4H or 2H as deffault for offroading?

Wojo

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I read that using 4H on the pavement can damage your transmission so the question is do I have to keep switching between 2H and 4H when going between trails and hard packed dirt roads or can I just leave it in 4H?
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I'm a noobie, so I hope someone confirms (or denies) my advice. 4H would be ok on hard packed dirt, especially for low speeds, because there would enough slippage of dirt and tire rubber to avoid gear binding from the wheels rotating a relatively the same speed. Dry pavement will 'grip' the tire rubber and the slippage may occur at gears (aka wheel hop, binding, etc.) I don't think this will happen on packed dirt.
 

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4H is perfectly fine for a default for off roading. If you have a Rubicon I don't recommend running around with the dif locks on. Past that no reason not to.

Not that is translates directly to a JL but my old Cherokee is only 4H or 4L. No 2 wheel drive option, and I can assure you that at least 200k of the 270k mile on it were on the road.
 

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One additional note. All JL's, even with 4x4 engaged have some slip in both front and rear differentials. This is specifically so the four wheel drive can be engaged while on firm surfaces as well as for driveability while off road. The only way to actually lock all 4 wheels is with a electric differential lock like the Rubicon or swapping out the axles would something like an ARB with airlockers. (Most run between 8-16k)
 
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One additional note. All JL's, even with 4x4 engaged have some slip in both front and rear differentials. This is specifically so the four wheel drive can be engaged while on firm surfaces as well as for driveability while off road. The only way to actually lock all 4 wheels is with a electric differential lock like the Rubicon or swapping out the axles would something like an ARB with airlockers. (Most run between 8-16k)
Cool, thanks for the info! I do have a Rubicon. Another question, can I shift from 4H to 4L on the fly or do I need to stop and shift to neutral first?
 

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Cool, thanks for the info! I do have a Rubicon. Another question, can I shift from 4H to 4L on the fly or do I need to stop and shift to neutral first?
Shift on the fly. While rolling 2-3 mph pop it in neutral. After your neutral you can shift from 4 high to 4 Low. I actually recommend not trying to shift into 4 low unless it's rolling.
 
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Shift on the fly. While rolling 2-3 mph pop it in neutral. After your neutral you can shift from 4 high to 4 Low. I actually recommend not trying to shift into 4 low unless it's rolling.
Btw, awesome mojito, everytime I see a picture of a mojito Rubi I wish I had the patience to wait just a little longer before ordering mine! So, what if I am stuck in mud, too late to put it in 4L then? Also do you think lockers will help with mud or are they just for rock crawling?
 

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Btw, awesome mojito, everytime I see a picture of a mojito Rubi I wish I had the patience to wait just a little longer before ordering mine! So, what if I am stuck in mud, too late to put it in 4L then? Also do you think lockers will help with mud or are they just for rock crawling?
It's not to late to put it into 4L, however most mud boggers prefer the higher wheel speed of 4H. The extra spin allows some of the mud to fly out of the tread and allow a fresh bite into the mud. I prefer this method as it seems to work best for me. Without the tazor programmer you can't engage the lockers in 4H.

If you have mud on your mind, get a winch. It will save you and others. I've only used it to get me out twice, but it's allowed me to easily save many others.
 

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The JL has a FAD system, and typically those need a slight bit of axle rotation to allow the collar to engage the splines. So, if you're totally stuck in 2-wheel drive and not moving, it's possible that you may not be able to shift to 4-wheel drive at that point.

Whether to use high or low range depends on the specific conditions you're in. Deep mud? I'd go low range to avoid over heating the trans. Pretty much anytime I'll be putting a lot of strain on the driveline I go with low range. The only time I ever use high range is to get up my gravel driveway with a trailer hooked on (10% grade) or if it snows in the winter.
 

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My transfer case will not slip into neutral without the trans being in neutral as well (automatic). It will make bad noises if you are rolling much over 1 mph and slipping it into 4L. When I'm on the trails I'm in 4L, but these are not high speed trails. If i'm going between trails on gravel roads I just go back to 2H, but 4H is ok. In deep mud (which I despise) you really need wheel speed to clear out the tire treads so 4H is the best option. In slippery conditions, lockers may be more of a hindrance since slipping tires have no traction. The non spinning tire acts like a rudder in an open diff more or less keeping you from doing 360's. LSD's suck in icy condition for example.
 
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Shift on the fly. While rolling 2-3 mph pop it in neutral. After your neutral you can shift from 4 high to 4 Low. I actually recommend not trying to shift into 4 low unless it's rolling.
Shift into neutral before shifting into 4L on the main Auto transmission (drive to neutral) or on the 4WD stick shift (4h to neutral)?
 
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My transfer case will not slip into neutral without the trans being in neutral as well (automatic). It will make bad noises if you are rolling much over 1 mph and slipping it into 4L. When I'm on the trails I'm in 4L, but these are not high speed trails. If i'm going between trails on gravel roads I just go back to 2H, but 4H is ok. In deep mud (which I despise) you really need wheel speed to clear out the tire treads so 4H is the best option. In slippery conditions, lockers may be more of a hindrance since slipping tires have no traction. The non spinning tire acts like a rudder in an open diff more or less keeping you from doing 360's. LSD's suck in icy condition for example.
Thank you for your reply! So just want to make sure I am getting this right because I have an auto transmission too. When going from 4h to 4l, first I should shift the from drive to neutral then also shift the 4wd shifter into neutral too followed by shifting it into 4l then shift back into drive again? All while rolling at around 1mph?
 

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Thank you for your reply! So just want to make sure I am getting this right because I have an auto transmission too. When going from 4h to 4l, first I should shift the from drive to neutral then also shift the 4wd shifter into neutral too followed by shifting it into 4l then shift back into drive again? All while rolling at around 1mph?
Yes, only you don't really need to be rolling around necessarily. Just put the trans into neutral then pull the transfer case to the right and down. Once in 4L go back to drive. My transfer case will sometimes jump back into neutral like it wasn't "locked" in, I just firmly put it back into 4L and I'm good until I switch it out of 4L. One of those idiosyncrasies with my Jeep.
 

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Many times in CO you'll be on dirt/rocky trails that don't require 4wd but you're at a steady incline.

My curiosity was around if it's better to leave it in 4-H to distribute some of the load to the front axle which would likely take a little load off the rear axle. Many times if it's super steep I'll use 4-L for the gearing anyways.
 
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