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Or does the load leveling make the vehicle a virtual lever arm? My guess, the WDH would be far more effective....
Load leveling does zero to re-balance between the axles. Only a WDH can do that and it uses leverage to accomplish it as was noted by jfinca.
 

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That makes no sense to me, you change spring rate, spring force and ride height between the axles, but that does nothing to re-balance between the axles? It's matter of does it re-balance for the better or worse.... ...so I go look it up, and see a test where they weigh each wheel for either Load Leveling and WDH, sure enough, load leveling causes the rear axle to take more of the load, and front and trailer axles to take less, you know what the results for the WDH was. Thing to keep in mind the differences were minor, but it was moving in the wrong direction, not better....
 

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The springs support weight, but they do not shift it. Leverage is required to do that...the laws of physics. :) :D
 

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The springs support weight, but they do not shift it. Leverage is required to do that...the laws of physics. :) :D
Ummm, wheelbase is a lever arm, that is why wheelbase is a huge factor in chassis and suspension dynamics.... ...the whole length of the vehicle is a lever arm, if you've ever calculated Center of Gravity of an aircraft you'd see that.... ....if there is no leverage for load leveling, then load level would not change the angles of the levers of the vehicle and towed load, would it?... ...you're not suggesting that changing load, spring rates and damping on one axle has no effect on the other axle, cause that is well proven concept of suspension design and modification.... ...nor would the front axle go down when load leveling raised the rear axle if the wheelbase was not a lever arm...

The test weighing each wheel with load leveling and wdh proves the laws of physics, you change spring rate, spring force and ride height at one axle it changes the other axles, including the weight (or load) at each axle changed using load leveling..... ...search youtube for a video of it, big white truck with flatbed trailer and observe the laws of physics yourself, they prove load leveling redistributes weight......

The thing is with load leveling, it shifted more weight to the rear axle of the Tow vehicle and away from the other axles, than there was before, not away from the rear axle and more toward the other axles, like WDH does.....

It also showed that load leveling made a very small change in that weight distribution, although for the worse, so the stipulations on Towing for tongue weights and to use WDH if you exceed a certain tongue weight sorta indicates to me, the load leveling might make the dynamics a little worse but still well within the capabilities of the vehicle, i.e. it is for head lamp aiming and comfort as well as looks.... ....But it is no substitute for a WDH when one is required, I've never claimed that, but what I didn't realize, if anything Load Leveling makes load distribution slightly worse while towing, a heavy load in the cargo area, it probably makes it better....

We are violently agree on the end result, except you can add to "Load Leveling is just for looks, if anything it redistributing the weight slightly worse than what you want"... I'd only add, head lamp aim is more than just a convenience and being able to see over the hood better is a convenience most would be grateful....
 

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Another way to look at this..... ...since I finally understand the physics behind the WDH....
The tow vehicle and towed load are two separate levers that create a torque on each other, the point of rotation for the torque is the ball hitch/tongue connection..... ....you apply an opposite torque at that point you re-balance the levers....

The WDH is a big spring that applies a torque in the opposite direction at that point, ball hitch/tongue, and re-balances the levers....

The suspension is reacting to re-balance the levers, otherwise the ball hitch would go much lower than it already does for the tongue weight.....

Load Leveling re-balances the levers, the levers do move and change angle, but since its much closer to the fulcrum of one lever, it is apply the torque between the levers more toward the fulcrum than the end of the lever, if anything the weight distribution gets worse....
 

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Ummm, wheelbase is a lever arm, that is why wheelbase is a huge factor in chassis and suspension dynamics.... ...the whole length of the vehicle is a lever arm, if you've ever calculated Center of Gravity of an aircraft you'd see that.... ....if there is no leverage for load leveling, then load level would not change the angles of the levers of the vehicle and towed load, would it?...
Changing the springs doesn't alter the "leverage" that the wheelbase already provides. The only way to shift tongue weight forward is with a WDH.
 

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Changing the springs doesn't alter the "leverage" that the wheelbase already provides. The only way to shift tongue weight forward is with a WDH.
Watch the video, you can post there telling them they are violating the laws of physics....

If what you're saying is true, the weights at every wheel would NOT change as they increased the spring force at the rear wheels, but the weight on every wheel changed, the load was redistributed, but slightly worse, not better....

A WDH doesn't alter "leverage" either, it simply applies a counteracting torque at the ball hitch/tongue to both levers....

Changing force doesn't alter a lever or the mechanical advantage of a lever, it alters the resulting moment or torque. Unless you apply the force directly to the fulcrum, then there is no leverage. More force on a lever produces a resulting force on/from the lever proportional to the mechanical advantage of the lever. So it is also important where you apply the force on the lever.
Do you really think applying more force to a wrench doesn't change the ft-lbs the wrench applies.
If you're going to argue that the rear axle is the fulcrum, than the front of the vehicle would never come down, you would apply zero torque to the lever if you apply it directly to the fulcrum, the fulcrum would move but the lever would never turn....

The WDH, by counteracting the torque between the two levers at the end of the levers, it does the same as virtually shifting the tongue weight forwards....

The Load Level applies a torque near the fulcrum of the lever in the front, it doesn't have near the leverage and when all is said and down, it moves the fulcrum as well as torques the lever and the weight distribution ends up moving rearwards...

Changing spring rates on the vehicle is going to create torque on the lever as well, but its net result in redistributing the load will be negative, despite moving the arms, its virtually move the tongue weight rearward slightly..... ...that is with a lever connected to the hitch... ...if you had a heavy load in the rear cargo area with no trailer, the net result would likely be to redistribute the weight more forward....
 

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More concise...
A WDH applies a torque at the ends of the 2 levers, right where they join, which is the most advantageous....
Load Leveling applies a force near the fulcrum of one of the levers, on a lever that has a shifting fulcrum, not nearly as advantageous...

...I don't know, but I suspect in that video as the suspension force changes and moves the lever of the front vehicle, the fulcrum shifts more rearward to equal the rear axle and then it just raises the fulcrum... ...that is why they never fully got the vehicle level and got the result of the tongue weight virtually shifting rearward a bit...
 

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I have a 2015 JGC Larado AWD. When I was evaluating vehicles, one of the reasons I went with Jeep was the 6200 towing capacity for the gas 6 cylinder. I almost did not buy the car because the salesperson said that was not correct. I showed him the literature and made him call Chrysler to get the correct information. I did get the full tow plackage on the GJC and I also use a WDH. I tow a 5600 pound (loaded) travel trailer. The JGC does a great job of towing. I monitor engine and transmission temperatures and the towing package adequately keeps these in acceptable ranges.

IMHO,the JGC is the best 6 cylinder towing vehicle on the market.
 

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Yea, there was another thread on the loose use of the word tow and other terms in various documents and how it creates a lot of confusion... ....I just checked my 2011 owners manual quick and it wasn't clear there is a difference in tow capacity for tow package equipped and non-equipped WK2's.... ...it simply has the table that has often been listed on this site.... ...and it has changed for the V6 in later years.... ...I keep reading on this site that without a tow package, towing capacity is 3500lbs.... ...I have to look closer at the O.M.....
 

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Yep, and I checked it only 5 minutes ago and read right past that scanning for a table, I saw "Your vehicle may be factory equipped for safe towing of trailers weighing over 3,500 lbs..." I should have finished the sentence that does end with "....with the optional Trailer Tow Prep Package. See your authorized dealer for package content."

So that does discount the table on the next page listing 5,000lbs, 7,400lbs and 7,200lbs towing capacity.... ...it could be better worded, I can see a lot of morons totally screwing that up... ...although the morons never take the O.M. out of the shrink wrap, so can you really blame them?
 

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So that does discount the table on the next page listing 5,000lbs, 7,400lbs and 7,200lbs towing capacity.
Yes, it does. The table is for an "appropriately equipped" JGC. But as you say, it's been a moving target for what is the acceptable limit for a non-Factory Tow JGC by specification. Some years it was 3500. Some it was 5000. It keeps bouncing around. Bottom line for me is that if one is going to do "real towing" beyond something small...have the Factory Tow option on it when you buy it. If it needs bakes to comply with the law (which in most states/provinces in NA 3000 lbs), get a JGC with the Factory Tow option. Can you get away with other scenarios? Likely. But it only takes one incident to get someone hurt or worse.
 

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I was more complaining about the roundabout way of stating the non-tow package equipped limit.... ...i.e. it should simply state Tow Capacity is 3500 lbs... ...like it should be another entry on the table for non tow package equipped, not saying "you may", etc...

That might have something to do with the capacity jumping up and down different years, its really not cut and dry....

What does the Tow Package include again? I was searching for this earlier, and didn't find it easily....
  • Load Leveling Shocks and rear springs (If you don't have QL, that will load level)
  • Full Sized Spare
  • HD Radiator
  • HD Fan
  • 220 Amp Alternator
  • Class IV Hitch
  • Tow Wiring with Connector for Electric Brake (That is in all WK2's, except one M/Y regardless if it has the TOW Pkg or not)
As discussed, the load leveling is not helping control the towed trailer, its just leveling the vehicle..... the rest of the equipment doesn't do anything to safely control the load either... ...I'm not dismissing those things in the package, depending on what you're towing you will need them, some might be situational, that you don't need it for a certain situation, i.e. have a trailer that doesn't need to electrically powered other than signal lights, etc...

I looked at information for fans, there isn't enough to tell, the HD fan has different wiring, so it could be very difficult/expensive to change the wiring and to get it to work in replace of the SD fan... ...Load Leveling would be expensive, not really needed and has reliability problems, plus no aftermarket shocks for it.... ...the rest of the stuff would be easy, I already have the HD radiator and Mopar Tow Hitch....
 

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The HD fan is a moose of a fan.. 850 watts (60 amps), and a built-in variable speed controller driven by a PWM from the PCM (base fan is a 2-speed relay-controlled fan)
 

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Mongo, I agree that the non-Factory Tow limits is poorly presented and as I also mentioned, it's changed multiple times over the life of the platform.

The Factory Towing option contents vary by model year, trim level and engine choice. There's no one list.
 

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The HD fan is a moose of a fan.. 850 watts (60 amps), and a built-in variable speed controller driven by a PWM from the PCM (base fan is a 2-speed relay-controlled fan)
That is what I was getting at, because it is so different and wired up and controlled different, you just can't buy a HD fan and hook it up to the SD Fan's wiring. One, the connectors are different, Two, they are controlled totally different.... ....you'd need a different wire harness's, splicing, probably electronic modules reconfiguring, perhaps new modules, etc, etc....

The SD fan I've got figured out, its a two stage motor, and the circuit for the low speed has thermister in it on the inside of the shroud. The PCM trips the low relay and powers one of the stages of the electric motor and the thermister varies fan speed from how hot it gets from air coming from the radiator... ...when the PCM decides more cooling fan is needed (probably just water temp hits 222°F) it trips the high relay and powers the other stage of the electric motor and the motor runs at a much higher rpm...

The HD uses PWM on a single circuit, with much heavier wiring for the greater current on a single circuit, somewhere there is a PWM driver for this, and the PCM has to use a different logic for dictating the fan speed through the PWM driver.... ...heck I wouldn't be surprised if the PCM's are different (as in different software, thus have different part numbers)...
Mongo, I agree that the non-Factory Tow limits is poorly presented and as I also mentioned, it's changed multiple times over the life of the platform.

The Factory Towing option contents vary by model year, trim level and engine choice. There's no one list.
And there are hundreds of variables that go into what is needed to properly control a towed load, and you need a safety margin in there too, especially when the OEM's have to build in a huge safety margin, because it always comes back to them no matter how much its the driver's/owner's fault, they are expected to design with the driver/owner being an utter moron in mind.

I used to think the load leveling must be critical to safely handling heavier loads, well simply because it was a suspension change in the TOW package, I know we argued the physics going on behind it, but we agree on the end result, it really is not there to help safely control the tow load, it's just there to level out the vehicle while towing for convenience....

It really appears the rest of the tow package has nothing to do with controlling the tow load better, its too protect the vehicle itself better from the load....
So they may be holding non-tow package limit close to the vest in documentation, either for liability or marketing.... ...they don't want claim something that can be used against them in court nor do they want to make it to look that limited either...

It's also peculiar that the non-tow package limit most often used is the exact same limit that requires a WDH (or am I wrong on the figure for WDH?).... ..almost like they assume someone that TOW's regularly, knows what they are doing, would have a WDH and would make sure to get the vehicle with the TOW Package... ...while someone that got a vehicle without the TOW Package, doesn't tow regularly, doesn't know what they are doing, but needed to tow something as an exception, would probably blow off the WDH, either out of ignorance or simply they can't find one to borrow/rent and are unwilling to purchase one for one time use... ...I can really see a group of people batting about the figure for tow capacity and come to that conclusion, set the limit at where they would need a WDH, cause you know 80% of vehicle owners would try to Tow without a WDH despite stating one is needed for that load.......

And don't get me wrong, I'm not saying I can Tow 7,200lbs with my 2011 Hemi without the TOW Package, like I can get by if I just have to keep a close eye on the engine temp.... ..that is just a recipe for disaster, you will get stuck in a situation you can't pull over right away and you will overheat the engine.....
 

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The WDH requirement starts at 350 lbs of tongue weight (per the manual) although there is certainly a little wiggle room there. I made the mistake of not using one at about 450-475 lbs and it was a very scary ride; thankfully short and local. The front end got really light. And that was with the heavier hemi up front.
 

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The O.M. has a warning that states directly, that loads above 3,500lbs require the use of a WDH.... ....but I see your point, the WDH is for tongue weight..... ....its the same thing with math in between, cause a 3,500 lbs trailer should have at least 350 lbs tongue weight, otherwise it's not loaded correctly.... 10%-15% of forward bias on the trailer, correct?

But a 2,334 lbs trailer could have more than a 350 lb tongue weight.... ....so when talking about if a WDH is needed or not, you talk about tongue weight.... ....total trailer weight is all fine and good, it is related to the tongue weight, and if the tongue weight is off there is something wrong with the trailer and/or how its loaded.... .....its the end result tongue weight that the WDH is for.....
 
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