rear differential locked

[ralix]

Hello, my 2024 rear diff seems to be locked. When making tight turns the rear end shutters like one would expect when both wheels are locked and turning at the same rate. This happened in all modes, 2wd, 4A & 4H. Is there a way to turn on & off the rear diff? No joke, this started after doing a brake torque burnout in 2-wheel rear drive mode.

Thanks for the help!

 

[Rob6805]

Sounds like the ELSD has failed. The button isn't turned on is it?

 

[LokiWolf]

Lock, Unlock, Back up, go forward, Backup, Lock, Unlock. (Lock/Unlock Refer to the simulated lock button)

Do that on level ground, driving straight. Need to only move about 5 feet forward and back.

When you were doing this, what mode were you in? Did you get a diff temp warning?

This is an Expedition, and I am all about performance, but because of it's weight, I would leave the burnouts to the Mustangs.

 

[ralix]

Thanks for the thoughts, Loki are you serious about the lock, unlock etc? That seems like voodoo magic. What do you mean by simulated lock button? I was in sport mode. I did not get a temp warning.

Also, where is the ELSD bottom?

Thanks so much for the quick responses and help.

 

[TheDoug]

In 2018 it's upper right button of drive mode selection. Not sure if same for 24

 

[LokiWolf]

Thanks for the thoughts, Loki are you serious about the lock, unlock etc? That seems like voodoo magic. What do you mean by simulated lock button? I was in sport mode. I did not get a temp warning.

Also, where is the ELSD bottom?

Thanks so much for the quick responses and help.

The lock button in an Expedition, is NOT the same as the F150/250. The Trucks are Pin locks, the Expedition uses Clutches in the ELSD(Electronic Limited Slip Differential), to simulate a lock, by clamping the clutches.

Again, NOT MEANT FOR BURNOUTS. Now that I have said that again...lets try to get you fixed.

Sport mode engages 4A. After you switched to Sport, did you manually press 2H to get out of 4A?

The voodoo I mentioned above is an old school remedy to get a locker to disengage. We are adding a little new voodoo in with the button presses. All with the hopes the clutches will release. They typically fail to disengaged, not engaged, when they fail, so this is an unusual circumstance.

Good Luck...

 

[ROBERT BONNER]

I agree with trying all of the above things first. Also, put the dash display into offroad mode. It would be interesting to see if it shows the diff "locked" or not. The way I see it, it is either an electrical/logic issue keeping the pressure on the clutches, in which case, I would think it wouldn't take much driving to show some sort (there are many) of overheat/malfunction dash message. Or, your attempt to light up the rear tires on your Expedition might have resulted in major differential mechanical FUBAR condition....

If LokiWolf's suggestions don't work, find out which fuse controls the ELSD and pull it with the truck off. Restart the truck with it out, this will surely generate some unpleasant dash messages, try driving it to see if the rear end has opened or not. If not...you probably experienced a FUBAR situation. If the rear end does open after the fuse removal, reinstall it with the truck off, if the problem returns, there is some sort of electrical/logic issue.

 

[Deadman]

my 2018 did this with 20,000 miles on it. They replaced the entire guts of the rear axle and it went away. Supposedly the locker wasn't releasing and was chattering my rear tires on tight turns. It was kinda embarrassing in parking lots because everyone thought I was in 4x4 lol.

 

[terr5178]

I just read similar issues was fixed by adding fluid to diff some limited slip fluid. Not sure the name but was in a post on this site

 

[JExpedition07]

The issue with the Expedition is that they are really calling an LSD a “locker”. The locker in my F-150 operates off an electromagnetic ball ramp mechanism that pushes several (10) locking pin bars into matching holes on the back of the side gear housing, which locks the axle. Very robust (and good for burnouts!). The Expedition not so much, it’s a clutch based system. F-150s electronic locking axle operation below, as you can see it is a true “locked” condition. No clutch magic, damn marketing department at Ford.