Full-time 4WD issues?

[NeoLeo]

Hi Friends - In my 2012 JKU, the factory manual warns to not drive in 4Hi on dry road conditions for extended periods. Since the 392 is full-time 4WD, is that going to be an issue to drive on non-slippery dry roads?

THanks!

 

[Viking Jeeper]

Take a look at the 392 performance supplement, easily found on the World Wide Web.

 

[veddersbetter]

Hi Friends - In my 2012 JKU, the factory manual warns to not drive in 4Hi on dry road conditions for extended periods. Since the 392 is full-time 4WD, is that going to be an issue to drive on non-slippery dry roads?

THanks!

Not at all. Quite a few differences including CV joints. No binding at all.

 

[YukonCornelius]

Welcome, @NeoLeo

Shouldn't be a concern... FT-4WD or AWD are a little different than 4Hi - which the 392 does also have, in which case you are correct - 4Hi shouldn't be driven much on dry pavement, but you're fine with the FT 4WD. It's what it's designed for.

 

[Turboencabulator]

Hi Friends - In my 2012 JKU, the factory manual warns to not drive in 4Hi on dry road conditions for extended periods. Since the 392 is full-time 4WD, is that going to be an issue to drive on non-slippery dry roads?

THanks!

I think your confusing 4WD High Auto and 4WD High Part Time (something I did initially):

4WD High AUTO: This is the default mode in the 392 and is for normal street and highway driving. This range always sends power to the rear wheels. However it will send power to the front wheels automatically when the vehicle senses a loss of traction to optimize traction as needed.

4WD High Part-Time: This mode forces the front and rear axels to turn at the same speed. This range provides additional traction for loose, slippery surfaces only. You can engage the Front and Rear Lockers that will force all wheels to spin a the same speed effectively delivering 25% of the power to each wheel.

 

[NeoLeo]

Kind thanks, Friends! This is a great forum! About to order one but wanted to understand this part first. Nothing makes sense about this ride… which is it’s captivating! Best!

 

[Yaak392]

I think your confusing 4WD High Auto and 4WD High Part Time (something I did initially):

4WD High AUTO: This is the default mode in the 392 and is for normal street and highway driving. This range always sends power to the rear wheels. However it will send power to the front wheels automatically when the vehicle senses a loss of traction to optimize traction as needed.

4WD High Part-Time: This mode forces the front and rear axels to turn at the same speed. This range provides additional traction for loose, slippery surfaces only. You can engage the Front and Rear Lockers that will force all wheels to spin a the same speed effectively delivering 25% of the power to each wheel.

Hate to dispute, but if you read the aforementioned supplement it front first then front and rear as needed

 

[Yaak392]

Also, I don't want to create an argument. I'm just trying to help new owners know what they are getting.

 

[Proptrash]

Hate to dispute, but if you read the aforementioned supplement it front first then front and rear as needed

Hate to dispute, but if you read the aforementioned supplement it front first then front and rear as needed

 

[Turboencabulator]

Hate to dispute, but if you read the aforementioned supplement it front first then front and rear as needed

You are correct that on pg. 13 of the 392 Performance Guide it does say:

4H AUTO
Four-Wheel Drive Auto High Range — This range is for normal street and highway driving on dry, hard surfaced roads. This range sends power to the front wheels. The four-wheel drive system will be automatically engaged when the vehicle senses a loss of traction. Additional traction for varying road conditions.

However, when it says: "This range sends power to the front wheels" that is not the same thing as saying it sends power to the "front first then front and rear as needed". The MP3022 transfer case uses an electronically controlled wet clutch to provide between 50/50 front/rear split up to 100% rear drive based on bias. I don't believe it was designed to ever go into 100% front wheel drive. Here is a video from MOPAR explaining the 4H AUTO in more detail:

So I stand by my original statement: 4H Auto: This range always sends power to the rear wheels. However it will send power to the front wheels automatically when the vehicle senses a loss of traction to optimize traction as needed.

 

[Turboencabulator]

Also, I don't want to create an argument. I'm just trying to help new owners know what they are getting.

I appreciate your post, and I hope I can add to the discussion with what I have learned so far about this monster truck, no argument on my part. It is important that new owners know what they are getting into and I like all the good info I get on this forum!

 

[Proptrash]

You are correct that on pg. 13 of the 392 Performance Guide it does say:

4H AUTO
Four-Wheel Drive Auto High Range — This range is for normal street and highway driving on dry, hard surfaced roads. This range sends power to the front wheels. The four-wheel drive system will be automatically engaged when the vehicle senses a loss of traction. Additional traction for varying road conditions.

However, when it says: "This range sends power to the front wheels" that is not the same thing as saying it sends power to the "front first then front and rear as needed". The MP3022 transfer case uses an electronically controlled wet clutch to provide between 50/50 front/rear split up to 100% rear drive based on bias. I don't believe it was designed to ever go into 100% front wheel drive. Here is a video from MOPAR explaining the 4H AUTO in more detail:

So I stand by my original statement: 4H Auto: This range always sends power to the rear wheels. However it will send power to the front wheels automatically when the vehicle senses a loss of traction to optimize traction as needed.

Agree

 

[Jeepstin392]

Hate to dispute, but if you read the aforementioned supplement it front first then front and rear as needed

I read that as well. It’s written incorrectly And easily misinterprete.
Go anywhere traction is lacking, blip the skinny pedal, and you’ll notice the rear spin a bit before the front engages. Saw another post you’re tagged in which does a good job explaining the detail.

 

[BenLandry]

I posted this a couple of weeks ago. On the right side of the pic is my 392 coming at you in 4auto, normal driving mode. the rear wheels start to spin but if you look close you can see where the front grab traction. Left side of pic is forced RWD.