Re-gear done (amazing)

CptnMurica

CptnMurica

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After spending a lot of time in here reading all the info I went for 4.56s. I have to say that this is great. My 4 hamsters have come alive. 4wdl is a bulldog On the trail. Off the line it goes. And keeps up with traffic. Picked up around 4mpg. It’s pricey but if ya haven’t done it and your running over sized tires this is where it’s at. 👌

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I drove on 35s and 4.10s for a few months before regearing. I've lost MPGs after moving to 5.13s. :cautious:
To be fair, the LJ is so much more fun to drive with the 5.13s that it's hard to keep my foot out of it. :LOL:
 
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R3ID05TJ said:
Any reason you didn't go 4.88?
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I’m just a tween build. Trying to stay middle of the road. Even tho I’m 90% dedicated wheeler. Im satisfied. But I know I could’ve went 4.88. Tryin not to think about it. We all know how difficult that is.
I just bought a 98zj 6 cylinder in great shape. Im gonna make that my baby. And 4.88 that one.
Big rear axel arb etc.
now that I’ve taken my lumps on this one.
That being said my tj is great. Love it.
 
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My LJ regearing is scheduled. Looking forward to it. Right now I have to drive my 4sd like a 3sp - 4th is utterly useless (I just have to remember to hit the OD switch every time I leave town). That said, I assume having 3 lower gears instead of 2 will also help performance at lower speed a lot. Only one good thing I can say about my current gearing - doing 80 in third is no problem, plenty of power band left.
 
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mousehunter said:
My LJ regearing is scheduled. Looking forward to it. Right now I have to drive my 4sd like a 3sp - 4th is utterly useless (I just have to remember to hit the OD switch every time I leave town). That said, I assume having 3 lower gears instead of 2 will also help performance at lower speed a lot. Only one good thing I can say about my current gearing - doing 80 in third is no problem, plenty of power band left.
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You will be pleasantly happy with it. For sure. Best mod on jeep. Less winch
 
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mousehunter said:
My LJ regearing is scheduled. Looking forward to it. Right now I have to drive my 4sd like a 3sp - 4th is utterly useless (I just have to remember to hit the OD switch every time I leave town). That said, I assume having 3 lower gears instead of 2 will also help performance at lower speed a lot. Only one good thing I can say about my current gearing - doing 80 in third is no problem, plenty of power band left.
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What size are your tires and what gear ratio are you going for?? I'm going with real 32" tires and debating whether to go with 4.88 or 5.13. Want the best fuel economy with the current gas prices looking to be permanent. Both ratios are way lower than the stock gearing. in 4 o/d.
 
My jeep came with 35"x12". I currently have 33"x8.5" on it. Gas milage is depressingly terrible. On a 400 mile trip last weekend I think I got about 12mpg (maybe a bit less, like 10mpg). I currently have 3.73 gears, going to get 5.13. I was not expecting good gas mileage on the interstate.

That 400 mile trip is basically a full tank on my F250 (28 gallons)- abet I usually fill up during it, as Buckee's has cheeper diesel, and I don't mind the pit stop and I don't trust pulling into home on fumes. I went through about 2.5 tanks to do it in the Jeep. 120 miles or so was 3/4 tank (16 gallon tank I think) . I topped off my tank before I started, and had to fill up coming and going at a Buckee's (Bay City on the way out, Katy on the way home). It probably did not help my gas milage that I had a 1.5hr traffic delay in Houston on the way to the beach - all east bound lanes of I-10 were shut down and the detour required crossing a rail road track with a train parked on it.

It is really sad that I can probably tow the Jeep with my truck and use less fuel than driving the Jeep by itself. I think I got 14mpg with my truck towing the Jeep home from Oklahoma (10hr drive).
 
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I am not really crying about the mpg. Everyone mentions it is a box on wheels. That said, my wife's first JLU got about 20 mpg. I think her current one gets 24mpg. In effect it is close enough to our 11 year old minivan that it is a wash. Yeh, I know it is not a fair comparison. The current JLU is a diesel. My diesel VW tagged 45 before the the Goverment mandated neutering. That said the diesel F250 has never gotten better than 16. I probably should consider deleting it, but that would be illegal...
 
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mousehunter said:
I am not really crying about the mpg.
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Just to be clear my edit wasn't a personal dig at you but rather a correction of the record. Even in OEM configuration my LJ got shit gas mileage. When I had it lifted and put 35s on it ... fuhgeddaboudit. I retired it from daily driver status and bought a Civic.
 
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I just did a re-gear from 3.73 to 4.56. 4.0 w/ NV3550 with 33's.

It's a whole new ride. All shifts are cleaner and more natural feeling. I can run around town in 3rd at 2800 and have just enough of the torque curve left to get up and go, or drop it in 4th and cruise at 2200 on the right side of the torque curve.

I travel over the local causeway that has few bridges that have decent climbs and in the past I had to drop it into 4th, sometimes 3rd depending on the wind. Now at 55-ish in fifth I step on it and it goes.

Might 4.88's been better? Not sure. I doubt I will ever go to 35's so opted for 4.56 to get as close to factory as possible. Feels much crisper. I got back 5th and it looks like I picked up half to a full mile per gallon depending on how I am driving. Added TrueTrack LSD's at the same time. Well worth the money.
 
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I have now 4.56 gears, 42RLE (4 speed auto), 4.0 engine and 31 inch tires (BF Goodrich 31x10.5R15).
it drives great, the overdrive works perfectly fine. Getting precisely 2500RPM at 70MPH. It accelerates fine, can drive 70MPH on highway really well.

Previously with 3.73 gears, it felts like a dog, making the overdrive barely useful.
One thing that I am sorry about, is that I didn’t go deeper into gears and didn’t go to 4.88 or 5.13 gears. I think that the best performance (and possibly worst fuel economy) would be at 2700RPM at 70MPH.
 
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roverhi said:
What size are your tires and what gear ratio are you going for?? I'm going with real 32" tires and debating whether to go with 4.88 or 5.13. Want the best fuel economy with the current gas prices looking to be permanent. Both ratios are way lower than the stock gearing. in 4 o/d.
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Not having a proper gear is actually wasting more gas not less. Before regearing, I would burn more gas to maintain 70MPH. Taking into account that you have 4 speed and plan to do real 32’’, you might want to do 5.13.
If you want to save gas, just stay under 65MPH. It really starts to burn gas like crazy when you do 70+ MPH
 
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MikekiM said:
I just did a re-gear from 3.73 to 4.56. 4.0 w/ NV3550 with 33's.

It's a whole new ride. All shifts are cleaner and more natural feeling. I can run around town in 3rd at 2800 and have just enough of the torque curve left to get up and go, or drop it in 4th and cruise at 2200 on the right side of the torque curve.

I travel over the local causeway that has few bridges that have decent climbs and in the past I had to drop it into 4th, sometimes 3rd depending on the wind. Now at 55-ish in fifth I step on it and it goes.

Might 4.88's been better? Not sure. I doubt I will ever go to 35's so opted for 4.56 to get as close to factory as possible. Feels much crisper. I got back 5th and it looks like I picked up half to a full mile per gallon depending on how I am driving. Added TrueTrack LSD's at the same time. Well worth the money.
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Very nice! 3.73 here also on 31s, I image going to 4.10 wouldn't be that much of a change. Would like 33s eventually & the truetrac as well.
I have been running around in 4th trying to get out of the habit of hitting 5th on the surface streets around 45 mph and turning like 1500 rpm. 4.56 would probably be the way to go.
 
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Pantera99 said:
Very nice! 3.73 here also on 31s, I image going to 4.10 wouldn't be that much of a change. Would like 33s eventually & the truetrac as well.
I have been running around in 4th trying to get out of the habit of hitting 5th on the surface streets around 45 mph and turning like 1500 rpm. 4.56 would probably be the way to go.
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Fifth was useless for me.. dead flat roads or downhill would be the only time I could use it. If you plan is to go to 33's, or if it is even a remote possibility then got to 4.56. If you do 4.10 and then add 33's, odds are you not redo the gears to 4.56.. you'll just live with it underperforming. Need some forward thinking.
 
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