Rear locking differential only on Tremor?

[DieselMonk]

Just for fun I built a new 2025 Expedition in 3 different flavours on the Ford.com website. To my surprise lot of them had the HD tow package standard? However I only see the eLSD on the Tremor as standard, on the Platinum and King Ranch it didn’t come with it and also not available as an option? Weird.
To me the eLSD is one of the best option to get.

 

[LokiWolf]

100 Percent agree. I would not get another Expedition without it.

 

[3rd Expyowner123]

My 2018 has locking e-lsd however I really have not used it. I never drive off road, the few times I have been in Colorado mountains in snow I used 4A, without locking the diff and pulling my boat out of the water I use 4L without locking and have never had an issue.
However, I think my truck has a limited slip diff whether or not it is locked. Perhaps some other members can clarify my statement. It is also noteworthy that my rear differential needed repaired under extended warranty, not exactly sure what work was performed, but suspect issue with the clutch pack.

 

[Calidad]

It does come on other trims in heavy tow pack form. I think the issue is with marketing the Tremor (4x4 people marketing package simply calls it out)

As for its usefulness. Only time I’ve been stuck in all my 4x4 wagons was when they lacked rear locker.

The bigger the wagon the more important that stupid locker gets.

 

[Going_Going_Gone]

My 2018 has locking e-lsd however I really have not used it. I never drive off road, the few times I have been in Colorado mountains in snow I used 4A, without locking the diff and pulling my boat out of the water I use 4L without locking and have never had an issue.
However, I think my truck has a limited slip diff whether or not it is locked. Perhaps some other members can clarify my statement. It is also noteworthy that my rear differential needed repaired under extended warranty, not exactly sure what work was performed, but suspect issue with the clutch pack.

Traction Control in a way serves as a form of limited slip in vehicles w/o a dedicated limited slip differential.

 

[DieselMonk]

My 2018 has locking e-lsd however I really have not used it. I never drive off road, the few times I have been in Colorado mountains in snow I used 4A, without locking the diff and pulling my boat out of the water I use 4L without locking and have never had an issue.
However, I think my truck has a limited slip diff whether or not it is locked. Perhaps some other members can clarify my statement. It is also noteworthy that my rear differential needed repaired under extended warranty, not exactly sure what work was performed, but suspect issue with the clutch pack.

One of its best features is it works awesome. It’s more than a plain locker as it will shift power from one side to another. No intervention necessary, no button nor anything.

 

[Calidad]

The older e-lock with button easily activated by mistake had lots of burnt up clutch packs. Kinda like driving with the ebrake on. Ford moved it and got rid of the accidental activation via stuff being set on it on the center console. All of us with that button have set something on it and triggered it at some point. I bet 90% don’t notice till they get a over heat diff warning on the dash.

 

[DieselMonk]

The older e-lock with button easily activated by mistake had lots of burnt up clutch packs. Kinda like driving with the ebrake on. Ford moved it and got rid of the accidental activation via stuff being set on it on the center console. All of us with that button have set something on it and triggered it at some point. I bet 90% don’t notice till they get an over heat diff warning on the dash.

I never needed to press that button yet, but I surly can feel the power shifting side to side helping me making a tighter turn or push the rear end over a little. Specially in town making 90 degree turns. As for the locking button location, it is right under the gear selector. Not sure why that position is better than any other? Almost any flat mounted button mounted on a center console would ask for trouble.

 

[Calidad]

Limited slip diffs have been around for eons they don’t shift power when turning. They limit outside wheel spin when turning on slick surfaces.

 

[bb37]

The traction control system will apply the brake caliper to the spinning wheel in order to stop the spin and shift the torque to the opposite wheel. That's the power shifting side to side that you feel.

The electronic limited slip differential (eLSD) that Ford uses allows you to engage or disengage the LSD from the drivers seat. When the LSD is engaged and it senses a spinning wheel, it locks up the differential so both wheels spin.

 

[LokiWolf]

Several statements in this Thread that need correction and clarification. This has been discussed and clarified in this Forum SO many times. I really should make a Sticky for this.

Clarify terms and the differences:

ELSD - Electronic Limited Slip Differential. It is Electric Motor based clutches. It never Locks. It has a simulated lock mode that uses the clutches, but can fail under extreme use and default to open. Advantages over a mechanical LSD, is speed, and the ability for the computer to preemptively engage it based on other sensors.

ELD - Electronic Locking Differential. Electronic Pin locked differential. Both sides spin the same speed. Either operates as a solid, or an open differential, and has ZERO function as limited slip. Modern F150's and F250's have this as an option, and not the ELSD. It appears the 2025+ Tremor Expedition might have this instead of the ELSD, because of its advantages off road, and not to have the overheat issues again when off road.

If your Expedition is equipped with the ELSD, it is ALWAYS active, EVEN when TC or AdvanceTrac are off, just like a standard mechanical LSD would be. The button on the console, does not turn ELSD on and off, it turns simulated Lock on and off. It only should be used when you need absolute traction, and should not be used on dry pavement, if you are going to be turning(I used it to get my best 0-60). It will overheat the clutches and can cause issues if used on dry pavement when turning.

The standard LSD in the 15-17 Expedition was flaky, and if not maintained just right could have issues. The ELSD was night and day different in the 4th Gens. It made these big beasts way more sure footed than they should be even in 2WD. I assume the ELSD is going to continue as a option or standard in the 5th gen, but I can't see any stickers to confirm that.

I wish from a daily drive standpoint that my 150 had the ELSD, but when I am Off Road on a back trail climbing a rock ledge, I am glad I have the ELD.

Also, clarity, the ELSD sends torque to where it is needed under normal conditions. It doesn't just "lock" when it senses spin. It will use the clutches to drive the outside wheel faster to help with rotation if Advancetrac senses it is needed. It can apply torque separate to each wheel. It is an LSD, with SO many advantages.

 

[LokiWolf]

Limited slip diffs have been around for eons they don’t shift power when turning. They limit outside wheel spin when turning on slick surfaces.

Edit and to clarify, @Calidad actually said this statement incorrectly above but said it correctly later in another post.

LSD, actually more evenly distribute power across the axle. When coming out of a corner the weight transfers, and typically the inside wheel starts spinning so the outside get less torque and forward progress decreases. Brake based TC, then brakes the inside spinning wheel or pulls torque via engine management, to regain traction. The ELSD prevents this by moving some of that torque to whatever wheel has traction, typically the outside in this case.

 

[Calidad]

The traction control system will apply the brake caliper to the spinning wheel in order to stop the spin and shift the torque to the opposite wheel. That's the power shifting side to side that you feel.

The electronic limited slip differential (eLSD) that Ford uses allows you to engage or disengage the LSD from the drivers seat. When the LSD is engaged and it senses a spinning wheel, it locks up the differential so both wheels spin.

I believe the only rear differential sold in light duty trucks that is a auto locking diff mechanism is GMs g80 rear differential which does not have elocker technology.

Fords elocker diff is a limited slip differential that can be electrically engaged to full locking potential via a switch. When left alone it functions like a normal limited slip differential which restricts inside wheel spin via the same friction clutches thus shifting more drive force to the outside wheel during turns. A good limited slip differential does this in a mild enough way that it doesn’t affect slick surfaces traction yet still limits inside wheel spin.

If your ever in a snowy ski resort parking lot and have a friend with a GMC or chevy truck or Yukon/Suburban
with you. Stand outside by the inside wheel snd have them do a gradual tight turn around you. Every single one of them will break traction on the inside rear tire thus reducing their total traction available to move. Then do the same thing with your Expedition. You will see less to no wheel spin due to the limited slip. Then turn on your Elocker and you will see the same type of inside wheel spin the GM with the G80 had.

Any shift in power distribution you feel in the ford when the elocker is off is traction control braking spinning wheels to reduce the risk of traction loss and loss of vehicle control. Not the e locker locking its self (which would actually be very dangerous in low traction situations where your moving.)

 

[LokiWolf]

I believe the only rear differential sold in light duty trucks that is a auto locking diff mechanism is GMs g80 rear differential which does not have elocker technology.

The G80 is a mechanical locking differential, that locks after a bit of slip, and stays locked until force is released. It is a pain to be smooth with this off road, but it serves a purpose and is strong.

Fords elocker diff is a limited slip differential that can be electrically engaged to full locking potential via a switch. When left alone it functions like a normal limited slip differential which restricts inside wheel spin via the same friction clutches thus shifting more drive force to the outside wheel during turns. A good limited slip differential does this in a mild enough way that it doesn’t affect slick surfaces traction yet still limits inside wheel spin.

STOP using the term elocker. The Expedition(other than it appears the new 25 Tremor) does not have a locker. It has an ELSD(Electronic Limited Slip Differential). It is an LSD with a simulated locker, but is not a locker, like the G80 or Ford's ELD in the 150 and 250's.

Any shift in power distribution you feel in the ford when the elocker is off is traction control braking spinning wheels to reduce the risk of traction loss and loss of vehicle control. Not the e locker locking its self (which would actually be very dangerous in low traction situations where your moving.)

IF the Expedition is equipped with the ELSD it CANNOT be turned off by the driver. You could unplug the control unit or disable it in programming, but otherwise it is always on. The simulated lock can be turned on.

Here is the exact unit used in the Expedition.

Eaton IntelliTrac electronic limited slip differential rear wheel drive features

IntelliTrac™ is Eaton’s new electronically controlled limited slip differential, providing fully variable torque distribution from open to full-lock. Powerfu...

youtu.be

 

[Calidad]

The G80 is a mechanical locking differential, that locks after a bit of slip, and stays locked until force is released. It is a pain to be smooth with this off road, but it serves a purpose and is strong.



STOP using the term elocker. The Expedition(other than it appears the new 25 Tremor) does not have a locker. It has an ELSD(Electronic Limited Slip Differential). It is an LSD with a simulated locker, but is not a locker, like the G80 or Ford's ELD in the 150 and 250's.



IF the Expedition is equipped with the ELSD it CANNOT be turned off by the driver. You could unplug the control unit or disable it in programming, but otherwise it is always on. The simulated lock can be turned on.

Here is the exact unit used in the Expedition.

Eaton IntelliTrac electronic limited slip differential rear wheel drive features

IntelliTrac™ is Eaton’s new electronically controlled limited slip differential, providing fully variable torque distribution from open to full-lock. Powerfu...

youtu.be

I used the term elocker because thats what most people call these when they lack the mechanical understanding that friction plates are not the same as a mechanical locking differential.

The G80 is old as dirt and is proven with its well known advantages and disadvantages. I mentioned it because yes its different from the Expeditions friction based differential setup. Which has its advantages and disadvantages. In a fully independent suspension passenger wagon the advantages are more than the disadvantages. .

However its not a mechanically locked differential nor is the Expedition a solid axled extreme terrain vehicle that both takes full advantage of mechanically locked differential and drives/handles like a solid axle vehicle . My Expedition drives and handles more like an old Crown Vic than it drives and handles like my old Landcruiser.

 

[LokiWolf]

I used the term elocker because thats what most people call these when they lack the mechanical understanding that friction plates are not the same as a mechanical locking differential.

The G80 is old as dirt and is proven with its well known advantages and disadvantages. I mentioned it because yes its different from the Expeditions friction based differential setup. Which has its advantages and disadvantages. In a fully independent suspension passenger wagon the advantages are more than the disadvantages. .

However it’s not a mechanically locked differential nor is the Expedition a solid axled extreme terrain vehicle that both takes full advantage of mechanically locked differential and drives/handles like a solid axle vehicle . My Expedition drives and handles more like an old Crown Vic than it drives and handles like my old Landcruiser.

Crown Vic’s weren’t surefooted, but they were predictable.

You keep saying the right things but insist on using the wrong terms. Don’t propagate the wrong info. We have an E-LSD not an E-Locker(Exception might be the 25 Tremor Expedition based on documentation available). The 150’s and 250’s have an E-Locker.

 

[DieselMonk]

I used the term elocker because thats what most people call these when they lack the mechanical understanding that friction plates are not the same as a mechanical locking differential.

The G80 is old as dirt and is proven with its well known advantages and disadvantages. I mentioned it because yes its different from the Expeditions friction based differential setup. Which has its advantages and disadvantages. In a fully independent suspension passenger wagon the advantages are more than the disadvantages. .

However its not a mechanically locked differential nor is the Expedition a solid axled extreme terrain vehicle that both takes full advantage of mechanically locked differential and drives/handles like a solid axle vehicle . My Expedition drives and handles more like an old Crown Vic than it drives and handles like my old Landcruiser.

I prefer the Detroit truetrac LSD over the G80. I actually broke a G80 about 18 years or so ago. The eLSD is a total different animal than the regular LSD. It can do things that a standard LSD cannot do.
The eLSD is also to find in some high end euro cars / SUV’s. Compare these to the Expy SPP with eLSD equipped, it’s a weapon for cheap $$$ and gives them a very good run for the money! @LokiWolf swears by it, so do I. To me it is right now the BEST option must have feature.
Sure, the euro SUVs may be a bit faster (4sec vs 5sec for the Expy) from 0 to 60, but the Expy is bigger and also can tow more!

If I need to be faster than 5 seconds from 0 to 60, I take my modified GT500 out and blow some doors off other cars.

 

[DieselMonk]

Crown Vic’s weren’t surefooted, but they were predictable.

You keep saying the right things but insist on using the wrong terms. Don’t propagate the wrong info. We have an E-LSD not an E-Locker(Exception might be the 25 Tremor Expedition based on documentation available). The 150’s and 250’s have an E-Locker.

I wonder why the 25 Expy Tremor got Rock mode? Right now there isn’t much of good information to come across that specifies what the 25 Expy Tremor exactly has (eLSD or ELD) in the rear axle. At the time and I still think right now Ford still talks about an electronic rear locking differential and it is only available in the Tremor. I couldn’t choose for example an 25 Active or Platinum, add the HD trailer package and then add the eLSD or anything locking on the rear end. Weird.