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Old 02-25-2012, 08:15 PM   #61
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Quote:
Originally Posted by chris.george
Man kbwwolf, all I gotta say is: if you get anything greater than 4.10 you better get out of first gear fast
No different than my 07.

First gear is non existent with 4.10's.
Sometimes I find it easier to start in 2nd

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Old 02-25-2012, 08:22 PM   #62
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Originally Posted by Yella View Post
Is there an easy formula for converting rpm from that chart with different speeds? In other words, how did you figure 2700 @ 60?
Okay...here's the scoop on your rpms @ 60 mph (since that's about where you max out) in the following gears, based on calculator I linked you to above:

3.21: 1523 rpms...man, you get toilet paper stuck to your tire, and you're in trouble.

4.56: 2163 rpms...that's better, but still not ideal.

4.88: 2315 rpms...for the way you described driving your rig, this is what I would recommend.

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Old 02-25-2012, 08:23 PM   #63
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Originally Posted by kjeeper10 View Post
No different than my 07.

First gear is non existent with 4.10's.
Sometimes I find it easier to start in 2nd
Edit: that video was doing fun things with the HTML.


Ha ha, on a sidenote, with as fast as we reply to each this may as well be IRC.
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Old 02-25-2012, 08:24 PM   #64
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Originally Posted by kjeeper10 View Post
No different than my 07.

First gear is non existent with 4.10's.
Sometimes I find it easier to start in 2nd
No doubt. In fact, it snowed here yesterday, not enough to go 4H. I don't think I used first gear all day.
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Old 02-25-2012, 08:27 PM   #65
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Originally Posted by chris.george



Ha ha, on a sidenote, with as fast as we reply to each this may as well be IRC.
Classic TV
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Old 02-25-2012, 10:22 PM   #66
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Pretty informative little doohickey, IMO.
That little doohickey is AWESOME! Slicker than bull snot I tell ya.
I've been staring at this for 2 hours. The wife thinks I've fallen asleep at the computer.

I need to regear. 4.56 or 4.88, not sure just yet. I feel relieved and didn't realize I needed relieved.

Thanks man. Thanks to all of you for your help.
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Old 02-25-2012, 10:23 PM   #67
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That little doohickey is AWESOME! Slicker than bull snot I tell ya.
I've been staring at this for 2 hours. The wife thinks I've fallen asleep at the computer.

I need to regear. 4.56 or 4.88, not sure just yet. I feel relieved and didn't realize I needed relieved.

Thanks man. Thanks to all of you for your help.
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Old 02-25-2012, 11:57 PM   #68
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Now that I know about what I need, where do I get it? Does someone like Quadratec have a complete package to replace gears? This is probably one of those things that everyone will say has to be done by a professional. How could I show my son how to do it if it's done in a shop? I'm a bit of a professional myself. Started out as a machinist years ago and moved into the maintenance field. Pushing pencils nowadays but I would still like to entertain the idea of doing this project myself.
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Old 02-26-2012, 08:45 AM   #69
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Originally Posted by Yella View Post
Now that I know about what I need, where do I get it? Does someone like Quadratec have a complete package to replace gears? This is probably one of those things that everyone will say has to be done by a professional. How could I show my son how to do it if it's done in a shop? I'm a bit of a professional myself. Started out as a machinist years ago and moved into the maintenance field. Pushing pencils nowadays but I would still like to entertain the idea of doing this project myself.
Yup! Take a look at the Vendor's here. I'm sure if you called they would love to help you out!

Also talk to your mechanic (if you've picked one) to make sure they knew what you need, etc too.


Also I use this for a reference a lot:
Gearing
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Old 02-26-2012, 09:07 AM   #70
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Originally Posted by Yella View Post
Now that I know about what I need, where do I get it? Does someone like Quadratec have a complete package to replace gears? This is probably one of those things that everyone will say has to be done by a professional. How could I show my son how to do it if it's done in a shop? I'm a bit of a professional myself. Started out as a machinist years ago and moved into the maintenance field. Pushing pencils nowadays but I would still like to entertain the idea of doing this project myself.

You can get gear sets through Northridge 4x4:

Northridge4x4 Jeep Parts Online Store

Click on "axles and gears"...they carry the major brands, such as Yukon, Superior and USA Standard. From what I've read, Yukons are the most widely-used among Jeepers.

Yukon Gear & Axle
Superior Axle & Gear
USA Standard Gear. Products.

You want to order a master kit, since some of the parts, such as the pinion nut, are likely to be trashed during removal of your stock gears. You need to do front and rear. Most of the time I advise people to find a shop with a lot of experience changing gear sets. One of the reasons for this is that, if something goes wrong, using a reputable shop will often keep the mfr warranty intact. If you do it yourself and botch it, the mfr will probably not honor the warranty.

That said, if you and your son wanna take it on, why not?

Here's a link to a thread I started on gears last year, when I first started looking into the whole process. Oilwell's posts (#23 and #31) have some good info as to what's necessary to do the job:

Gearing for a 2012 MANUAL
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Old 02-26-2012, 10:43 AM   #71
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I'm sill confused about some of the regearing desires, especially with the '12s and with manuals.

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Originally Posted by kjeeper10 View Post
No different than my 07.

First gear is non existent with 4.10's.
Sometimes I find it easier to start in 2nd
You all seem to concede that first gear with the 4.10s is already too low to be useful. By regearing even 19% lower by getting 4.88s, you're making your first gear completely obsolete (you definitely won't need it in 4WL). And you're literally taking away your high-end gearing, which you might want under some conditions. For example, with my '12 auto with 3.73s, at 70 mph, I'm hitting about 2,100 rpms. On level ground, that seems pretty good with that engine. It requires very little throttle to keep it going at that speed on level ground. I definitely would not want that gear ratio to go down by 30% to 4.88 with my rpms jumping up to 2,800 rpms or so. Certainly not all of the time, with no option ever of upshifting.

And (and here's the big curiosity to me), I can go down to a gear ratio like that right now if I want anyway by down-shifting, and I don't even have a manual.

If you go from 4.10s to 5.13s with a manual, you're lowering your gear ratio by 25.1%. When you have 4.10s and downshift from 6th to 5th, you're lowerering your gear ratio by 25.5%. It's like having "5.14" gears. And you still have sixth gear if you want it, and also a first gear that's not way too low.

Am I missing something? I probably am.
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Old 02-26-2012, 12:29 PM   #72
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Originally Posted by MarineHawk View Post
I'm sill confused about some of the regearing desires, especially with the '12s and with manuals.

You all seem to concede that first gear with the 4.10s is already too low to be useful. By regearing even 19% lower by getting 4.88s, you're making your first gear completely obsolete (you definitely won't need it in 4WL). And you're literally taking away your high-end gearing, which you might want under some conditions. For example, with my '12 auto with 3.73s, at 70 mph, I'm hitting about 2,100 rpms. On level ground, that seems pretty good with that engine. It requires very little throttle to keep it going at that speed on level ground. I definitely would not want that gear ratio to go down by 30% to 4.88 with my rpms jumping up to 2,800 rpms or so. Certainly not all of the time, with no option ever of upshifting.

And (and here's the big curiosity to me), I can go down to a gear ratio like that right now if I want anyway by down-shifting, and I don't even have a manual.

If you go from 4.10s to 5.13s with a manual, you're lowering your gear ratio by 25.1%. When you have 4.10s and downshift from 6th to 5th, you're lowerering your gear ratio by 25.5%. It's like having "5.14" gears. And you still have sixth gear if you want it, and also a first gear that's not way too low.

Am I missing something? I probably am.
Actually, for me anyway, first gear is plenty useful. Moreso off-road than on, but I use it in both conditions. If the roads are really slick with ice or snow I don't use it much, but other than that...

I understand your assertion that you can downshift to a lower gear on the freeway and put yourself more into the powerband, but then what's the point of having the higher gear?

With my 3.73's and 34" (actual) tires, my Jeep's fine on flat ground. It labors a little to pass, and if I need to accelerate quickly I'll often downshift to 5th gear to get it done. On hills, it's the same thing. The other day we had 30-40 mph winds here (not uncommon in WI in winter), and driving into it was 5th gear exclusively. 6th wasn't even an option.

On my '12 manual with 34" tires and 3.73 gears, here's what I turn:

1644 rpm in 1st gear @ 10mph
2056 rpm in 6th gear @ 70mph

Crawl speed (in feet per minute, in low): 197 fpm @ 1000rpm in 1st gear

No problems with first, obviously. But 6th gear is underpowered, plain and simple, as evidenced NOT by looking at the #'s, but by driving it everyday in the real world. However, since the #'s are what I'll have to go by when looking at lower gears, we'll use them as a point of reference.

Same setup with 4.56 gears:

2010 rpm in 1st gear @ 10mph
2514 rpm in 6th gear @ 70mph

Crawl speed: 161 fpm @ 1000rpm in 1st gear

THAT is probably about where I wanna be. However, that's assuming I can get the 4.56 gears when it comes time to make the switch (there are availability issues sometimes with the 4.56's).

Same setup with 4.88 gears:

2151 rpm in 1st gear @ 10mph
2691 rpm in 6th gear @ 70mph

Crawl speed: 150 fpm @ 1000rpm in 1st gear

Granted, that's a little much. At least for me. Looking at it in the way I just laid it out, I'd have to admit that, if I can get 4.56 gears when it comes time for the change, that's most likely the way I'll go.

Nevertheless, the #'s for the 4.88 gears wouldn't be bad at all if you lived in the Blue Ridge or Allegheny or Rocky mountains, IMO.

I hear what you're saying, and your argument is totally valid. It's just a matter of perspective. If you're fine with using a lower gear and having your high gear rendered unusable in certain situations, that's cool. I'd rather find a balance between a higher-strung 1st gear (with a slower crawl ratio), and still be able to utilize my 6th gear capabilities when I'm driving from Wisconsin to the East Coast, or to TX, or wherever.

I think, either way you go, it's a pretty fine line. If it wasn't, the decision would be easy.
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Old 02-27-2012, 10:02 PM   #73
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Excellent post Wolf. Makes a lot of sense. Thanks.
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Old 02-27-2012, 10:35 PM   #74
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Does first gear w/ 4.10's become more useful with bigger tires?
Or worse?
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Old 02-27-2012, 10:44 PM   #75
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I went with 35'' tires and a 3.25'' lift kit on my 2007 Wrangler with 4.10 gears. Why do I keep reading that I should take my Jeep out of overdrive? What is the benefit of that? Do you take yours out of overdrive, or does it really matter?
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Old 02-27-2012, 10:54 PM   #76
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Originally Posted by GoPacers
I went with 35'' tires and a 3.25'' lift kit on my 2007 Wrangler with 4.10 gears. Why do I keep reading that I should take my Jeep out of overdrive? What is the benefit of that? Do you take yours out of overdrive, or does it really matter?
Nobody says you have to.

Just so many people complain of lack of power passing on the freeway or driving up hill. All the while the auto tranny is in OD.
Shutting of your OD will keep the tranny in the lower gear-instead of laboring in OD higher in the RPM band.
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Old 02-27-2012, 11:06 PM   #77
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So you would recommend turning overdrive off on the interstate and not worrying about turning overdrive off in town?
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Old 02-28-2012, 12:40 AM   #78
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So you would recommend turning overdrive off on the interstate and not worrying about turning overdrive off in town?
I'm not sure of myself here, but, when I hit the gas on the highway, my auto trans kinda does the right thing. If I want to intervene on the hills, I can shift from my 3.73 gears in 5th gear down into 4th gear and have the equivalent of 4.49:1 (i.e., near 4.56:1) gears in fifth gear. Works for me.
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Old 02-28-2012, 10:29 AM   #79
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Does first gear w/ 4.10's become more useful with bigger tires?
Or worse?
It's not really a matter of better or worse.

With 4.10 gears and 31" tires (using actual tire sizes) @ 1000 rpm, your crawl speed would be 166 fpm.

With the same setup and 34" tires, it would be 182 fpm.

So, basically, you'd cover a little more ground with the larger tires, all other things being equal. It wouldn't be a big difference, either way, in terms of performance.

You'd be turning lower rpms (1783 @ 10 mph with the 34" tires, as opposed to 1955 @ 10 mph with 31" tires) so, in actuality, your first gear wouldn't "wind up" as high as it does now.

Not sure if this makes any sense or not.
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Old 02-28-2012, 10:54 AM   #80
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So you would recommend turning overdrive off on the interstate and not worrying about turning overdrive off in town?
OD is essentially an extra gear. In an auto tranny with 4 gears, overdrive acts as a 5th gear. When you reach a certain speed, it allows you to maintain that speed with lower rpm's, which improves gas mileage and reduces wear and tear on your engine.

When you run larger tires on your Jeep, the extra weight and rolling resistance robs you of engine power. If you don't compensate for this by regearing, you'll notice a decreased ability to pass on the freeway, climb long hills, etc.

It essentially makes your Jeep's OD ineffective. You'd be better off shutting it down, and using the lower gears (where the power loss isn't as extreme) for passing, hills, etc.

The downside to this, of course, is that your gas mileage will suffer.

The only real way to restore the effectiveness of your OD is to regear to an appropriate ratio that can handle the larger tires.
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Old 02-29-2012, 09:13 PM   #81
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I just want to step in here and give a bit of update on my experiences. With my '08, 6-speed manual I have been driving to work and back (28 miles one way) and forgetting I have a 5th and 6th gear. I just about forgot what it felt like to drive a vehicle that feels like it can compete on the highway. It's great; I can use the cruise control. I'm driving about 62 to 64 like I use to. I was driving 60 cause it just seems less of a hassle and easier to maintain. My rpm is staying around 2475. The engine sounds good and the exhaust sounds great (Banks cat back). I'm able to ease around the 18-wheelers without issues. After two days on a fill up with "regular" my mpg is telling me I am 1/2 to 1 mpg less and I do hear the engine ping but not anything like it was when I was struggling along at 1600 rpm. Of course I will put pencil to paper to get an accurate reading at the next fill up.

Here is what I am seeing driving only 4 gears with 3.21:
gear speed rpm
1 29 4000
2 49 4000
3 60 3250
4 64 2500

Here is what I would expect if I regear to 4.88
gear speed rpm
1 19 4000
2 32 4000
3 43 3500
4 50 3000
5 58 2750
6 62 2500

Here is a question: Driving in 4th gear at 2500rpm feels really good. Would it still feel the same if I regear to 4.88 and drive in 6th gear at 62?

The reason I ask is because now with 3.21 and driving in 4th my transmission ratio is 1.25. If I regear and drive in 6th the ratio will only be 0.84. Would that be a big difference?

I bet this question has been asked but I just didn't understand the importance of it.
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Old 02-29-2012, 09:35 PM   #82
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Quote:
Originally Posted by Yella
I just want to step in here and give a bit of update on my experiences. With my '08, 6-speed manual I have been driving to work and back (28 miles one way) and forgetting I have a 5th and 6th gear. I just about forgot what it felt like to drive a vehicle that feels like it can compete on the highway. It's great; I can use the cruise control. I'm driving about 62 to 64 like I use to. I was driving 60 cause it just seems less of a hassle and easier to maintain. My rpm is staying around 2475. The engine sounds good and the exhaust sounds great (Banks cat back). I'm able to ease around the 18-wheelers without issues. After two days on a fill up with "regular" my mpg is telling me I am 1/2 to 1 mpg less and I do hear the engine ping but not anything like it was when I was struggling along at 1600 rpm. Of course I will put pencil to paper to get an accurate reading at the next fill up.

Here is what I am seeing driving only 4 gears with 3.21:
gear speed rpm
1 29 4000
2 49 4000
3 60 3250
4 64 2500

Here is what I would expect if I regear to 4.88
gear speed rpm
1 19 4000
2 32 4000
3 43 3500
4 50 3000
5 58 2750
6 62 2500

Here is a question: Driving in 4th gear at 2500rpm feels really good. Would it still feel the same if I regear to 4.88 and drive in 6th gear at 62?

The reason I ask is because now with 3.21 and driving in 4th my transmission ratio is 1.25. If I regear and drive in 6th the ratio will only be 0.84. Would that be a big difference?

I bet this question has been asked but I just didn't understand the importance of it.


I understand with the 6 speed- we can essentially just drop a gear and up the Rpms.
There has to be more to it. "regearing"
Never quite understood that myself.

Good question.

Think I asked it before
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Old 02-29-2012, 11:31 PM   #83
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Originally Posted by Yella View Post
I just want to step in here and give a bit of update on my experiences. With my '08, 6-speed manual I have been driving to work and back (28 miles one way) and forgetting I have a 5th and 6th gear. I just about forgot what it felt like to drive a vehicle that feels like it can compete on the highway. It's great; I can use the cruise control. I'm driving about 62 to 64 like I use to. I was driving 60 cause it just seems less of a hassle and easier to maintain. My rpm is staying around 2475. The engine sounds good and the exhaust sounds great (Banks cat back). I'm able to ease around the 18-wheelers without issues. After two days on a fill up with "regular" my mpg is telling me I am 1/2 to 1 mpg less and I do hear the engine ping but not anything like it was when I was struggling along at 1600 rpm. Of course I will put pencil to paper to get an accurate reading at the next fill up.

Here is what I am seeing driving only 4 gears with 3.21:
gear speed rpm
1 29 4000
2 49 4000
3 60 3250
4 64 2500

Here is what I would expect if I regear to 4.88
gear speed rpm
1 19 4000
2 32 4000
3 43 3500
4 50 3000
5 58 2750
6 62 2500

Here is a question: Driving in 4th gear at 2500rpm feels really good. Would it still feel the same if I regear to 4.88 and drive in 6th gear at 62?

The reason I ask is because now with 3.21 and driving in 4th my transmission ratio is 1.25. If I regear and drive in 6th the ratio will only be 0.84. Would that be a big difference?

I bet this question has been asked but I just didn't understand the importance of it.
You'd have a little less snap in your acceleration, simply because of the difference in the gear ratios between 4th and 6th gears. However, you'd be using 6th gear much closer to what it would feel like on a stock '08, without the big-ass tires.

In other words, you'd be able to pass in 5th, and quite often in 6th, where right now you really can't do that in either one. The rpms you now have in 4th gear, you'd have in 6th, so it really wouldn't feel much different, though you'd have a little less horsepower at hand.

Overall, it could very well give you back some of the mileage you lost by going to 34" tires in the first place (although a lot of that is dependent on your driving, the terrain, your Jeep's upkeep, blah blah blah).

Just like with using OD on an auto transmission, you'd get better mileage and less wear and tear on your engine.

And if you really needed to scoot (not that Jeeps really do that ), say to get around some knob that cuts in front of you but happens to be going slow, you can just downshift and go.

In lower gears, you'll be shifting sooner than you're used to, simply because your speed to rpm ratio will be different. But overall, your Jeep's engine and tranny will be running about where they were designed to be, and I think you'll find it a definite improvement.
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Old 03-01-2012, 08:39 PM   #84
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Good question.

Think I asked it before
I thought it was a good question and I knew the answer. I just wanted to hear the wolfman put the answer in his words because like rics1997, he seems to be able to splain things in simple terms.

And you probably did ask that question before and I probably did read it before but I didn't understand the language to understand. I get it now. It's cool to think about. Before it hurt my head.
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Old 03-01-2012, 08:42 PM   #85
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Originally Posted by Yella

I thought it was a good question and I knew the answer. I just wanted to hear the wolfman put the answer in his words because like rics1997, he seems to be able to splain things in simple terms.

And you probably did ask that question before and I probably did read it before but I didn't understand the language to understand. I get it now. It's cool to think about. Before it hurt my head.


No s**t huh haha
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Old 03-01-2012, 09:01 PM   #86
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Originally Posted by kbwwolf View Post
You'd have a little less snap in your acceleration, simply because of the difference in the gear ratios between 4th and 6th gears. However, you'd be using 6th gear much closer to what it would feel like on a stock '08, without the big-ass tires.

In other words, you'd be able to pass in 5th, and quite often in 6th, where right now you really can't do that in either one. The rpms you now have in 4th gear, you'd have in 6th, so it really wouldn't feel much different, though you'd have a little less horsepower at hand.

Overall, it could very well give you back some of the mileage you lost by going to 34" tires in the first place (although a lot of that is dependent on your driving, the terrain, your Jeep's upkeep, blah blah blah).

Just like with using OD on an auto transmission, you'd get better mileage and less wear and tear on your engine.

And if you really needed to scoot (not that Jeeps really do that ), say to get around some knob that cuts in front of you but happens to be going slow, you can just downshift and go.

In lower gears, you'll be shifting sooner than you're used to, simply because your speed to rpm ratio will be different. But overall, your Jeep's engine and tranny will be running about where they were designed to be, and I think you'll find it a definite improvement.
Excellent post. You certainly came a long way since your thread "Gearing for a 2012 MANUAL". Was it JIMBO that asked what the hell we're doing in a 2012 thread learning about the 3.8? That was a good point but it just happened to be where I was when the light bulb clicked on.

Anyway, please explain your comment, But overall, your Jeep's engine and tranny will be running about where they were designed to be. Designed to be as in the geniouses that thought this system up on paper or the ones that decided to put 32's with a 6-speed and 3.21? Because the cool little gadget, the Gear Ratio Calculator tells me this:
1st @ 4000 = 27
2nd @ 4000 = 46
3rd @ 3250 = 56
4th @ 2500 = 60
5th = Useless
6th = Useless

I'm thinking the geniouses didn't have the ratio calculator and blindly threw this stuff together like I blindly purchased a used jeep that is a little inaduquate in off roading as well as on.

Am I looking forward to regearing this thing. Can't hardly wait. Damn taxes.
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Old 03-01-2012, 09:05 PM   #87
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Quote:
Originally Posted by Yella

Excellent post. You certainly came a long way since your thread "Gearing for a 2012 MANUAL". Was it JIMBO that asked what the hell we're doing in a 2012 thread learning about the 3.8? That was a good point but it just happened to be where I was when the light bulb clicked on.

Anyway, please explain your comment, But overall, your Jeep's engine and tranny will be running about where they were designed to be. Designed to be as in the geniouses that thought this system up on paper or the ones that decided to put 32's with a 6-speed and 3.21? Because the cool little gadget, the Gear Ratio Calculator tells me this:
1st @ 4000 = 27
2nd @ 4000 = 46
3rd @ 3250 = 56
4th @ 2500 = 60
5th = Useless
6th = Useless

I'm thinking the geniouses didn't have the ratio calculator and blindly threw this stuff together like I blindly purchased a used jeep that is a little inaduquate in off roading as well as on.

Am I looking forward to regearing this thing. Can't hardly wait. Damn taxes.
Easy answer would be its "power band"
The Rpm range where the engine doesn't lug and runs most efficient.
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Old 03-01-2012, 09:31 PM   #88
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still want the new wheels, anyone running stock tires with a 4.5inch backspace? Pros? Cons?

Im asking because im not set on the rise in tire size, but do want the option. So i'll need to go to a 17x9 with the 4.5 inch backspace. Or 17x9 with 5.25 backspace.

anyone?
PieFace, you never got your answer here. I'm not sure your original post was actually answered. The thread went down the road in the direction of regearing and you stated you did not want to regear. Are you still thinking no to regearing?

I can't help on your backspacing question. I purchased my wheels from a jeep on the showroom floor knowing what they would look like on my jeep therefore I didn't need to do any research.
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Old 03-01-2012, 09:42 PM   #89
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Originally Posted by Yella View Post
Excellent post. You certainly came a long way since your thread "Gearing for a 2012 MANUAL". Was it JIMBO that asked what the hell we're doing in a 2012 thread learning about the 3.8? That was a good point but it just happened to be where I was when the light bulb clicked on.

Anyway, please explain your comment, But overall, your Jeep's engine and tranny will be running about where they were designed to be. Designed to be as in the geniouses that thought this system up on paper or the ones that decided to put 32's with a 6-speed and 3.21? Because the cool little gadget, the Gear Ratio Calculator tells me this:
1st @ 4000 = 27
2nd @ 4000 = 46
3rd @ 3250 = 56
4th @ 2500 = 60
5th = Useless
6th = Useless

I'm thinking the geniouses didn't have the ratio calculator and blindly threw this stuff together like I blindly purchased a used jeep that is a little inaduquate in off roading as well as on.

Am I looking forward to regearing this thing. Can't hardly wait. Damn taxes.
I was talking about your rpm's after regearing to 4.88, and moreso in the higher gears than in the lower gears. First and second will be shorter than you're used to, but you'll gain usability in the higher gears, where currently you have none.

It's kinda like walking a tightrope...overbalance one way or the other, and you're SOL.

That's why you don't wanna OVERgear, any more than you wanna be undergeared. Undergearing makes your Jeep into a moped; overgearing will turn it into a go-kart.

Put in increments of 10 (out of simplicity, and since you max out around 60 mph on your daily commute), with 4.88 gears you'd be getting this:

1st @ 10mph: 2122
2nd @ 20mph: 2508
3rd @ 30 mph: 2460
4th @ 40 mph: 2315
5th @ 50 mph: 2411
6th @ 60 mph: 2315

Another way of putting it is, @ a constant rpm of 2500, your gears would run at 12, 20, 30, 43, 52 and 65 mph, respectively.

That kinda illustrates what I meant by the engine and tranny running closer to where they should be...like I said, it'll run a little higher in the low gears, but you'll get back the use of your high gears.

I consider that to be a worthwhile trade-off.

Not sure if that answers your question?
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Old 03-01-2012, 09:53 PM   #90
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It's really to bad you don't have an auto--and 5.38 gears

Mine turns 2250 rpm at 60 mph and 18.xx mpg-

Now, if I run up to the "slow" lane, 70 mph--it's 2600 rpm and drops to 17.xx mpg-

Sorry Charlie !

Everybody should have a manual !

Just kidding-

JIMBO

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