For owners ... how is the awd??

[zdr]

4WD Auto is not AWD. Do not equate the two. They operate differently.

AWD distributes power to all 4 wheels even if they are spinning at different speeds (which happens in every turn or curve in the road). AWD is superior to 4WD in slick on-road conditions.

4WD Auto is 2WD until the rear tires slip, then 4WD HI is quickly and seamlessly engaged. It returns to 2WD as soon as the rear tires stop slipping. 4WD Auto exists to mitigate how 4WD HI can cause the driver to lose control in higher speed turns & curves in slick on-road conditions and skid off the road. 4WD is far superior to AWD in off-road conditions, which is why the JL doesn't have AWD.

Sounds like my old 2001 Grand Cherokee with Quadra-Trac. It was a beast driving in the snow. Could drive close to speed limits in heavy snow.

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[GATORB8]

 

[thegame81]

Not that bad, and a easy job.

Thanks Mike

 

[MonLee]

Snow driving is more about the tire than it is drivetrain. Ive only had my wrangler for 2 months and ive barely used the 4auto, im extremely impressed with how good the traction is even in the rain, in 2wd so i haven't felt like i needed it much. The tires that came on my sport s are incredible.

Basically 4wd auto is snow mode/difficult left turn in the rain mode in my mind currently.

 

[N75]

4WD Auto is not AWD. Do not equate the two. They operate differently.

AWD distributes power to all 4 wheels even if they are spinning at different speeds (which happens in every turn or curve in the road). AWD is superior to 4WD in slick on-road conditions.

4WD Auto is 2WD until the rear tires slip, then 4WD HI is quickly and seamlessly engaged. It returns to 2WD as soon as the rear tires stop slipping. 4WD Auto exists to mitigate how 4WD HI can cause the driver to lose control in higher speed turns & curves in slick on-road conditions and skid off the road. 4WD is far superior to AWD in off-road conditions, which is why the JL doesn't have AWD.

Not all AWD is as you explain it. Haldex based systems (transverse VW/Audi, Mini, Volvo) are front wheel drive based with a rear prop shaft that always spins (some new Audi's mechanically decouple for fuel savings but that's not important). The Haldex "center" coupler is really bolted to or part of the rear diff housing, and is fully decoupled when the front wheels aren't slipping. So your Audi TT or Volvo S60 is 100% front wheel drive until either a) the ECU detects front wheels spinning faster than the rear, accounting for differing wheel speeds in turns using wheel speed sensors or b) you hammer the throttle and the ECU locks up the Haldex to provide traction even if wheel spin hasn't occurred.

The reason these systems don't bind is because they work much like limited slip diff (though electronically controlled rather than purely mechanical). If you go around a sharp turn and hit dry pavement with good traction, the clutch pack allows center coupling slippage which prevents binding and wheel hop.

Other AWD layouts include typical Benz with three open diffs plus electronic traction control, longitudinal Audi with a Torsen center diff (I personally love these for snow), BMW longitudinal xDrive which runs both front and rear outputs through a wet clutch system so it can throw all power either direction, Subaru (manual transmission version) which is a viscous coupling that reacts mechanically to slippage, and now various e-AWD systems - check out a Ford Maverick/Fusion for a weird layout or Volvo T8 with front gas and rear electric, or Tesla dual motor (one per axle).

I refer to Jeep's auto 4-hi as backwards Haldex because instead of being FWD and engaging the rear up to 50/50 split as needed while still allowing slippage, Jeep is RWD but can engage the front. Jeep also allows you to "lock" the center coupling which isn't a true mechanical lock like part time systems, but simply the hydraulic control of the clutch pack stays fully engaged regardless of wheel speed differences mimicking traditional 4WD.

 

[GATORB8]

I refer to Jeep's auto 4-hi as backwards Haldex because instead of being FWD and engaging the rear up to 50/50 split as needed while still allowing slippage, Jeep is RWD but can engage the front. Jeep also allows you to "lock" the center coupling which isn't a true mechanical lock like part time systems, but simply the hydraulic control of the clutch pack stays fully engaged regardless of wheel speed differences mimicking traditional 4WD.

Have you found documentation of variable wet clutch engagement in the MP3022? Or any actual specifications for that matter.

I've done some searching and the best thing I've found so far is a post on a Jeep Liberty forum of all places.

 

[Reinen]

Not all AWD is as you explain it.

Yup, I was keeping it short & basic. Didn't seem like the OP was interested in details.

 

[supermike]

We had some heavy rain this morning, did some spirited driving and sharing the experience.

It is very much a RWD, power won’t sent to front axle until slip is detected. I was intentionally given heavy throttle input during turns, the system is kind of slow to react and will kick in half way to catch you off guard, but I know it’s not a AWD or RWD and I’m not supposed to drive like that, just trying to find how it will behave. what I’m trying to say is ASSUMING 4H auto=AWD is DANGEROUS!

 

[thegame81]

We had some heavy rain this morning, did some spirited driving and sharing the experience.

It is very much a RWD, power won’t sent to front axle until slip is detected. I was intentionally given heavy throttle input during turns, the system is kind of slow to react and will kick in half way to catch you off guard, but I know it’s not a AWD or RWD and I’m not supposed to drive like that, just trying to find how it will behave. what I’m trying to say is ASSUMING 4H auto=AWD is DANGEROUS!

Hmm yea that's basically what my friend was saying. It doesn't do a good job of planting the jeep to the slippery road. That kind of sucks lol I was hoping it would be great with the auto 4 in slippery cold situations.

 

[supermike]

Hmm yea that's basically what my friend was saying. It doesn't do a good job of planting the jeep to the slippery road. That kind of sucks lol I was hoping it would be great with the auto 4 in slippery cold situations.

emmmmm…it’s working just fine if driving gently. It was not supposed to work like Subaru or Audi Quattro on road and definitely not under 392 power.

 

[thegame81]

emmmmm…it’s working just fine if driving gently. It was not supposed to work like Subaru or Audi Quattro on road and definitely not under 392 power.

Yea I totally agree. The hooligan in me was hoping it would be a jeep/GTR bastard child

 

[supermike]

Yea I totally agree. The hooligan in me was hoping it would be a jeep/GTR bastard child

we all wish that. It’s like an Ultimate muscle car. Adequate power, no handling no brake, excitement level is through the roof…

 

[thegame81]

Hope I'm not coming across bad. I'm just kind of excited to be getting it soon. I guess no vehicle is perfect for every situation though.

So I take it of its a light snow with slippery conditions a grand cherokee with awd would be better to drive home from work.

If it's a major snowstorm where you have over a foot of snow may be better to be in the wrangler than the cherokee.

Can't wait to get my 392 still!

 

[Reinen]

Hope I'm not coming across bad. I'm just kind of excited to be getting it soon. I guess no vehicle is perfect for every situation though.

So I take it of its a light snow with slippery conditions a grand cherokee with awd would be better to drive home from work.

If it's a major snowstorm where you have over a foot of snow may be better to be in the wrangler than the cherokee.

Can't wait to get my 392 still!

You got it. Light slippery snow, AWD. Major snowstorm, Jeep.

I'll take that one step further. I've driven a Jeep in snow so deep that I had a bow wake of snow rolling off the fenders. If I went fast enough (and I could) it pushed the snow over the hood rolling it off the sides of the windshield. Which was both awesome and extremely unnerving. You know you're still moving forward but you can't see a damn thing besides snow moving across the glass.

 

[thegame81]

You got it. Light slippery snow, AWD. Major snowstorm, Jeep.

I'll take that one step further. I've driven a Jeep in snow so deep that I had a bow wake of snow rolling off the fenders. If I went fast enough (and I could) it pushed the snow over the hood rolling it off the sides of the windshield. Which was both awesome and extremely unnerving. You know you're still moving forward but you can't see a damn thing besides snow moving across the glass.

Lol damn that sounds crazy

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