[FirstOnRaceDay]

Hi all
My escape has the automatic 4x4. i was just wondering how much it takes for it to actually kick in. i have slide around a couple corners in the recent snow storm and it didnt kick in. when i bought the car the ptu unit went and they had to replace it.

 

[sleeve]

Your 4WD system will engage while you are accelerating or when the computer senses wheel spin at the front wheels when the gas pedal is depressed and you are trying to move the vehicle in a forward direction. Sliding around a corner is a result of too much momentum and this style 4WD can not be used to help steer you back on course. A stability program that activates the brakes to help course correct is probably more likely.

To verify your 4wd system is functioning - just find a empty dirt road. Stop and then hammer the throttle. If the truck takes off without too much fuss from the traction control, than the system is working. If you get a large amount of traction control activation [trying to cut power to the front wheels] than the system might not be working as intended.

So - on snow covered roads a 4WD will accelarate better than a 2WD vehicle. But it's still got to stop and turn so please remeber to drive in a mannor appropriate for the conditions.

 

[wptski]

Ford's "Unintelligent 4WD" engages everytime you leave from a dead stop driving straight or making a turn. Rear wheel torque is supposed to increase if wheel slippage is detected.

 

[escape05xls]

I just try flooring it on snow/ice, mine seems to work. Also up snow covered hills...all the fwd cars were barely going and I just trounced right up.

 

[sleeve]

Right, the operation of the 4x4 system is activated via wheel slip in the front tires. However, for the Escapes system to truly correct your course in a slide, the differentials would need to use Torque vectoring. This would be where all driven power is sent to the wheel that is at the outter most side of the curve you are creating with your vehicle. This would induce an over steer condition and help correct the skid.

But on snow covered roads, the first thing we do in a skid is slam on the brakes. So in this situation it is the traction control and electronic stability control systems [if the Escape has one] that provides the course correction by pulsing the brakes at individual wheels.

Personally, slowing down for corners on snowy roads can prevent any slide and ultimately keeps the blood pressure down for you and the drivers of any other cars on the roads.

 

[wptski]

Right, the operation of the 4x4 system is activated via wheel slip in the front tires. However, for the Escapes system to truly correct your course in a slide, the differentials would need to use Torque vectoring. This would be where all driven power is sent to the wheel that is at the outter most side of the curve you are creating with your vehicle. This would induce an over steer condition and help correct the skid.

But on snow covered roads, the first thing we do in a skid is slam on the brakes. So in this situation it is the traction control and electronic stability control systems [if the Escape has one] that provides the course correction by pulsing the brakes at individual wheels.

Personally, slowing down for corners on snowy roads can prevent any slide and ultimately keeps the blood pressure down for you and the drivers of any other cars on the roads.

That's not correct! Front wheel spin only cause rear wheel torque to increase. Under normal driving conditions "most" torque is sent to the front wheels. The key word is "most" but not all of it. Don't let the sales brochure fool you like it did me! The truth is in the Ford Workshop Manuals and a few articles on-line if you read closely.

You have rear wheel torque every time you leave a dead stop till you reach a steady speed. That why the 4WD's EPA MPG is 3-4MPG lower than a FWD.

 

[skibender]

So that's why I have heard it called an "unintelligent" 4x4. I wonder why slight torque would be applied to the rear wheels on all take offs but the truck is intelligent enough to transfer torque to the rear wheels if the front wheels start to lose traction. This sounds similiar to the system that I had on my 98 Explorer. As you said, the mpg could be improved if FWD was used from stops.

 

[CrashNburn]

ive had my 04 up on the hoist at work, and unless i flip the swtich or give the throttle a quick shot the rear tires dont spin. when i originally looked at buying an escape, i looked for an 04 because it has the user controlled 4x4, i almost bought an 05 until i realized they took the switch out of them. dont forget to keep an eye on the banjo fitting on your transfer case as they are prone to leaking, and the synthetic fliud it takes is 22 bucks for a liter!

ive owned lots of different vehicles, and was a bit learing about the front wheel drive suv thing, but after my first winter with the escape, and then a summer of towing a boat out of a sandy beach. im impressed. my only complaint is the drivers seat, and im a but too tall for the thing.

back on topic.... keep your vehicle serviced properly and you shouldnt have too many problems with the 4x4 system.

 

[wptski]

So that's why I have heard it called an "unintelligent" 4x4. I wonder why slight torque would be applied to the rear wheels on all take offs but the truck is intelligent enough to transfer torque to the rear wheels if the front wheels start to lose traction. This sounds similiar to the system that I had on my 98 Explorer. As you said, the mpg could be improved if FWD was used from stops.

I've used that term in other forums also, so that's probably where you've seen it.

It's not really slight either, easily over 25%. On a full throttle from a dead stop, the highest I've seen is about 30%. I had my 4WD module reflashed because of a TSB about the "hooting" noise on take off which didn't fix the problem and is "now" said to be caused by the transaxle drive chain. Anyway, I noticed 38% on a heavy but not full throttle take off now.

 

[Squishy]

It's similar to Honda's system, and an earlier version didn't even transfer torque on slipping - the engineers determined that slip was impossible if torque was split 50/50 on take-off and then slowly distributed to 100% FWD. I think the new SH-AWD does transfer torque.

 

[sleeve]

You have rear wheel torque every time you leave a dead stop till you reach a steady speed. That why the 4WD's EPA MPG is 3-4MPG lower than a FWD.

I understand that the system moves power to the rear end from a dead stop and that power is moved around when there is wheel spin but I am slightly confused. Are you saying that when you are sliding off the road, torque is applied to the exact wheel that needs it the most or that it's simply sent to the rear end?

 

[Squishy]

"Intelligent 4WD" will just send more power to the rear open differential, but traction control may be able to somewhat direct that torque to the wheel that can use it.

 

[wptski]

You have rear wheel torque every time you leave a dead stop till you reach a steady speed. That why the 4WD's EPA MPG is 3-4MPG lower than a FWD.

I understand that the system moves power to the rear end from a dead stop and that power is moved around when there is wheel spin but I am slightly confused. Are you saying that when you are sliding off the road, torque is applied to the exact wheel that needs it the most or that it's simply sent to the rear end?

If you have AdvanceTrac, wheel spin, and under 62MPH, it's supposed to pulse the brakes of the wheel(s) with poor traction using the ABS. This has nothing to do with 4WD.

4WD: The manual states under normal driving conditions most of the torque is sent to the front wheels but if front wheel spin is detected, rear wheel torque is increased. Under certain driving conditions control of the 4WD is turned over to the ABS module. Manual states lots of facts but doesn't really explain them much!

 

[sleeve]

If you have AdvanceTrac, wheel spin, and under 62MPH, it's supposed to pulse the brakes of the wheel(s) with poor traction using the ABS. This has nothing to do with 4WD.

That's was I was saying originally and then you said it was incorrect.

 

[wptski]

If you have AdvanceTrac, wheel spin, and under 62MPH, it's supposed to pulse the brakes of the wheel(s) with poor traction using the ABS. This has nothing to do with 4WD.

That's was I was saying originally and then you said it was incorrect.

Nope!

You wrote: Right, the operation of the 4x4 system is activated via wheel slip in the front tires and that's not correct. That only increases the rear wheel torque which is sent regardless of front wheel spin. No matter how easily you take off, your going to get 25% rear wheel torque.

A pinpoint test from the workshop manual states to monitor the 4WD PID and make tight turns at <5MPH. If you see at 20% rear wheel torque, return the vehicle to the customer.

Another pinpoint test states to command 100% rear wheel torque as they can do that with their IDS. The vehicle should resist turning.

 

[C17chief]

Been meaning to pick up an interface cable for the laptop for awhile....mainly just to have for general use since everything is all computerized and sensorized these days and I do all my own work (except free warranty work of course). Been meaning to see if I can aquire one of the better full software suites from the usual download sources as well. If I ever put that together, I certainly would hook it up and see exactly what is going on with all that in various situations. Kinda interests me as to what exactly is going on when with it since it is the first "4x4" that isnt really a 4x4. I'm used to things either being 2hi, 4hi, or 4lo, no gray area, no in between, etc. :lol:

 

[wptski]

Been meaning to pick up an interface cable for the laptop for awhile....mainly just to have for general use since everything is all computerized and sensorized these days and I do all my own work (except free warranty work of course). Been meaning to see if I can aquire one of the better full software suites from the usual download sources as well. If I ever put that together, I certainly would hook it up and see exactly what is going on with all that in various situations. Kinda interests me as to what exactly is going on when with it since it is the first "4x4" that isnt really a 4x4. I'm used to things either being 2hi, 4hi, or 4lo, no gray area, no in between, etc. :lol:

I'd be surprised if you find anything consumer grade in software that will show you what you want to see.

I first used a scope to monitor rear wheel torque but now use a Scanguage-II and info from a expert in the area of programming/understanding that unit. The 4WD PID was somehow hacked by using two SG-IIs connected back to back and Ford dealer system. Ford published PID memory locations in their PC/ED manuals up to '06 and stopped there. Many published PIDs fail to work the farther you get away from '06. There was a PCM change made for '09 also probably because of the new 6F35 transmission but that just a guess on my part.

 

[Squishy]

I have an OBD-serial cable that works with some monitoring software that can show me all the standard OBDII parameters, but I'm not sure if that includes rear wheel torque.

 

[wptski]

I have an OBD-serial cable that works with some monitoring software that can show me all the standard OBDII parameters, but I'm not sure if that includes rear wheel torque.

Nope, it won't as the 4WD PID isn't standard/generic OBD-II.