expect it to run like a 6.0 LS swap.
I may have seen more of a difference due to commuting in the mountains most of the time. I am glad I did it , If the Jeep was just a toy and not commuting you could gear much lower and get by , ( 4.88 or 5.13 ) . I didn't want to hassle with high driveshaft speeds etc on the highway.
 
GregBelleville said:
Regearing should improve both mpg and acceleration. Is your transmission the 32rh 3 speed? If so I believe the general consensus on this forum would be 4.10 gearing would be about the best you can do, any deeper than that and your highway rpms are going to be too high with that trans.
Click to expand...

4.10 is what I was thinking, it is the 32rh transmission.
Got to start calling a couple shops to see what this is going to cost me. This would be an ideal winter project since I live in Ohio and don't like taking it out in the salt.
 
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ColoJeep said:
I regeared 3.73 to 4.10 , It is noticeable and the mileage is the same . However don't expect it to run like a 6.0 LS swap.
I may have seen more of a difference due to commuting in the mountains most of the time. I am glad I did it , If the Jeep was just a toy and not commuting you could gear much lower and get by , ( 4.88 or 5.13 ) . I didn't want to hassle with high driveshaft speeds etc on the highway.
Click to expand...

Yeah I'd be curious to hear if anyone has tried 4.56 gears with the 32rh on 33s or 35s and what the street driving manners were like. My Jeep isn't my daily, but I still want to be able to drive it to and from the trails, which could be 3 hours on the highway at times.
 
egclassic said:
4.10 is what I was thinking, it is the 32rh transmission.
Got to start calling a couple shops to see what this is going to cost me. This would be an ideal winter project since I live in Ohio and don't like taking it out in the salt.
Click to expand...

Are you doing lockers as well? Now would be the time to do it if you're already regearing.
 
GregBelleville said:
Are you doing lockers as well? Now would be the time to do it if you're already regearing.
Click to expand...

That's what I'm looking for is ideas of what I should do. Again, excuse my ignorance here but if i don't really do alot of off-roading, do I need lockers?
To be honest, there aren't a whole lot of trails around here, unfortunately. There are some that are a couple hours away, but I cringe at the thought of "driving" it that far on a highway at this point. Maybe after it's geared right.
 
egclassic said:
That's what I'm looking for is ideas of what I should do. Again, excuse my ignorance here but if i don't really do alot of off-roading, do I need lockers?
To be honest, there aren't a whole lot of trails around here, unfortunately. There are some that are a couple hours away, but I cringe at the thought of "driving" it that far on a highway at this point. Maybe after it's geared right.
Click to expand...

Going from 3.07s to 4.10s is going to be a huge improvement for you, especially on the highway. If you don't plan on getting into more difficult wheeling then the additional cost of lockers may not be worth it for you.
 
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GregBelleville said:
Yeah I'd be curious to hear if anyone has tried 4.56 gears with the 32rh on 33s or 35s and what the street driving manners were like. My Jeep isn't my daily, but I still want to be able to drive it to and from the trails, which could be 3 hours on the highway at times.
Click to expand...

4.56 is the common choice for 35’s on 32RH, tons of those experiences floating around, especially on the other forums from 10-15 years ago. There are a few of those with 33’s and they rev about 200 rpm higher on the highway. Ends up around 3200 or 3400 at 70.

With 32’s is definitely do 4.10. That combo is practically identical to 4.56/35s. 4.10/33s is slightly worse, but is still good and “proper.”
 
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