'13 Explorer AWD/4WD

[DASEXPLORER]

I read the descriptions and viewed the videos from the Ford web site as well as postings on this Forum, but I’d still like a little more information on the AWD/4WD system on 2013 Explorer.
Obviously, there’s some kind of transfer case to manage the tough split “front to rear” and maybe some additional torque management in each differential. Are the front and rear differentials “open” or “limited slip” or is torque management handled by applying the brakes?
I’m moving from 2001 Grand Cherokee w/ QuadraDrive to the 2013 Explorer 4WD. With anything Jeep, there a tons of technical information and workings of transfer cases, diffs, etc. But I haven’t found that level of technical information on the Explorer System, yet.
I’d appreciate any details, don’t spare the technicals, I’ll work through it.

 

[peterk9]

I read the descriptions and viewed the videos from the Ford web site as well as postings on this Forum, but I’d still like a little more information on the AWD/4WD system on 2013 Explorer.
Obviously, there’s some kind of transfer case to manage the tough split “front to rear” and maybe some additional torque management in each differential. Are the front and rear differentials “open” or “limited slip” or is torque management handled by applying the brakes?
I’m moving from 2001 Grand Cherokee w/ QuadraDrive to the 2013 Explorer 4WD. With anything Jeep, there a tons of technical information and workings of transfer cases, diffs, etc. But I haven’t found that level of technical information on the Explorer System, yet.
I’d appreciate any details, don’t spare the technicals, I’ll work through it.

Welcome to the Forum :wavey:.
I am not that knowledgeable on the system myself. From what I have been able to gather, there is no transfer case. To quote the Owner's Manual, which can be accessed online, the "vehicle is equipped with an intelligent 4WD system that continously monitors vehicle conditions and automatically adjusts the power distribution between the front and rear wheels. It combines transparent all-surface operation with highly capable four-wheel drive. The system is always active abd requires not driver input........The driver can optimize the 4WD by moving the TMS (Terrain Management System) switch for the correct terrain."
I think the differences in the availablity of the technical specs is likely due to the fact that one is built for extreme off-road driving and the other only for light off-roading.
The manual says that the Limited, with the 20" wheels, is not recommended for off road at all. This I assume is to prevent damage to the low riding rims.
Other members may have more insight into the other technical aspects of the system. Good luck.

Peter

 

[scotted73]

peterk9-
I read through the first and second printing of the owner's manual and found nothing showing that Explorers with the 20" wheels were not recommended for off road use. Could I have missed it or does this only apply to Canadian models?

From Wikipedia:

http://en.wikipedia.org/wiki/Ford_Explorer#Fifth_generation_.282011.E2.80.93.29

Capability
The Explorer is available in either front-wheel-drive or full-time four-wheel-drive. Only one engine was initially available: a standard 3.5L TiVCT twin independent variable camshaft timing V6 (290 hp (216 kW), 255 lb·ft (346 N·m) of torque) mated to a 6-speed 6F automatic with a 6-speed 6F SelectShift automatic as an option.
A second optional engine has less horsepower, but gets better mpg: a 2.0L EcoBoost turbocharged, direct injected I-4 (237 hp (177 kW), 250 lb·ft (340 N·m) of torque) mated to a 6-speed 6F automatic. The I-4 engine will not be available with the optional 6-speed 6F SelectShift automatic and will only be available in front-wheel-drive form.[24][25]
The Explorer is available with automatic Intelligent four-wheel drive featuring an variable center multi-disc differential with computer controlled lock.[26] Conventional front and rear differentials are used with 3.39:1 gearing. The center multi-disc differential controls the front-to-rear torque split, biasing as much as 100 percent of torque to either the front or rear wheels.[27] Depending on the Terrain Management mode selected, the center multi-disc differential's intelligent lock will allow for a 50:50 torque split in off road conditions.[27] The power take off (PTO) unit includes a heavy-duty dedicated cooling system to allow the four-wheel drive system to supply continuous non-stop torque delivery to all four wheels indefinitely, without overheating.[28] "4WD" badging is also included on the rear liftgate.[29][30] Explorer’s overall off road crawl ratio is 15.19:1 with high range gearing only.
Off road electronics include Hill Descent Control (HDC), Hill Ascent Assist (HAA), four-wheel electronic traction control and Terrain Management.
Four-wheel electronic traction control (ABS braking) is employed to simulate differential locks via aggressively "brake locking" the front or rear differentials, transferring up to 100 percent of torque from side-to-side.[26][31][28] In the right conditions, the Explorer can keep moving even if only one wheel has traction, regardless of which wheel it is.
Terrain Management will include four selectable modes. Each mode can be selected via a rotary control dial on the center console, aft of the transmission shifter.



This should give you a start.

 

[Sgt1411]

DasExplorer

I was lucky enough to be involved in the development of the new Police Interceptor program at Ford. Through these interactions with the engineers it was a great opportunity to learn about the AWD drive systems in use on the Interceptors

Having driven the 2011 4WD Explorer at home and then many different police prototypes with different programming it was amazing to see what the engineers can do with software on these new systems.

The Interceptor Utility (Explorer) has the same system we have but let me tell you it drives nothing like a retail Explorer.

The 4WD system in retail is essentially FWD until wheel slip is detected or WOT but the Explorer is truly tuned as an AWD system in the police version

In the retail 2011 I noticed torque steer under WOT, in the 2013 I have now I don't feel it. So I asked and was told they upgraded the Power Transfer Unit hardware and software in 2013 and reprogrammed it with the integrated EPAS.

The police system is power to all 4 wheels pretty much all the time especially in the EcoBoost Interceptor. The transmission is tuned to hold higher revs longer before upshift, kinda like retail Tow/Haul Mode.

Try Tow/Haul mode with TMS set to SAND mode and you will see what I mean.

 

[peterk9]

peterk9-
I read through the first and second printing of the owner's manual and found nothing showing that Explorers with the 20" wheels were not recommended for off road use. Could I have missed it or does this only apply to Canadian models?

From Wikipedia:

http://en.wikipedia.org/wiki/Ford_Explorer#Fifth_generation_.282011.E2.80.93.29

Capability
The Explorer is available in either front-wheel-drive or full-time four-wheel-drive. Only one engine was initially available: a standard 3.5L TiVCT twin independent variable camshaft timing V6 (290 hp (216 kW), 255 lb·ft (346 N·m) of torque) mated to a 6-speed 6F automatic with a 6-speed 6F SelectShift automatic as an option.
A second optional engine has less horsepower, but gets better mpg: a 2.0L EcoBoost turbocharged, direct injected I-4 (237 hp (177 kW), 250 lb·ft (340 N·m) of torque) mated to a 6-speed 6F automatic. The I-4 engine will not be available with the optional 6-speed 6F SelectShift automatic and will only be available in front-wheel-drive form.[24][25]
The Explorer is available with automatic Intelligent four-wheel drive featuring an variable center multi-disc differential with computer controlled lock.[26] Conventional front and rear differentials are used with 3.39:1 gearing. The center multi-disc differential controls the front-to-rear torque split, biasing as much as 100 percent of torque to either the front or rear wheels.[27] Depending on the Terrain Management mode selected, the center multi-disc differential's intelligent lock will allow for a 50:50 torque split in off road conditions.[27] The power take off (PTO) unit includes a heavy-duty dedicated cooling system to allow the four-wheel drive system to supply continuous non-stop torque delivery to all four wheels indefinitely, without overheating.[28] "4WD" badging is also included on the rear liftgate.[29][30] Explorer’s overall off road crawl ratio is 15.19:1 with high range gearing only.
Off road electronics include Hill Descent Control (HDC), Hill Ascent Assist (HAA), four-wheel electronic traction control and Terrain Management.
Four-wheel electronic traction control (ABS braking) is employed to simulate differential locks via aggressively "brake locking" the front or rear differentials, transferring up to 100 percent of torque from side-to-side.[26][31][28] In the right conditions, the Explorer can keep moving even if only one wheel has traction, regardless of which wheel it is.
Terrain Management will include four selectable modes. Each mode can be selected via a rotary control dial on the center console, aft of the transmission shifter.



This should give you a start.

In my Ownre's Guide, it is shown in the Introduction section (pg 7, 2011 Guide 1st print).

"NOTICE TO OWNERS WITH 20 INCH WHEELS AND TIRES

When equipped with 20" wheels and tires the vehicle is designed for on-road use only and not off-road use."

It then goes on further to discuss the possible 'flat spotting' that may be felt after being parked for a period of time.

Since both U.S. and Canadian models use the same wheels and tires, it would apply across the board.

As for the capabilities described by wikipedia in your post, I don't believe that it is possible to lock the vehicle into AWD on a full time basis. Even using the TMS only changes, I believe, the shift points and power distribution as required under the circumstances.

Peter

 

[DASEXPLORER]

Thanks for the information, the best I've read so far. I'm feeling better about the 4WD/AWD system all the time. From the descriptions provide by Forum replies and what I could find early on when considering new vehicles, I feel the Ford Explorer 4WD was by far the best choice and a good value.
The EX should hit the dealership this coming Wednesday and I’ll pick it up on Thursday. Once I’ve had a chance to motor around for a few months, I’ll probably start looking at performance upgrades. Don’t plan to do too much; but will most likely install a K&N Air Intake Kit and maybe a Cat-Back Exhaust system if I can find enough data that shows that to be an improvement.
I read somewhere on a Forum (maybe this one) about Intake Kit install and some Dyno & MPG data to back it up. But that’s for another day.
Thanks again for all the replies.

 

[peterk9]

Thanks for the information, the best I've read so far. I'm feeling better about the 4WD/AWD system all the time. From the descriptions provide by Forum replies and what I could find early on when considering new vehicles, I feel the Ford Explorer 4WD was by far the best choice and a good value.
The EX should hit the dealership this coming Wednesday and I’ll pick it up on Thursday. Once I’ve had a chance to motor around for a few months, I’ll probably start looking at performance upgrades. Don’t plan to do too much; but will most likely install a K&N Air Intake Kit and maybe a Cat-Back Exhaust system if I can find enough data that shows that to be an improvement.
I read somewhere on a Forum (maybe this one) about Intake Kit install and some Dyno & MPG data to back it up. But that’s for another day.
Thanks again for all the replies.

If you watch Motor Week at all, they had a feature on air filters and the statement made was that changing filter types has no effect on fuel mileage in today's modern vehicles. I'm assuming that is because the engine software will compensate for more or less air volume thereby keeping evrything running at peak performance.
Don't forget that the engine is tuned for optimum performance with the OEM parts in place. Changing any of those may require a 'retuning'. Not sure if that may have any warranty implications down the road aside from the replaced parts.

Peter

 

[scotted73]

peterk9,
I checked my hard copy (2nd printing) and the digital copy (2nd printing) and the digital copy (1st printing) and still did not find a reference to the 20" wheels. Regional perhaps?

I don't believe the post suggests actually locking the Explorer into AWD as much as allowing the power to be distributed as needed without overheating the components.

 

[peterk9]

peterk9,
I checked my hard copy (2nd printing) and the digital copy (2nd printing) and the digital copy (1st printing) and still did not find a reference to the 20" wheels. Regional perhaps?

I don't believe the post suggests actually locking the Explorer into AWD as much as allowing the power to be distributed as needed without overheating the components.

Looks like it has been removed. I just checked the online 2011 4th print and it is no longer there. It was between the Special Notices and Data Recording sections.
It would make sense thought to not use it off-road because of the limited clearance between the rim and any rocks etc that you may encounter. I use the 17" steel wheels in Winter and feel much more comfortable around curbs etc because of the higher sidewall. I'm likely one of the few that would have taken OEM 17" wheels if they had been an option on the Limited.

Peter

 

[Sgt1411]

If you watch Motor Week at all, they had a feature on air filters and the statement made was that changing filter types has no effect on fuel mileage in today's modern vehicles. I'm assuming that is because the engine software will compensate for more or less air volume thereby keeping evrything running at peak performance.
Don't forget that the engine is tuned for optimum performance with the OEM parts in place. Changing any of those may require a 'retuning'. Not sure if that may have any warranty implications down the road aside from the replaced parts.

Peter

Thats exactly the feedback that I got from one of the Explorer engineers. He said don't waste your money.

 

[ccarles]

Following these comments I would like to tell you about an experience that I had yesterday coming down a long, paved mountain road. First when I was going up the mountain I used the descent control (I don’t know if I should have), them when I was going down the descent control disengaged I was left with the selectshift in first and the breaks to go down the mountain. I was really sacred that if the breaks fail I will have no control. The information system indicated that the transmission was overheated.
I finally made it down the mountain, but I started to investigate and all my friends told me that they come down with the transfer on low and they don’t need to break. This I new and I thought that the Explorer Descent Control did that but for all I read here it seems to be that this system works mainly using the breaks ABS system.
Can any body through so more light into this. Should I use the descent control going uphill? Or should I wait until I start going downhill so it won’t overheat? Or should I just orget about going to the mountains in the Explorer

 

[peterk9]

Following these comments I would like to tell you about an experience that I had yesterday coming down a long, paved mountain road. First when I was going up the mountain I used the descent control (I don’t know if I should have), them when I was going down the descent control disengaged I was left with the selectshift in first and the breaks to go down the mountain. I was really sacred that if the breaks fail I will have no control. The information system indicated that the transmission was overheated.
I finally made it down the mountain, but I started to investigate and all my friends told me that they come down with the transfer on low and they don’t need to break. This I new and I thought that the Explorer Descent Control did that but for all I read here it seems to be that this system works mainly using the breaks ABS system.
Can any body through so more light into this. Should I use the descent control going uphill? Or should I wait until I start going downhill so it won’t overheat? Or should I just orget about going to the mountains in the Explorer

Welcome to the Forum ccarles. :wavey:
I don't know why you would have engaged Hill Descent Control (HDC) while going UPHILL. HDC will only work when vehicle speed is between 3 and 20 mph (5 - 32 km/h). Above those speeds, HDC will remain 'armed' but descent speed cannot be set or maintained. HDC when used over a long period, will require a cooling down interval and there will be a warning, visual and audible. This all covered in the Owner's Guide. You likely would have been better to gear down using the select shift and use your BRAKES from time to time if needed.

Peter

 

[Jwhcars]

I don't have an answer to the hill descent control on our Explorers. I have owned several Land Rovers and the control knob looks about the same. Ford did own Land Rover for a brief time and may have borrowed a similar system. I took th LR off road in some pretty difficult places and the hill descent worked amazingly. There was one hill that a roll of toilet paper was handed out before you went down. Put the LR in low turn on the
hill descent and hold on - oh yes if you did not make an immediate right turn at the bottom you ended up in a pond.
I will try out the hill descent as soon as possible. I have a feeling it is the same.
I also never used hill descent to go up hill.

 

[Jwhcars]

As posted above the hill descent does not work over 20 mph you have to use brakes !!
Ask me how I know.

 

[LocDoc]

As for the capabilities described by wikipedia in your post, I don't believe that it is possible to lock the vehicle into AWD on a full time basis. Even using the TMS only changes, I believe, the shift points and power distribution as required under the circumstances.

Peter

The four-mode Terrain Management System (TMS) is networked into the vehicle’s engine, transmission, throttle response, anti-lock breaking system (ABS), electronic stability control (ESC), four-wheel electronic traction control, and the variable center multi-disc differential.

The term "differential" in "center multi-disc differential" is relative. Its actually a "center multi-disc clutch", that allows differential action between the front and rear wheels. A differential is any device which can allow for differential action, and may or may not employ gears.

TMS controls every component (listed above) that is related to the four-wheel drive system. TMS is not just "pretty lights on round knob". There are serious changes made when the selector is move out of Normal mode and into one of the off road modes.

Which is why owners are warned not to drive the Explorer on dry pavement with Terrain Management in one of the off road modes, and also why it resets itself back to Normal mode after the engine is shut off and restarted.

One of the serious changes that Terrain Management makes is the multi-disc differential is allowed to lock for a 50:50 torque split during off road conditions.

In Normal mode the multi-disc differential is not allowed to lock. If it did, drivetrain binding and torque windup would occur, the same as driving a part-time four-wheel drive on pavement. Everyone should know that has dire consequences.

 

[peterk9]

The four-mode Terrain Management System (TMS) is networked into the vehicle’s engine, transmission, throttle response, anti-lock breaking system (ABS), electronic stability control (ESC), four-wheel electronic traction control, and the variable center multi-disc differential.

The term "differential" in "center multi-disc differential" is relative. Its actually a "center multi-disc clutch", that allows differential action between the front and rear wheels. A differential is any device which can allow for differential action, and may or may not employ gears.

TMS controls every component (listed above) that is related to the four-wheel drive system. TMS is not just "pretty lights on round knob". There are serious changes made when the selector is move out of Normal mode and into one of the off road modes.

Which is why owners are warned not to drive the Explorer on dry pavement with Terrain Management in one of the off road modes, and also why it resets itself back to Normal mode after the engine is shut off and restarted.

One of the serious changes that Terrain Management makes is the multi-disc differential is allowed to lock for a 50:50 torque split during off road conditions.

In Normal mode the multi-disc differential is not allowed to lock. If it did, drivetrain binding and torque windup would occur, the same as driving a part-time four-wheel drive on pavement. Everyone should know that has dire consequences.

There is no specific warning in my Owner's Guide telling me not to use settings other than Normal mode on dry pavement. There have been posts on this forum where some owners have been using Sand mode on dry pavement to improve 'get up and go'. The book does say that you should switch to Normal when conditions no longer require the use of the other modes.

http://media.ford.com/article_display.cfm?article_id=32417

Peter

 

[13Sport]

There is no specific warning in my Owner's Guide telling me not to use settings other than Normal mode on dry pavement.

Screenie from the manual.. clearly stating that sand and mud/rut modes are off-road only.

 

[peterk9]

Screenie from the manual.. clearly stating that sand and mud/rut modes are off-road only.

13Sport, you are 100% correct. I read that initially but I guess because I was focused on the Normal mode, it didn't register. My bad.

Peter

 

[LocDoc]

One should never follow what others do, they are not always right. Using the off road modes on pavement will hurt the vehicle in the long-run (in some cases it may void the warranty if such action is deemed applicable), and you put your life and the lives of others on the road, at risk.

Sand mode and Mud & Ruts mode modify the electronic stability program, ABS, and turn off other vital safety systems. In addition, they completely remap the throttle response system and the four-wheel electronic traction control. These changes are what make those off road modes dangerous for highway use. Not to mention the four-wheel drive system can lock, causing binding and torque windup.

Land-Rover programmed those Terrain Response System modes for off road used only. Ford’s Terrain Management is nothing but Terrain Response. Their programming and features are virtually identical.

The programs are tweaked to allow for physical or mechanical differences per vehicle. For example the system’s calibration in a Range Rover Evoque, and full-size Range Rover are not the same, as they have different engines, gear ratios, and so forth.

Likewise, the system is specially calibrated for the Explorer. It had to be re-calibrated for the 2013 Explorer Sport, as its 3.5 liter EcoBoost engine outputs more torque. The system has to take that increase in torque into account.

Other than those small tweaks, Terrain Response and Terrain Management perform exactly the same, mode-for-mode. Land-Rover also warns not to use Sand or Mud & Ruts on pavement. Grass/Gravel/Snow mode is also not recommended for use on dry pavement. Snowed-over roads should be fine.

 

[13Sport]

13Sport, you are 100% correct.

Aren't I always? j/k