2017 Low Speed Vibration

[WhoaTed]

Hello all, I’ve found answers to other questions on the forums but I haven’t found any advice on the following; 2017 Platinum EL 4x4, 147,000 miles:

Especially after cold start, when moving either forward or reverse, in gear, moving slowly 1-10mph with wheel turned left or right there’s a heavy binding sound/feel coming from the drivetrain; very little if any thru the steering wheel. Once it’s moving the sound/feel stops if I take it out of gear while it continues to slowly roll, returns if I put it back in gear. Straighten the wheel, it goes away. Nothing at higher speed.

This has been happening since I bought it 15,000 miles ago, dealer thought it was hub actuators. Does feel a bit like it, but doesn’t change at all when AWD is actuated but I replaced them anyway having done it before; I only mention it for reference, it’s not the problem. AWD on/off including low doesn’t affect it, it does resemble the normal 4x4 low binding but the binding doesn’t increase the more it moves and again, only while turning. Again, The front hubs work fine, they are not engaged.

Butt feel tells me it’s coming from near the front of the driveshaft/transfer case/transmission area; all have proper clean fluid & good u-joints. I’m very good at mechanical diagnostics & know which end of the wrench goes on the nut, I can usually figure this stuff out but this one is laughing at me. Anyone?

 

[losttime1]

I had the same issue it seems. It wound up being the clutches in the rear differential. Ford replaced the fluid with a product that had "better stiction". It's better, but not perfect. Good luck!

 

[WhoaTed]

I had the same issue it seems. It wound up being the clutches in the rear differential. Ford replaced the fluid with a product that had "better stiction". It's better, but not perfect. Good luck!

Thank you, that crossed my mind. The rear diff was dealer-replaced @88k (currently 145k), the very reputable dealer is in the middle of nowhere in S Dakota & cared for the car since new. Could be that incorrect fluid was used at that time & now it’s breaking down & causing issues with the limited slip. I’ll change it this weekend, anyone know offhand what the proper fluid is or recommend an upgrade?

 

[WhoaTed]

Thank you, that crossed my mind. The rear diff was dealer-replaced @88k (currently 145k), the very reputable dealer is in the middle of nowhere in S Dakota & cared for the car since new. Could be that incorrect fluid was used at that time & now it’s breaking down & causing issues with the limited slip. I’ll change it this weekend, anyone know offhand what the proper fluid is or recommend an upgrade?

wanted to follow up after I found the issue. Losttime was correct, diff clutch pack is worn: LSD is still working, so started by changing the fluid (a very little sludge from clutch pack material), huzzah no more noise/shuddering…for about a week. It started to act up again, changed fluid again to see what it looked like (clean), everything else in the diff is in good condition, teeth marks are all as they should be. Shudders intermittently on slow turns. Needs the packs replaced, oh well.

Looks like the pumpkin has to come out to service the clutches, haven’t found an answer yet showing otherwise. Not the end of the world, but would be easier to do it in situ.

I have a multi-bit screwdriver & a hammer, I’m good either way.

 

[losttime1]

I have very low mileage on my 2017 Expedition., about 55,000 mi. If I remember correctly, the dealership mechanic said this was the only year they used this particular rear. The vehicle was under an extended warranty. He just changed the fluid with a lube that has more stiction. I can say that I no longer have the vibration issue. It was only prevalent when doing sharp low-speed turns, like leaving from a curb.

 

[WhoaTed]

I have very low mileage on my 2017 Expedition., about 55,000 mi. If I remember correctly, the dealership mechanic said this was the only year they used this particular rear. The vehicle was under an extended warranty. He just changed the fluid with a lube that has more stiction. I can say that I no longer have the vibration issue. It was only prevalent when doing sharp low-speed turns, like leaving from a curb.

Interesting re: diff unique to 2017. I bought mine w/135,000 miles on it, complete dealer records from new were included (SMALL town in S Dakota). Shows that there were vibration complaints starting @79,000 miles, then diff was replaced @84,000. No complaints since (until now, ha), like you it does it on very low speed turns parking lots etc. Clutch packs only good for 80,000 miles? I wonder if clutch packs are the only difference from other years…