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Discussion Starter · #1 ·
To preface this a bit, I don't mean long range or the like.

I'm going to be towing with the WK2 (21 Overland with towing pkg) for the first time this weekend. In this case, it's a boom lift that I'll be positioning in a couple places through the front yard. In past years when I've used either my old Bravada or more recently my brother's truck, we occasionally had trouble spinning and trenched the yard a bit. So I was thinking that if I dropped into 4Low to lower the gear ratio, there'd be a little less chance of that. Question is, is the gearing in 4Low ok for the extra load like that?

Side question, would using Sand or Mud mode further decrease the risk of trenching it? I'm a little less certain about Mud since that defaults to OR1 ride height.
 

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I don't see how using 4-low would be worse than 4-high, I would assume it's actually better and puts significantly less stress on your transmission. It will also lock your front and rear "axles" (I know they're not axles, I'm not sure the right term to use) together for significantly better traction. Just make sure you take it out of 4-low any time you're on solid, hard, and dry terrain like asphalt. Should be fine in grass, dirt, mud, etc. Also it goes without saying, keep your speed well below 25 mph.

As far as which mode to use, probably I would just leave it in Auto. The Sand and mud modes are really optimized for a standard vehicle load, they're not likely to work right while towing a several-ton load, I don't think. You could try, it probably won't hurt anything, but personally I think I'd just leave it in Auto.

One other trick, throw the shifter into manual mode, and do manual shifts between 1st and 2nd gear as needed, depending on your speed. 3rd gear and above should not be necessary at all for what you're doing, but in Automatic (Drive) mode the transmission will want to use 3rd and 4th gears, which kind of negates the point of using 4-low. When I go offroading, I exclusively only use 1st to 3rd gears (in my 8-speed wk2), there is never a need to use 4th gear, but when I leave the shifter in Drive, the transmission naturally wants to go into 4th gear (and sometimes even 5th gear) above about 6mph, which is not ideal.

Have a Plan B in case you start spinning wheels and digging holes. Have some recovery boards or some other way of getting yourself out, before you begin. Not fun to go find that stuff later after you're already stuck.
 

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To preface this a bit, I don't mean long range or the like.

I'm going to be towing with the WK2 (21 Overland with towing pkg) for the first time this weekend. In this case, it's a boom lift that I'll be positioning in a couple places through the front yard. In past years when I've used either my old Bravada or more recently my brother's truck, we occasionally had trouble spinning and trenched the yard a bit. So I was thinking that if I dropped into 4Low to lower the gear ratio, there'd be a little less chance of that. Question is, is the gearing in 4Low ok for the extra load like that?

Side question, would using Sand or Mud mode further decrease the risk of trenching it? I'm a little less certain about Mud since that defaults to OR1 ride height.
Tough call because 4low really isn't meant for any type of towing. If you try it, don't go above 15mph. (25mph limit is for standard load). Correct me if I'm wrong...but when in 4low, doesn't it have to be in rock mode? If not...try mud or sand mode. Reason why: leaving it in auto would let the tires dig holes prior to the system reactivating to the changes in terrain that you're on. Nornally it's not an issue but being in that terrain while trying to tow could cause an issue. Hope I made sense there lol.
 

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Discussion Starter · #4 ·
Tough call because 4low really isn't meant for any type of towing. If you try it, don't go above 15mph. (25mph limit is for standard load).
In this case, we'd be talking crawl speeds (like 2-3 mph while moving from one point to the next). I was just thinking of dropping in to 4Low when I was in the yard to help prevent spinning as much as I can.
 

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Just want to share my newbie experience, 4 months in with my wk2. I used 4lo in my yard parking my boat in a tempo. When needing finesse it was a lot easier, not jumpy or jolting.
Same experience pulling the boat out of water on a back country makeshift launch on an incline was super helpful as.
 

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At the very low speed you'd be maneuvering the lift on your lawn, I don't see and issue. But I wouldn't recommend it for "on the road". 4-low really is for "crawling".
 

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Side question, would using Sand or Mud mode further decrease the risk of trenching it? I'm a little less certain about Mud since that defaults to OR1 ride height.
Sand and Mud modes disables the traction control, which would be great for creating trenches.

IF you have the Quadra Lift suspension:
Sand mode retains Normal Ride Height,
Mud Mode raises the Jeep to the Off-Road 1 position

Snow Mode would keep the tires from spinning. BUT, Snow Mode robs all power from the vehicle if it senses any tire slip.

I believe that Auto Mode would be your best option.
 

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As I @DoMyOwnRacin mentioned above the mode select will disable some of traction controls and put your QL in different ride height’s. You don’t have front lockers and may not even have the rear ELSD. If you get the little idiot light on the dash when it’s engaged into 4 lol than you have it. No big deal, if you do or not 4lo will work fine if it’s jaunt’s round the yard and leaving it in auto to allow the traction control system to do it’s job. And the WK2’s are a completely different animal than previous models when it comes to the drivetrain. I always here, “Be careful in 4lo on dry ground”, in an older model with a straight axle, or a different traction distribution system, that holds some weight, but with today’s WK2’s the computer takes care of any “binding” that most people are referring to when they mention that. 4lo can be utilized on dry surfaces (sand is dry) under instances of traction loss, like climbing Lion’s back in Moab etc....It will shoot the rpms up because it changes the final drive ratio and that’s about the only reason today that you wouldn’t use it as a driving speed option.

I couldn’t get my Power Wagon out the driveway in 4lo without enough snow on the road to allow slippage to occur, If you want to experience binding try it with a 21ft truck on 37’s with 4:56’s, that’ll rattle your teeth out, lol.
 

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At least some of the modes let you start in 2nd gear, which will be a big help in avoiding wheelspin.
Pretty sure snow mode does that, not sure about the others.
Or, once in drive, hit the upshift paddle before trying to move. That will put it into 2nd.
 
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I'm reading a lot of misunderstanding about what the terrain modes actually do. I don't have the references, but I researched this some years ago and it takes some digging to actually get the answers. For my 2016 WK2 Limited with QuadraDrive and no air suspension, I have five settings: Auto, Snow, Sand, Mud, Rock. Going through the list below, you can see that the differences in the terrain modes can be subtle. For the most part, I think having the terrain modes is marketing. People see the knob, and think that it's a serious 4x4 system. I know people who have a Toyota Highlander with a terrain select knob and no idea what it is actually doing, but they think it has a knob so it must be good and doing something important.

Also, switching into 4x4 Low locks the CENTER differential. On the WK2, there are no lockers in the front or rear differential.

For each of these terrain settings, there are other things that are affected like the ride height on the air suspension, if you have it.

Auto-
- Sets torque bias and distribution to 40/60 front/rear
- Baseline ESC controls

Snow -
- Sets torque bias and distribution to 50/50 front/rear
- Sets ESC as MORE aggressive to control wheel spin
- Starts in 2nd gear

Sand -
- Sets torque bias and distribution to 50/50 front/rear
- Sets ESC as MORE aggressive to control wheel spin

Mud -
- Sets torque bias and distribution to 50/50 front/rear
- Sets ESC as LESS aggressive to allow wheel spin

Rock -
- Sets torque bias and distribution to 50/50 front/rear
- Sets ESC as MORE aggressive to control wheel spin
- Allows Hill Descent Control to be used, which uses the brakes to control the speed between 1 - 5 MPH, the paddle shifters are used to change the speed setpoint
- Only available in 4x4 Low

There are likely going to be some other aspects of the vehicle's control system that are affected by these modes, of course, but these are the major points.
 

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Also, switching into 4x4 Low locks the CENTER differential. On the WK2, there are no lockers in the front or rear differential.
Just to note, some models have Electronic Limited Slip Rear Differentials.

The front differentials on all models are conventional, open (non-locking) differentials.
 

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Just to note, some models have Electronic Limited Slip Rear Differentials.

The front differentials on all models are conventional, open (non-locking) differentials.
The limited slip function of the ELSD is not a locker, and the ESC cannot/does not lock the rear differential based on the terrain selection or sport mode. But I get what you are saying, and it's a good note.
 

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Going into 4LOW will put you in Part-Time 4WD, or 4x4. The front and rear axles will turn at the same speed. You can not use this mode on high traction surfaces, it has to be a low traction surface that allows the tires to slip. Because as you turn, the wheels will slip on the surface.

So, you want to avoid trenching the yard. So keep in mind how 4LOW works. the low gearing might avoid wheel spinning and thus the trenching. At the same time, if you turn, wheels are going to slip and the slipping could do yard damage and it might get trenching started.
 

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Mongo, JGC is full time 4WD, regardless. Perhaps you mention something else by "Part Time 4WD"?
 

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Jim, I know you know this, but this is written with more detail for those who don't, for you, the response is that third bullet for Full-time 4WD. I went and typed this up, but there are blogs about this topic already out there I could have just linked to. When a car is called AWD, 4WD, or 4x4, those are mostly marketing with no fixed standard about what is AWD or 4x4. People buying a jeep don't want to see AWD on the back, like it's a sedan, and people going for a cheaper on the road driver can be talked into paying for AWD easier than 4x4. That's what I've been able to collect about it.

Part-time and Full-time 4WD, however, are different. And the difference is whether it has a center differential or just a transfer case.

Full-time 4WD
  • Has a center differential paired with the transfer case that is sending power/torque to the front and rear axles.
  • Can be driven in four wheel drive 'full-time', including on hard surfaces. With a center differential, the front and rear 'axles' can have differing average rotational speeds when the vehicle is turning, and you won't have gear binding or tire slippage.
  • The center differential may be able to be LOCKED, which while it is locked essentially makes it:

Part-time 4WD
  • Has only a transfer case that is sending power/torque to the front and rear 'axles'.
  • Can be driven in four wheel drive ONLY 'part-time', when on soft surfaces or when driving slowly, like rock crawling. Without a center differential, the front and rear 'axles' have the same average rotational speeds when the vehicle is turning, and you will have gear binding or tire slippage. This is because on a turn, the rear tires take a tighter turn than the front tires.
 

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This is actually why I picked the Wk2 over the 4Runner. When I was shopping, the 4Runner didn't have a center differential unless you went for the highest trim level, and I wasn't going to pay that much just for something which I think every 4WD vehicle should have. Not having a center differential that can be unlocked is just cheap. It only makes sense on vehicles which would never be on the road, like an ATV.
 

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JGC center differential exists and is "open", so it fits the definition of Full Time 4WD/AWD as you noted, DriveAbout. That's why it's so flexible in various conditions...it can be a nice, gentle "AWD" type experience on the highway while offering advanced tricks and capabilities in more difficult situations with QT-II/QD--II. I really appreciate how it was engineered in that respect.
 
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