Transfer Cases on V8

[1998Exp]

Have been hunting for a 2008-2010 with V8 engine with a 4-wheel drive - which seem to be quite rare. I am confused about the transfer case. Was a true 4WD available in that configuration, or all the V8's came with an AWD those years? Thanks!

 

[Dag06XLT]

My 2010 V8 has 4WD (Auto/High/Low)

 

[mgmgmg]

My 2010 V8 Limited has 4WD (Auto/High/Low)

 

[MNgopher]

You'll find they have Auto/4Hi/4Low. No 2 Wheel Drive. In 4Hi or 4Low, it works and feels just like any other part time 4x4 vehicle.

If in doubt, look for the push button switches just above the climate controls.

 

[thebrakeman]

Oh, boy!! Are we getting into the 4x4 vs AWD debate???
-Must have ability to be locked into 2WD
-Must have a low range
-Must be able to lock the center diff
-Must be user-selectable (not fully automated)
-Can't have any automation
-Must have levers (mechanical engagement, no buttons)
-Must have manual-locking hubs (old-school, right?)

But seriously, I hear that some markets (Canada, eh?) and/or certain model years, the 4th gen actually did have some availability with a true 2WD as the default. I've never seen them, but some say they exist.

As far as defining a "true 4WD", 2 definitions of "true 4WD" are almost never the same. So you need to be more specific about what you are looking for.

 

[Butch-Explorer]

Ok from what I read, the 4th Gen (V8 only) will go into a 2wd mode only on the highway after certain speeds and time but drops right back into 4wd or awd hurting after touch the gas pedal too much. Will post the article as soon as I find it again shortly.

 

[Butch-Explorer]

And its not really 2wd when it does it, only limited front 20% 80% rear.

 

[07EddyB]

I have a 2007 V8 4WD. I've read conflicting accounts of how the transfer case works. I will say that when I put my Ex in 4WD it is different from how it drives every day in Auto. When I'm in 4HI (auto) and lose traction it is obvious to me if the transfer case kicks in. Based on my experience, I can't see how the transfer case would be sending power to the front wheels all the time. I understand that there are some AWD vehicles that have the intelligence to vary power front to rear base on wheel slippage but I don't think our Explorers are quite that sophisticated. And, we are talking about true AWD vehicles here - I don't even think the Mounty qualifies as a 'true' AWD vehicle. Will it go into 4WD without input from you? Yes it will - but I would be very surprised if either vehicle was a 'true' AWD beyond marketing speak.

 

[CDW6212R]

AWD means all four wheels are driven all of the time, no kind of AWD or sometimes AWD words abuse. AWD is not the same as an automatic 4WD system, that is A4WD. I don't know later model TC choices, but I doubt that there is a true 4WD transfer case, just the A4WD type which have electronic features, and an internal clutch inside the TC. That system monitors the speed difference of front/rear wheels, and applies the internal TC clutch, whenever it senses a big enough difference.

The 2002+ AWD transfer case was a BW4410, which bolts to any of the same transmissions that came in any 3rd gen. The back trans bell housing is what makes it possible for a TC to attach to it, the V8 and V6 transmission have the same back end bolt pattern. Here's a BW4410, an AWD transfer case, which has one speed and no electronics;

 

[MNgopher]

Since we seem to be muddying the waters some...

Yes, the transfercases in the Explorer are smart enough to vary the power to the front and rear wheels based on wheel slippage. Borg Warner calls this Torque on Demand and its been available on the Explorer going back to 1995. It varies from minimal power to a maximum of a 50:50 split of power when asked.

This is the mode the system operates in under 4x4 auto on almost all 4WD Explorers 2006-10. (Mountaineers are Different in this period - and I'm not going there). The Explorer has a Borg Warner 4412.

Putting it into 4 High commands the system to lock itself at a 50:50 power distribution front and rear. It isn't physically locked like a true part time 4x4 system, but the system commands the power distribution to be 50:50 instead of variable.

Explorers also have the 4 Low option, with the lower gearing. Mountaineer transfer cases do not have this.

Argue whether it is 4WD or AWD. Reality is it can and does operate in both modes in how it performs. Perhaps not physically with the electronically controlled coupling when compared to a true part time 4x4 transfer case, but operationally the same.

Wikipedia (yes, I know) actually has some good descriptions of the system under "ControlTrac".

 

[Explorer_PL]

I thought 4410's were behind 5R55, and 4412 behind 6R transmissions.

 

[CDW6212R]

I thought 4410's were behind 5R55, and 4412 behind 6R transmissions.

The 4410 came out in 2002, for both available transmissions. I learned that about ten years back, planning a project. I don't know when the other TC's came out or how Ford used them.

 

[Explorer_PL]

Up until 2005 Ford was using 5R55 in different versions for both 4.0 and 4.6 - that's where the confusion comes from.
The v6 set up did not change much in 06 but the new 3v v8 started using 6R's transmissions and the rear bolt pattern is different I believe where the TC bolts in.

 

[thebrakeman]

It's been my understand that (at least for the 4th gen), V6 vs V8 center diff units were different type.

V8 trucks had 100% torque to rear wheels until wheel slip. Then an electronic clutch directed torque to the front wheels. I can't remember if it could move more than 50% or not. It could also electronically lock at 50/50. This applied to V8 Explorer and V8 Mountaineer the same (just no low range). And I can confirm that my Mounty operates in this way. So, just because the marketing guys put "AWD" on the hatch, that does not mean it has torque going to all 4 wheels all the time.

V6 trucks had some relatively small amount of torque (10-20%, I forget) going to front wheels all the time, until wheel slip. I think they called the V6 center diff a viscous coupling. Again, V6-Explorer an V6-Mountaineer was the same (just no low range).

Other SUVs operate differently, and will badge them differently. What it's called means very little.

 

[Christobal65]

I have to agree with thebrakeman. The auto 4x4 is anything but seamless and the truck very much acts like it has no power to the front until it detects slip at the rear. At this point it sends power to the front and really seems to jerk the truck forward.

To me it's similar to the how Ford/ZF say they 6R60 is capable of fully locking the torque converter in all 6 gears. However in practice it seems to only lock up 4th, 5th, and 6th. Just because Ford and Borg Warner say the TOD TC in the 4th gen V8 is capable of seamlessly engaging the front driveshaft it doesn't mean that's how it is actually working.

 

[thebrakeman]

Yeah, when I'm in the snow, the front-engagement in Auto mode is anything but seemless. Naturally, it's going to quickly transfer torque until the rear slip is no more, then dial it back, only to have to push it forward again. Lock into 4x4, then it's smooth (slippery or deformable surfaces only, please).

And regarding locking the torque convertor, mine will only seem to do that in 4th or 6th. I have a Scangage on my truck, which I watch while towing our camper. I would love to lock into 5th gear, but as we all know, 4th gen OD button locks out 5th and 6th (grrrrrrr!). But even when I leave OD on, sometimes it will hold 5th gear if I'm holding steady on the throttle. But it's never locked the TC in that condition. Let off the gas a bit, and it may shift to 6th, then may lock TC. Or give it more gas, and it may shift to 4th, then may lock TC. But never 5th with locked TC. Again....grrrrrrr!

 

[Christobal65]

Not to get too far off topic, I use Torque Pro to monitor mine. I have gotten 5th to show as locked, but it is not normal operation. I was towing a mild load, about 2500-3000lbs, I was going up a slight incline at 60-65. I let it hunt between 5th and 6th a couple of times and the TCM learned it needed 5th and locked it up.

 

[GeorgeH]

A sort of off topic question- I've got a 2006 V8 Ltd. If I'm towing a small trailer (about 2,000 lb) and have about 1,500lb on board the explorer would you lock out overdrive? I've heard always to lock out on towing, but it really seems like in my situation the loads not there. Maybe if I get into some hills but other than that it doesn't seem necessary. Anybody have opinions?

 

[michael loibl]

I wish you could just lock out 6th so you could run 5th gear with converter locked on the V8, but being I’m a V6 owner, all I could say is that I would lock out my OD 5th gear, Which would run me in 4th lock up around 2,400 rpm at 60 MPH

 

[CDW6212R]

I wish you could just lock out 6th so you could run 5th gear with converter locked on the V8, but being I’m a V6 owner, all I could say is that I would lock out my OD 5th gear, Which would run me in 4th lock up around 2,400 rpm at 60 MPH

The high loads and high throttle are what kill the OD band or similar trans parts. If you have a load of more than say 2000 or more, that's a good level to begin avoiding OD. The hills and higher throttle is where the OD is very bad to combine, at light throttle ad not severe loads, OD isn't going to be hurt.

That rpm at speed needs to be well over 2000rpm with any decent sized loads. Lower rpm's like in OD puts more stress on the transmission. So try stay in gears that keep the rpm's higher than normal when towing much.