wptski

Leaving from a dead stop on snow is where one needs rear wheel torque and that's when Ford's AWD/4WD system delivers it but on dry hard pavement is where you don't need but still do anyway. How intelligent is their so-called "Intelligent 4WD"?

I've never seen a similiar test on a Ford product. I find the results amazing! You'd think that all of them would at least send rear wheel torque to pass the first part of the test but they don't. Here, somebody gets stuck in snow/ice and thinks it's just so bad that they can't move but it's really the vehicles 4WD/AWD system that doesn't work as you think it would.

MPG is of little concern to me. I was actually looking for another Ranger but at that time there wasn't any '09 on lots yet.

The PTU rotates the driveshaft all the time. BTW, the '11 Explorer has a water cooled PTU. Back when I believed the Ford hype and chased the Hybrid owner to a forum, I went through this same basic conversation. Somewhere along the line I suggested pulling the fuse to increase MPG. I got a big Thank You form one guy posted that he tried and gained 1-2MPG on a common trip that he makes all the time to a cottage. I don't drive that much so 1-2MPG means nothing to me but those Hybrid people talk about 0.3MPG changes! I have never tried it but on my Ranger in 4x4 there was a marked decrease in MPG, no doubt about that. Some other guys with 4x4's claim that thyey could see the gas guage move!! Your theory sounds good but in real life it doesn't seem to pan out.

Another SuperCab 4x4 Ranger.

Not my opinion just the words from Ashok Rodrigues, 4WD technical specialist. It should work as described in the interview which is the way I understood it would before my purchase. If I had known it worked this way, I might be driving something else.

You'd really need that while driving straight away from a stop light! It's so intelligent that it can't detect the lack of need.

Your tag says AWD and mine is 4WD yet it's the same exactly system. Don't be fooled by the name game. Ford does have a system that send torque all the time, I believe I listed one above, a split system. A perfectly true AWD would have a clutch at every wheel which hasn't happened yet. The Fusion/Escape either drives the front or the front and back together. You want to called that AWD?? The best way to describe the system under "normal" driving conditions is that any time your pressing on the accelerator you have rear wheel torque and nothing at a constant speed.

On Demand should mean "only" when needed. You bet, if there's one for the TC, why not the 4WD/AWD.

I'm not upset, I just don't see any reason for the torque. I'd love to hear their reasoning behind it. I've tried to contact Ford asking these quetions but they refer me to my dealer that can't them either. I found a patent with Ashok Rodrigues, 4WD technical specialist's name on it, got his phone number and was tempted to call him but since it was his home phone, I didn't. If you don't have a problem about the way it works, you might be a Ford engineer/employee or just gullible.

It just goes to show one how much BS is out there concerning these 4WD/AWD systems on how/if they really work during bad road conditions.

Yeah, it's supposed to know before a wheel spins to prevent it. I guess it thinks that it's going to spin a wheel on dry hard pavement, another not too intelligent of a system. These forums aren't just for the good statements only but bad also.

The Fusion is a asymmetrical FWD, meaning that it has a short and long half-shafts, so it can suffer from torque steer. Not saying that it does but likely that it can. Once you reach a constant, there is no rear wheel torque. Traction control that uses the ABS doesn'r work above 62MPH but I'm unsure if the 4WD/AWD does or doesn't. BTW: Here's a interesting video about 4WD/AWD comparison testing and torque steer but no Ford products.

It's advertised on a On Demand system and it isn't, so I'm unsure why you say it does. Why is there a dash icon to show you when the traction control activates but not the 4WD/AWD? Yes, I know that indicator is used to turn it OFF and anti-trailer sway mode but why the activation indicator?

You mean that you don't care if something you purchased doesn't work as advertised? If not, your way too easy. Would you like a 1-2MPG increase? You'd get that if it worked as advertised. Find the fuse marked "4WD/AWD" only. Pull it and you gain that 1-2MPG but the dash wrench icon will light up. If you replace the fuse the light will go out. For somebody that does lots of city driving that could add up quickly.

Should a Ford dealer know how it works? They didn't say that we know but can't tell. I asked them how much torque I'd expect to get driving straight as the manual llisted a test and value for a hard turn at <5MPH. Even their Tech Support couldn't supply a answer. If you read the link above of the conversation with the Ford Driveline Specialist outlining the different systems, one is called On Demand which is what the Fusion, Edge, Escape, etc. has. Does it work as described in that interview? Nope! Since that's the case, why should I believe their other claims? After being a machine repairman for Ford for +35 years, I've seen lots of stuff that didn't work as claimed. You many want to take things for granted and the believe their claims, I for one don't! It would have been nice if Ford would have used the 4WD dash icon. Yes, there is one. If you look closely with a flashlight, you'll see it in the upper left-hand corner. Well, at least on a Escape anyway. The manual also states the the rearend unit can overheat and go into a lock-up mode. Your supposed to wait 20 minutes for it to cool down. Just how the driver is supposed to know of the condition isn't mentioned at all.

Zero means just that, no rear wheel torque. When I had a DMM and a scope on the 4WD/AWD module PWM output, zero torque showed zero output. The 35% was full throttle from a dead stop. The guy who worked with Linear Logic on the SG-II and provided the coding in their PDFs, CarlD(DesertDog) orginally based his coding on a 100% being the max but after my scope showed twice what the SG-II showed changed his thinking and changed the MTH value. It's all about taking the raw data and doing the math on it, sometimes guessing. That's why the max rear wheel torque would be 50%. All my values are driving straight from a dead stop. Aside from the 10-20% on light acceleration, your values are the same as mine. I'll have to try to see if I can get less than 20%. Mine had a issue which felt like accelerator play which caused it to lurch on take off. The 10B15 recall(PCM reflash) of the vehicles using the 6F35 transaxle(including the '10 Fusion) cured that, so "maybe" I can apply the accelerator more smoothly now. I retired from Ford and if I was still working, I might have been able to get intouch with somebody cross town to get some answers as I'm in Michigan.

Yes, that is the correct coding after the mistake(50%/100%) was fixed. Values barely visable for me. Mind interpeting? What's the value do you see leaving from a dead stop under light, medium and heavy acceleration or any other time you've noticed a value or lack of?

Well, I don't know what Waldo does for a living. Maybe Waldo should say what that is to qualify them to say that it's different and exactly what that is. How much torque and when is what the whole system is about. The sales hype leads one to believe that it's a On Demand system which it's not. The manual states that under normal driving conditions "most" of the torque is sent to the front which means some goes to the rear, when and how much? Is that too much to ask?? The interview with that Ford Driveline Specialist says that increased throttle is supposed to generate increased rear wheel torque. A large increase just doesn't happen. Just way too many unanswered questions and false claims.

In the Ford WorkShop Manual for the Escape and Fusion the theory of opertion for the 4WD/AWD is exactly the same word for word. How can you say the programming isn't the same? Even "if" there is a small difference in the percentages, nobody knows as it not in the manual. Like my dealer's service shop foreman said, "If it aint in the books then Ford doesn't want us to k know". Now a days, anything complex, Ford tell the dealers what to do step by step. Other than oil seals on the rearend, it's replaced as a unit. Same goes for the EPS(electric power steering), anything with the motor or module and the whole steering colume is replaced. I don't know what you mean that the Ford system doesn't require mechanical slippage to engage the rear. It supposed to send rear wheel torque if it detects front wheel spin. Isn't that mechanical slippage?

The new '11 Explorer is just that all new, all different. Why should that be obvious? It isn't even available yet! What do you call small amounts? No matter how easily you try to press the accelerator, you'll get over 20%. A normal press and you get 25-30%. All the way to the floor and you get 34-35%. I expect to see the max of 50% when mashed to the floor but it don't. The only time I've seen a few percent was coasting down a gradual incline. My main point has been and always will be the fact that it's not a On-Demand System that it's advertised to be.

Explorer? Nope! The '10 Explorer has three different possible systems. The following is a principle of operation of each from the manual. Which one sounds like a Fusion??? Not sure about the SHO but Flex/Tarus appear to have the same system.. Four Wheel Drive (4WD) Systems — All Wheel Drive (AWD) Principles of Operation The automatic, All-Wheel Drive (AWD) transfer case has no external controls. A 2-piece aluminum case houses the assembly. The unit is chain-driven. A differential provides torque to the front and rear transfer case outputs. The differential transmits torque at the ratio of 40% to the front output and 60% to the rear output. Torque flows through the input shaft to the front planetary gear assembly and then outward to the ring gear and upper output shaft. Torque also flows through the front planetary gear assembly to the overdrive sun gear outward to the upper drive sprocket. The torque flow continues from the upper drive sprocket through the drive chain to the lower drive sprocket and then to the front output shaft. The differential provides the connection between the ring gear and the overdrive sun gear. Principles of Operation The 1-speed torque-on-demand transfer case modes are controlled through the 4X4 control module. The modes are: • All-Wheel Drive (AWD) AUTO — torque is supplied to the front and rear driveshafts as needed to maintain traction. AWD AUTO mode can be changed to AWD LOCKED mode by pressing the message center SETUP button; the message AUTO will be selected, press RESET within 4 seconds, then the message LOCKED will be selected and the 4X4 indicator will be illuminated. • AWD LOCKED — torque is supplied to the front and rear driveshafts constantly and the 4X4 indicator will stay illuminated in the Instrument Cluster (IC). This mode is not recommended for use on dry pavement or hard surfaces. AWD LOCKED mode can be changed to AWD AUTO mode by pressing the message center SETUP button; the message LOCKED will be selected, press RESET within 4 seconds, the message AUTO will be selected and the 4X4 indicator will turn off. Four Wheel Drive (4WD) Systems — 2-Speed Torque-On-Demand Principles of Operation The vehicle is equipped with an automatic electronic-shift system that allows the operator to choose between 3 different Four-Wheel Drive (4WD) modes. The operator can switch between 4X4 AUTO and 4X4 HIGH at any speed. To engage or disengage 4X4 LOW modes, the vehicle speed must be less than 3 km/h (2 mph) and the transmission must be in NEUTRAL. Wheel slip is sensed by monitoring the average front and rear wheel speeds. Based on steering wheel angle, Accelerator Pedal Position (APP) and wheel slip, a Pulse-Width Modulation (PWM) signal is transmitted to the transfer case as torque is required. The 4X4 control module will provide the ABS with current clutch duty cycle and whether or not ABS may command the clutch duty cycle. '10 Flex/Taurus Principles of Operation The vehicle is equipped with an All-Wheel Drive (AWD) system, also referred to as Active Torque Coupling (ATC), that is always active and requires no driver input. The system has no Mode Select Switch (MSS). The system continuously monitors vehicle conditions and automatically adjusts the torque distribution between the front and rear wheels. During normal operation, most of the torque is sent to the front wheels. If wheel slip between the front and rear wheels is detected or if the vehicle is under heavy acceleration (high throttle position), the AWD system increases torque to the rear wheels to prevent or control wheel slip. If the spare tire is installed, the AWD system may disable automatically and enter Front Wheel Drive (FWD) only mode to protect driveline components. This condition may be indicated by an AWD OFF message in the message center. If there is an AWD OFF message in the message center from using the spare tire, this indicator should turn off after reinstalling the repaired or replaced normal road tire and driving a short distance. It is recommended to reinstall the repaired or replaced road tire as soon as possible. If the sizes of the tires used on the front and rear axles differ greatly enough, the AWD system may stop functioning and default to FWD or damage to the AWD system could occur. AWD faults may be indicated by the powertrain malfunction (wrench) message center warning indicator in the Instrument Cluster (IC) as well as the Check AWD message center warning indicator in the message center. The system consists of a Power Transfer Unit (PTU), 4X4 control module, rear axle and a solenoid-actuated ATC device. Based on the amount of current sent to the clutch, the module varies the torque sent to the rear wheels by sending a duty cycle to the ATC device, located inside the rear axle. For concerns with the PTU, refer to Section 308-07B. The 4X4 control module also provides the brake system with its current clutch duty cycle and determines whether or not the brake system may take command of the clutch duty cycle.

Nope, here's the paragraph with what I said in bold for you to reread. On-Demand All-Wheel Drive The third type is the on-demand system. An on-demand system is always driving one axle and then drives the other axle as conditions demand. In the case of the Ford Fusion or Ford Edge, the front axle is the primary drive axle. For the Ford Explorer and Mercury Mountaineer, the rear axle is the primary drive axle. Simple mechanical systems use a clutch to send torque to the secondary drive axle when the primary axle starts to slip. Today’s electronic systems — like those found on all Ford Motor Company cars as well as Ford Explorer and Expedition, the Lincoln Navigator and the V-8 Mercury Mountaineer — use a computer controller that monitors such things as steering angle, accelerator pedal position and engine speed to provide the precise amount of torque, front to rear, as needed. “What’s really impressive about these systems is that they don’t just react to slip,” says Rodrigues. “They usually prevent that slip from occurring in the first place. By predicting slip and preventing it, the driver doesn’t feel the vehicle slipping and responding. The operation is seamless.” He says on-demand systems create a smooth, confident driving feel in all weather conditions with much better traction. The systems also help balance and improve driving dynamics by sending torque to the secondary axle when it’s most appropriate for handling. “On a normal front-drive vehicle, the front wheels have a limited amount of traction available to them,” says Rodrigues. “That traction has to be used for moving the car forward and for steering. If you use all of the torque to drive forward, you don’t have anything left to steer with, and vise versa. An AWD system off-loads some of that drive torque to the rear wheels. The harder you accelerate, the more of that torque that’s going to be redirected to the rear wheels, restoring the ability of the front wheels to steer the vehicle while providing an even higher level of acceleration.” But he cautions that while these sophisticated AWD systems do help with acceleration, they won’t make the car stop any faster. “Your traction is much better and your handling is much better,” says Rodrigues, “but AWD does not give you more braking power.”

Agreed, it's always ON but if you read the description of the so-called On-Demand System outlined by Ford's Ashok Rodrigues, he states that it's FWD vehicle till front wheel slippage is detected then it sends rear wheel torque. That's incorrect as even the Ford Workshop Manual states in a vague way by wording it that "most" of the torque is directed to the front under normal driving conditions. This would mean that "some" torque is sent to the rear wheels under normal driving conditions.

Back up a minute. With all this monitoring of throttle, steering angle, wheel speed, etc., why does it send rear wheel torque on dry hard pavement? The sales hype leads one to think that it doesn't like a on-demand 4WD system or only when needed. Where's the need on light throttle while driving straight on dry pavement?