Expedition Limited vs Platinum

[ExpeditionAndy]

If you get the hd towing pkg, you get the two speed transfer case and lsd as well. If you want the 4l/4h option, you gotta get the tow option or the fx4 option.

That's not quite correct. This was a Limited 4X4 with the HD tow package but it did not have the 4L. It did have the locking rear differential.

Duh - Just saw it (1/23/18). I don't know what the hell I was thinking. Sorry for the confusion.



Here you can see the trailer steering assist on the dashboard.

 

[edizzle]

That's not quite correct. This was a Limited 4X4 with the HD tow package but it did not have the 4L. It did have the locking rear differential.

View attachment 23427

Here you can see the trailer steering assist on the dashboard.

View attachment 23428

Huh? Look closely Andy. It is there!!

 

[bkanic]

Just a note there, i have the Plat with HD tow, you get 2H, 4A, 4L. and the ele lock rear dif. no option for 4H (not that you really need it)

Okay, maybe I messed up the lingo. What I’m after is the rear locking differential option for 100% certanity in the snow. But after reading the owners Manuel above (thank you) it warns not to use 4H on dry surfaces. If I engage the Rear Locking Differential, ion dry surface does the same warning apply or is locking the differential different from 4H and 4L?

 

[bkanic]

That's not quite correct. This was a Limited 4X4 with the HD tow package but it did not have the 4L. It did have the locking rear differential.

View attachment 23427

Here you can see the trailer steering assist on the dashboard.

View attachment 23428

Would you rather use 4A or Locking Diff in the snow? Why?

 

[bkanic]

Would you rather use 4A or Locking Diff in the snow? Why?

And if there is someone here that had a Tahoe with AWD and now has a 4x4 expedition, I would love to hear your experiences in driving each and which system you prefer.

 

[shane_th_ee]

Okay, maybe I messed up the lingo. What I’m after is the rear locking differential option for 100% certanity in the snow. But after reading the owners Manuel above (thank you) it warns not to use 4H on dry surfaces. If I engage the Rear Locking Differential, ion dry surface does the same warning apply or is locking the differential different from 4H and 4L?

There’s *three* differentials on the 4 wheel drive expeditions. A “center” differential which divides the engine power between the front and rear drive axles (via the front and rear drive shafts), the “front” differential which divides power between the two front wheels and the “rear” differential which divides power between the two rear axles. On the truck pictured, the center differential can be manually locked by selecting 4A and the correct terrain setting OR by selecting 4L. The rear differential can be manually locked (in any drive mode) by pressing the little button to the top right of the drive mode selector. I don’t believe the front differential can be locked.

 

[bkanic]

There’s *three* differentials on the 4 wheel drive expeditions. A “center” differential which divides the engine power between the front and rear drive axles (via the front and rear drive shafts), the “front” differential which divides power between the two front wheels and the “rear” differential which divides power between the two rear axles. On the truck pictured, the center differential can be manually locked by selecting 4A and the correct terrain setting OR by selecting 4L. The rear differential can be manually locked (in any drive mode) by pressing the little button to the top right of the drive mode selector. I don’t believe the front differential can be locked.

Thanks, im trying to assess whether or not I need the Locking Differmtil button (for when I buy my truck)

I’m bring this up because my wife’s 2010 Lexus Rx is supposedly AWD. But It has been less then capable at times, There is a locking diff button but it turns off when you hit 26miles/h (40km/h) and you have to keep turning it back on every time you stop at a red light. The snow mode just applies breaks to keep from slipping (this is very danergeous on a left hand turn) so we don’t use it.

I want to make sure that in the snow I can either lock the differtial by button or know that I can rely on 4A (with or without snow mode) on the expedition

 

[shane_th_ee]

Thanks, im trying to assess whether or not I need the Locking Differmtil button (for when I buy my truck)

I’m bring this up because my wife’s 2010 Lexus Rx is supposedly AWD. But It has been less then capable at times, There is a locking diff button but it turns off when you hit 26miles/h (40km/h) and you have to keep turning it back on every time you stop at a red light. The snow mode just applies breaks to keep from slipping (this is very danergeous on a left hand turn) so we don’t use it.

I want to make sure that in the snow I can either lock the differtial by button or know that I can rely on 4A (with or without snow mode) on the expedition

Not to toot my own horn, but you might find this thread helpful:

http://www.expeditionforum.com/threads/all-about-4-wheel-drive-systems-and-modes.34413/

Note that I did not address the *rear* differential. All the binding problems related to the center differential during turns apply to a locked rear differential. Personally, I'd spring for the trailer tow package for snow use simply for the limited slip rear differential*. (The locking bit is nice, but not really required.) Otherwise you have open front and rear differentials. In snow, if you're trying to start and don't have traction on opposite corners, say front right and rear left, open differentials will transfer all the engine power to the two wheels that don't have traction and you'll be stuck! The limited slip rear differential will let the wheel without traction spin up to some speed and then it will start transferring power to the wheel with traction. Ok, for the 4x4 sans-locking-center-and-rear-differential trucks, the software guys have supposedly gotten smart and are now using the wheel speed sensors to detect a traction loss and will compensate by applying the brake to the spinning wheel which will force power back to the non-spinning wheel. But I'm more of a hardware guy and don't always trust those software guys and gals...

Note that if you just put the thing in "snow" mode, the truck will simply figure out when to lock and unlock the center and rear differentials. Note further, that just putting the thing in "snow" mode will not use the super-nifty 4L mode for slowly descending steep and slippery hills without having to use the brakes.

*Ok, personally, I'd get the trailer tow package because I keep my vehicles for a long time and would want the upgraded radiator for the extra durability. And, really personally, I'm buying mine because we just bought a travel trailer and need a tow vehicle, so I'd spring for the max trailer tow package just for the added towing capacity and the integrated trailer brake controller. Ok, ok, if we're going to get really personal, I ordered the FX4 package for the skid plates and all the goodies listed above. And then I also checked the max trailer tow package which, after checking the FX4 box, only gets you the integrated trailer brake controller and the pro trailer backup assist. I went for it because the integrated trailer brake controller is nicer than having an extra box screwed into some inconvenient location and because I plant to eventually teach 5 other drivers how to tow...

 

[jgudnason]

Would you rather use 4A or Locking Diff in the snow? Why?

I have used 4A in the snow, and it's great.

one comment above i just wanted to clarify after doing much research myself, and differences between AWD and 4A. The truck doesnt have a center diff, it has a variable transfer case. in the case of a diff, 100% of torque can be directed in either direction. with the transfer case, as the drive shaft goes through the transfer case to the rear axle, you can never disengage the rear, and can only really go up to 50/50. But it's a electronically controlled wet clutch which can transfer 0-50 to the front, and basically lock up the clutch to get a 'locked' status.

So the problem with AWD vehicles and snow, (depending on tech, and vehicle computer applying brakes to various wheels), in a purely mechanical sense, you can have one wheel of the four without traction, and all torque applied to that wheel. This problem is compensated for by the computer applying brakes to slipping wheels.

back to the truck. so because it's a transfer case, rear is always getting torque. in 4A, the computer will decide if front wheels also get torque. but unless locked up, the transfer case allows slippage, so you dont get binding in corners.
The limited slip rear diff will intelligently only allow one wheel to slip before transferring torque to the other. (and can be locked up all together with the button)
The front diff doesn't have the locking option, but traction control will do what ADW vehicles do, and apply brakes to wheels which are loosing traction, transferring torque to the other side.
All together, the 4A mode by itself will do a very good job in snow.

if you are stuck, sure, you can lock the rear, which will help, but shouldn't be used on dry pavement due to binding.
Shane_th_ee also correctly mentioned the drive modes. when you put it in snow mode, i believe that basically puts it in 4H (locked transfer case), but again cautions on using this on dry pavement.

99.9% of the time, 4A, and proper snow tiers.

 

[deweysmith]

I high-centered recently on a big pile of snow (I walked right up it trying to get into a slightly too small parallel parking space) and 4A was more helpful than 4H. 4L and some traction aids (kinda like snowshoes) was what really got me out though.

I don’t even have limited-slip. AdvanceTrac made my brakes pretty warm but it did its job well.