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Transmission's

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Old Jan 16, 2011 | 06:10 PM
  #1  
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From: Newton, Ks
Default Transmission's

If not in the right spot I appologize. Asking here since it deals with tires and gears. I am trying to decide on either a auto or manual transmission and need to know if one holds up better with say 5.13 gears and 35" tires.
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Old Jan 16, 2011 | 06:41 PM
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Are you talking about reliability? Or which would be more friendly with 35's and stock gears? Or if 5.13's are too small for crawling? Or something else.

For gearing, the charts above are a great place to start, but you will want more info to go with them. For reliability, you will find threads with problems on both, so I can't say that I would choose one over the other based strictly on the issues reported.


Here are the transmission ratio's, if it helps:

NSG 370—Manual, Six-Speed Overdrive
Gear Ratios 1st 4.46
Gear Ratios 2nd 2.61
Gear Ratios 3rd 1.72
Gear Ratios 4th 1.25
Gear Ratios 5th 1.00
Gear Ratios 6th 0.84
Gear Ratios Reverse 4.06

42RLE—Automatic, Four-Speed Overdrive
Gear Ratios 1st 2.84
Gear Ratios 2nd 1.57
Gear Ratios 3rd 1.0
Gear Ratios 4th 0.69
Gear Ratios Reverse 2.21


And the available axle ratio's are:
3.21, 3.73 and 4.10


As you'll see from the chart, manuals typically run around 500 rpm higher than auto's, given the same gears and tires.

As a quick comparison:
Auto, 5.13's, 35's = roughly 2380rpm @ 70mph
Manual, 5.13's, 43's = roughly 2358rpm @ 70mph
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Old Jan 17, 2011 | 06:26 AM
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So many combos to choose from!
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Old Jan 17, 2011 | 05:29 PM
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From: Newton, Ks
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nthinuf, what you had mentioned about life span of the transmissions with what was mentioned. if one say is stronger than the other over time. I have read a lot of your info on gearing and tires and it seems that you prefer the 5.13 gears in either trans with 35's in short is that about right or could a person run the 4.88's in a manual. I live in Ks and it looks like this ___________________,,,_____________ most of the time. I do plan on getting back to Colorado and hitting the trails at least once a year. I guess I am leaning towards a manual but just like the auto for lazy driving.
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Old Jan 17, 2011 | 05:57 PM
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Looking at the transmission ratio's above, you will see that they are completely different. So no, given the same size tires, I would not suggest the same ratio.

Manual with 35's, it is 4.88's if you do a lot of freeway, and 5.13's if you are mostly in town or off-road or plan to move up to 37's.

Auto with 35's, it is 5.13's if you have an X/Sahara, 5.38's if you have a rubicon.

(X's/Sahara's have a front D30 axle, and simply can not run 5.38's.
Rubicon 44's can run 5.38's)
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Old Jan 17, 2011 | 06:00 PM
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From: Newton, Ks
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Ok, thanks reading to much guess I am starting to get confussed
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Old Jan 17, 2011 | 06:11 PM
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It's easy to get confused, especially with so many different people giving opinions without actually reading what was asked or paying attention to the setup that the poster has.

I get annoyed when guys with manuals give gearing advice to guys with autos based only on their experience with a manual. You really need to drive an auto to understand just how pokey they are...
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Old Jan 17, 2011 | 06:14 PM
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i have a auto with 373 and 34" toyo mt 97lb.tire and a programmer and it works great
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Old Jan 17, 2011 | 07:07 PM
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From: Newton, Ks
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Thanks for the replys, helping out a lot.
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