Rear end Puked on Expedition.

[Deadman]

Well, damn.

I've been trying to pinpoint a problem I’ve been noticing. And now I’m convinced it’s this one.

Deadman, were your symptoms only in 4A? Or also in 2 and 4 locked.
Could you feel some light “stumbling” in the drivetrain under light acceleration?

I never used 4A or locked much. It just always did it from a stop on very light acceleration. It was just a small shudder at first and then it grew to a horrible shudder. Its worse of slopes, angles, hills, etc. Always need to stop and then when I take off slowly it would shudder. It was so bad that it was locking up and squealing the inside rear tire in some tight parking lots.

 

[NukeLife]

Mine is exhibiting a shudder also. Most noticeable on light acceleration form a start or at low speeds in town. But also more noticeable when going up a steep grade, even at highway speeds.
Very noticeable when towing. Thought I had a problem with my ball hitch it was so bad.

 

[Soliyou]

The differentials in these things aren’t made to last. I changed the rear diff fluid at 18k miles while troubleshooting a whine above 75 mph. The fluid looked very strange. It didn’t have noticeable metal shavings but the fluid looked like a pool of dark brown paint mixed with silver paint.

I changed the fluid and added the friction modifier but the noise is still present.

There are also many cases of front diff failure on the F150 with the same transfer case. My front diff is very noisy too.

 

[wakeboarder]

The fluid looked very strange. It didn’t have noticeable metal shavings but the fluid looked like a pool of dark brown paint mixed with silver paint.

There is a specific note about the fluid color in the service manual. It said something along the lines of the white being normal due to assembly lubricant.

update:
I found it.
“Axle Fluid Analysis
The appearance of milky or gray axle fluid in early mileage axles is a result of white marking
compound used at the assembly plant to verify gear mesh contact pattern. The marking compound
within the fluid will darken some over time. The milky fluid appearance will diminish and cause no
harm and does not require a fluid change.”

 

[Soliyou]

There is a specific note about the fluid color in the service manual. It said something along the lines of the white being normal due to assembly lubricant.

update:
I found it.
“Axle Fluid Analysis
The appearance of milky or gray axle fluid in early mileage axles is a result of white marking
compound used at the assembly plant to verify gear mesh contact pattern. The marking compound
within the fluid will darken some over time. The milky fluid appearance will diminish and cause no
harm and does not require a fluid change.”

yeah, I am familiar with this grey color. Mine was like silver paint. I attributed this to break in metals and will check it again in 2000 miles.

 

[simmons351w]

I'm glad I am not the only one. It took 2 visits to confirm I wasn't full of it and find the problem area and 2 more visits to the dealership to get to a into the rear end guts replacement only to realize a part or a tool was missing. I've been waiting for 3weeks for that last tool to arrive to get it done.

My symptoms were a shutter when turning, especially uphill and right after towing on a '19 with the HD tow and 28kmiles. The dealership did however figure out that if you unplug the elsd, all of the problems go away and nothing gets worse. You will get an alarm message everytime you start but that's better than wondering when it is going to give out

Sent from my Pixel 2 XL using Tapatalk

 

[Deadman]

I'm glad I am not the only one. It took 2 visits to confirm I wasn't full of it and find the problem area and 2 more visits to the dealership to get to a into the rear end guts replacement only to realize a part or a tool was missing. I've been waiting for 3weeks for that last tool to arrive to get it done.

My symptoms were a shutter when turning, especially uphill and right after towing on a '19 with the HD tow and 28kmiles. The dealership did however figure out that if you unplug the elsd, all of the problems go away and nothing gets worse. You will get an alarm message everytime you start but that's better than wondering when it is going to give out

Sent from my Pixel 2 XL using Tapatalk

My "KIT" was also missing bolts. The parts list showed the bolts included, but they weren't. They waited 2 more days for the stupid bolts.

Heres the thing.... The service guys told me they specifically DON"T KNOW WHY it failed, and they put all the same parts back in it, so its probably gonna fail again because there was nothing updated. Ford tells them to just replace all of the internals, so they don't really expect it to be fixed as the root problem really was NOT addressed.
Whatever, thats what the 8year 125K warranty is for! lol.

 

[jddotson]

I have a 2019 in the shop right now with the exact same problem...rear differential binding up.

 

[Deadman]

Looks like I started a soon to be long list of these failures.......

 

[wakeboarder]

Looks like I started a soon to be long list of these failures.......

I hope not! I also hope it is something that only shows up on the 4X4’s.