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Those of you with manuals, what gear in 4lo?

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Old Mar 23, 2015 | 08:00 AM
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Default Those of you with manuals, what gear in 4lo?

I was playing around with 4lo this weekend (manual, 4:1 transfer case, 4.10 gears) and wasn't really sure what gear I wanted to be in in 4lo. 1st was nice descending steep/rocky hills but other then that it was too low of a ratio for anything else. 2nd was a little better those rpm's were starting to get high (over 3,000) on climbing long steep hills and less technical sections. Didn't really play around in 3rd because there was a grinding noise when going into gear. 4th seamed like the best gear to be in for less technical sections and around 10mph on the easy trails. Didn't try 5th or 6th because if I needed to go over 10mph I put it in 4hi.

Just curious what gear you guys are in when in 4lo for different terrains.
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Old Mar 23, 2015 | 10:04 AM
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It's going to vary by gear ratios and terrain. Most of what I do in my area is steep, rocky terrain so my 3.73's with the non-Rubi 2.73:1 transfer case and 33" tires is pretty much mandatory 1st gear in 4lo. That keeps me in enough power as to not lug the engine and also circulate fluids enough for adequate cooling. Not quite low enough for rock crawling, but I don't do much of that anyway.

Our other Jeep, which is a stock Rubi with 4.10's, is usually following me in 2nd gear in 4lo, sometimes 3rd depending on terrain. It's pretty easy for me to creep away from it.

In either case, 10-12mph is about the absolute max we'll run either Jeep in 4lo.
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Old Mar 23, 2015 | 03:53 PM
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Originally Posted by jk_sea
It's going to vary by gear ratios and terrain. Most of what I do in my area is steep, rocky terrain so my 3.73's with the non-Rubi 2.73:1 transfer case and 33" tires is pretty much mandatory 1st gear in 4lo. That keeps me in enough power as to not lug the engine and also circulate fluids enough for adequate cooling. Not quite low enough for rock crawling, but I don't do much of that anyway. Our other Jeep, which is a stock Rubi with 4.10's, is usually following me in 2nd gear in 4lo, sometimes 3rd depending on terrain. It's pretty easy for me to creep away from it. In either case, 10-12mph is about the absolute max we'll run either Jeep in 4lo.
Yea 2nd gear is like the sweet spot imo. 4th only got used in the easier stuff.
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Old Mar 23, 2015 | 04:11 PM
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I use 1st and 2nd for most everything in 4 lo (mostly rock).
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Old Mar 23, 2015 | 05:26 PM
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i use 1st gear 4lo for steep hill decends, mostly 3rd gear 4lo for the other stuff
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Old Mar 24, 2015 | 04:13 AM
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Originally Posted by anviljk
I was playing around with 4lo this weekend (manual, 4:1 transfer case, 4.10 gears) and wasn't really sure what gear I wanted to be in in 4lo. 1st was nice descending steep/rocky hills but other then that it was too low of a ratio for anything else. 2nd was a little better those rpm's were starting to get high (over 3,000) on climbing long steep hills and less technical sections. Didn't really play around in 3rd because there was a grinding noise when going into gear. 4th seamed like the best gear to be in for less technical sections and around 10mph on the easy trails. Didn't try 5th or 6th because if I needed to go over 10mph I put it in 4hi.

Just curious what gear you guys are in when in 4lo for different terrains.
First, as jk_sea said:
10-12mph is about the absolute max we'll run either Jeep in 4lo.

The whole point of 4L is lots of power at slow/crawling speed.
If you feel you need higher gears, better switch to 4H and use a lower gear.

The bottom line is the ratio between engine rpm and wheel rpm. You get about the same power (and engine rpm to wheel rpm ratio) by a high gear in 4L and a lower gear in 4H.
The Jeep will thank you for driving it in 4H and a lower gear, and not the other way around.

I use 4L only when it's really necessary.
The same goes for lockers.
I change back to 4H (or unlock the lockers) as soon as they aren't needed.

Last edited by GJeep; Mar 24, 2015 at 04:17 AM.
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Old Mar 24, 2015 | 06:02 AM
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If I am on a trail then I am in 4lo and just use whatever gear feel comfortable for the situation. That means usually in 1st or 2nd. If I don't need to be in 4lo then I am in 2wd. I only use 4hi on snowy or loose gravel roads when traction is questionable.
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Old Mar 24, 2015 | 11:59 AM
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Originally Posted by genesbro
If I am on a trail then I am in 4lo and just use whatever gear feel comfortable for the situation. That means usually in 1st or 2nd. If I don't need to be in 4lo then I am in 2wd. I only use 4hi on snowy or loose gravel roads when traction is questionable.
Unless it's a short, easy and familiar trail section, I air down and shift to 4H right after getting off the asphalt.
I air down to 20psi even on easy trails, because the ride is more pleasant, the Jeep gets less vibrations, braking is improved, and tire wear is reduced.

I don't know the trails you drive on, but over here, on unfamiliar trails (which, may even be marked on the map 'for any car'), or even very familiar trails, new obstacles do pop up.
It may be rocks or branches that collapsed onto the trail, or water that dug a pretty deep ditch across the trail, or whatever.
Or, someone on a bike may recklessly speed on the trail, forcing me to get 2 wheel off the trail to prevent collision -- in which case, there may be no time to change to 4H.

This is what water did, in one winter, to a trail which used to be a wide "trail highway": (I drove across it back & forth just for fun)

Click image for larger version

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Another reason for using 4H on easy trails is the tires.
Tires slip a little bit all the time, on asphalt too, whenever we accelerate, or turn, or brake.
I don't mean sliding, I mean small unnoticeable slip, which is part of how tires behave.
On soil, even hard soil, they slip much more than on asphalt. This slip is a major cause for tire wear.
In 4H, as the push is divided between more wheels, they slip less when accelerating, than in 2 wheel drive, so tire wear is reduced.

Last edited by GJeep; Mar 25, 2015 at 01:28 AM.
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Old Mar 25, 2015 | 01:49 PM
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Originally Posted by genesbro
If I am on a trail then I am in 4lo and just use whatever gear feel comfortable for the situation. That means usually in 1st or 2nd. If I don't need to be in 4lo then I am in 2wd. I only use 4hi on snowy or loose gravel roads when traction is questionable.
I agree 100%. I can't say that I've ever used 4H on a trail. Snowy and icy roads only, and perhaps sometimes on slick gravel/dirt (mud) roads where the tires are apt to sink in a bit.
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Old Mar 25, 2015 | 02:10 PM
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Edit: Nevermind - I don't agree with running in 4wd for the reasons of maneuvering around incidents; no, I think speed reduction is the primary factor there, and 2wd is appropriate for road surfaces with adequate traction. I don't agree that airing down reduces tire wear, in fact, I believe it's harder on the tires but is better overall for the chassis and ride quality, so I'd recommend doing it anyway. Lastly, engaging 4wd does not reduce tire wear, it increases it because in 4wd the front axle is locked with the rear and this causes wear on the front tires in radius turns. 4wd may help reduce wheel slip in tractionless situations, which is why anyone would recommend to engage it. But not for the purposes of reducing tire wear, otherwise 2wd when there is adequate traction.

Last edited by jk_sea; Mar 25, 2015 at 02:14 PM.
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