"Electronic Limited Slip Differential Reduced Torque" - Warning message. Used my Spare, msg now comes on periodically after replacing rear tires.

[Bo Simmons]

I could use some help understanding this and ways to get the proper service done before we drive 30 hours to Colorado to use this 4X4.

We have a 2020 Expy with F4 (4x4 options). has 23,488 miles, driven in used in 2H mode 99.9% of the time and driven in Georgia on mild city and highway roads, zero off-roading to date.

We had a nail in the sidewall on a rear tire. The tires had plenty of treads left but I decided to buy 2 matching new rear tires at 23K miles so they were better matched. The tires took 1 day to arrive so they put on my Spare which was a full-sized matching Michelin tire. That night driving home in a light drizzle, the warning 1st came on. Said ""Electronic Limited Slip Differential Reduced Torque" and had a place to click Ok. I clicked ok and message went away till I drove it again then it ceased coming on for a few short drives. I got the 2 new Michelin Defender LTX M/s put on the next day and later that evening, the warning message came on again. It now comes on occasionally (50% of the time) at low speeds, often under 45mph, and even on dry pavement. The dealer here in Savannah is a nightmare - 2 weeks to get a diagnostic appointment and 2-5 days there in the shop to diagnose the issue ( total joke for service but my only warranty choice) - but they are sending a mobile service to try and pull codes to see if it is a wheel speed sensor going/ gone bad.

So, to recap this started when using the spare and continued when we replaced both rear tires with similar Michilen 275-65-18 Defender LTX M/s tires which I've heard shouldn't matter. The original tires were. Michelin Primacy XC and there are still 2 matched on the front.

I could use help or advice as I've see dealers having trouble with ELSD messages. I've reviewed other posts and read deep into this one https://www.expeditionforum.com/threads/2022-check-elsd-service-vehicle-soon.52620/ which contained this info below.

Electronic Limited Slip Differential Reduced Torque
Displays if the electronically limited-slip differential has limited functionality. This could be due to an undersized spare tire or caused by the system overheating. If you have an undersized spare tire installed, replace the spare tire with a full-sized tire as soon as possible. If you do not have an undersized spare tire installed, the vehicle has reduced functionality. Have your vehicle checked as soon as possible.

 

[LokiWolf]

Most likely something related to the Wheel speed sensors. Most likely something got damaged, disconnected, or loose when swapping the wheels around. Got any codes? Have a scanner? Got an Advance nearby that can use more than the 19.95 basic scanner and pull OEM specific codes?

 

[TheDoug]

I agree something else had to have happened during the wheel swap.

I had flat on 3 hour trip to Houston and put the full size spare on rear, drove remaining 2 hours and never got that message. And continued to drive around town on it for 2 days.

 

[GlennSullivan]

The front Primacy and the rear Defenders in the stated 275-65-18 size both show as 32.1 OD and 648 revs per mile so the difference in model should not trigger a rotational speed error.

I would agree with above comments that something happened to either one of the wheel speed sensors, or the cable leading to same. Possibly a loose connector, causing the intermittent error.

 

[duneslider]

One more for something else is wrong. I have used the spare tire WAY more than most and that includes towing for several hours (hundreds of miles) with the spare on the rear in bad weather (mountain snow). I have also used the spare offroad, in 4x4, etc.

Honestly, that seems somewhat cool they will send someone out to check codes and do a little onsite diagnostics.

 

[Bo Simmons]

Hi All - thanks for the great feedback. They came Wed before Thanksgiving and the guy couldn't log in to Ford's servers so he said. He's coming back Tuesday morning. All he does is a mobile service from the Dealer to plug in and pull a code. Hopefully, the speed sensor for the wheel that got pulled 1st (and got the spare), is just unhappy and needs a replacement, but it sounds like it will be a service visit either way.

I'll close out this post when I get it resolved or give some updates. Fingers crossed!

 

[Bo Simmons]

Hi all,

the mobile guy came and got nothing reported. We drove around and tried to trip the warning - no luck. he read some manual info he had access to and pointed to tire pressure and there has been a 1-3 lbs difference at times. I think one of the fronts has a micro slow leak.

After much effort to get to the dealership to try to solve this, I'm here today. There is NOTHING reported in the data - the guy showed me. they are checking it more but the early theory is the same - this is differences in the tires and a few lbs pressure ( never low pressure) .. That is Brand new Michliens on the rear ( that are Michelin Defender LTX M/S, not the Primacy Mich that came on the SUV) and the 2 Primacys on the front with only 20K miles. 1 of the front's has been lower like 33/34 lbs when the others were at 38.

does this sound possible @LokiWolf

 

[duneslider]

I think that is BS too. I have had more than my fair share of leaks and flat tires since owning the expedition and I have had tires much lower than 4-5psi low and have had no issues like this. I really think this is a BS diagnosis. However, if there aren't any active codes present when they are looking at it, I can certainly understand that it would be difficult to diagnose.

At one point, I had 3 tires with half tread and one brand new tire (due to replacement from a flat) and drove it this way for quite a while with no issues.

I will say that I personally am not a fan of completely different sets of tires on the same vehicle but I again doubt this is the issue.

 

[LokiWolf]

Hi all,

the mobile guy came and got nothing reported. We drove around and tried to trip the warning - no luck. he read some manual info he had access to and pointed to tire pressure and there has been a 1-3 lbs difference at times. I think one of the fronts has a micro slow leak.

After much effort to get to the dealership to try to solve this, I'm here today. There is NOTHING reported in the data - the guy showed me. they are checking it more but the early theory is the same - this is differences in the tires and a few lbs pressure ( never low pressure) .. That is Brand new Michliens on the rear ( that are Michelin Defender LTX M/S, not the Primacy Mich that came on the SUV) and the 2 Primacys on the front with only 20K miles. 1 of the front's has been lower like 33/34 lbs when the others were at 38.

does this sound possible @LokiWolf

Yeah, I in agreement with @duneslider. Something else is still going on. Front to back minor size differences shouldn't cause the ELSD to engage. Left to right in the rear "Could", and would be more defined if you were turning(When there is already a differential in speed).

I still think you have a damaged Wheel speed sensor.

 

[Bo Simmons]

@duneslider @LokiWolf - you guys are freaking awsome to keep helping me but I'm in that crap place. Local dealer JC Lewis said they are going to keep my car for 1-3 weeks and then likely say the same thing the guys who were over an hour away in the country (Metter Ga) said today. Given there were no codes other than some stuff that might be related to a small front end accident my wife had with the Cooling Air Dam there were NO codes about the ELSD. More over with more balanced air pressure all within 1 lbs, I drove 70 miles each way to Metter Ford today and never got this ELSD reduced tourqe message showing up. Metter Ford Service seemed to try but I have to give them there is not much to work with.

I'm actually going to switch to 4 Bridgestone Blizzack tires here locally in Savannah GA and drive out to Colorado to work remote for over a month.

So I figure I have a couple of tests to see if ELSD message comes on based on the lower tire pressure and/or having slightly different all season Michilens on the SUV front to back. ( newest are in the back).

1. I can lower the pressure in the front right to say 32 and see if that alone trips this sensor again.
2. As mentioned above I'm about to mount 4 new snow tires and I can see the sensor fails to activate.

I've attached the picture of this warning too so you can see what we see.

My main question is does this feel like any transmission or 4x4 drive train failure that might leave us stranded on the 2000 mile drive from GA to CO? Not holding you to anything - just asking your thoughts since I can not get a good fix on this so far.