Front differential pinion seal leaking

[Imaginary Friend]

I'm beginning to wonder if Ford's axle/diff supplier is using the most fail-prone seals they can possibly source.

The rear axle pinion seal on my F150 is leaking like a sieve at 30K miles, Problem #4 for this truck.

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[TrailDust]

Newest member of the club. 20,000 mile oil change the other night and pinion seal is leaking, no visible drip on the floor as of yet but wet all over with a drop hanging on for dear life at the bottom of the diff. Going to wait till spring to get it in, I fear taking this in for any work with the goobers that staff my selling dealer. ugh.

 

[COHorn]

Add me to the list. Normal driving conditions, 26,900 miles noticed small oil leak on garage floor. Took in to the dealer and the front axcle drive pinion was replaced under warranty within 3 days. Will monitor for any follow-up leaks.

 

[arentas]

New member here, I picked up a BB MT7 with 23.5k miles on it, used. Upon inspection and installing some raptor side steps (a week later) I found the same issue. Front pinion seal is leaking. I made an appointment with my local dealership to address the issue. I will keep up posting. It still has the factory warranty until 8/2025.

Update 3/5/25: got it to the dealer and the part was ordered today arriving tomorrow. Apparently is a common issue per dealer mechanic. Everything was in good condition except for the pinion seal leaking. They expect to install tomorrow.

 

[kevin.gt]

Mine is at the dealer right now waiting for a new pinion seal. I noticed a small spot on the driveway and can see the oil at the bottom of the diff. 29k miles on my 22

 

[ByrdDogX]

I have had to have mine replaced twice and only found after I did my oil change and removing Armor plates.

Recommend everyone check theirs out. Some leak worse than others.

 

[kevin.gt]

I finally got my bronco back. The paperwork says

REPLACED FRONT DIFFERENTIAL PINION SEAL AND TOPPED OFF FLUID IN DIFFERENTIAL

and the line item shows

XY*80W90*QL OIL - REAR AXLE

Looking at the TSB:

To prevent subsequent seal leaks, the front differential fluid must also be replaced using the revised specification Motorcraft® SAE 75W-85 Premium Synthetic Hypoid Gear Lubricant, part number XY 75W85-QL. Refer to WSM section 205-03A > General Procedures > Differential Draining and Filling.

So my question is, should I expect a repeat failed seal in the future?

 

[Exzachly]

I finally got my bronco back. The paperwork says and the line item shows Looking at the TSB:


So my question is, should I expect a repeat failed seal in the future?

The TSB is only applicable to MY 21-22 and some early 23 Bronco builds so I'm assuming Ford fixed this on the later 23-25 models. I'm a Ford service advisor that deals with a lot of Broncos and have not seen any come back for a second repair after performing this TSB.

 

[kevin.gt]

The TSB is only applicable to MY 21-22 and some early 23 Bronco builds so I'm assuming Ford fixed this on the later 23-25 models. I'm a Ford service advisor that deals with a lot of Broncos and have not seen any come back for a second repair after performing this TSB.

Mine's a 22. I bought an ESP so I guess it's not a big deal if it happens again, but a little discouraged that they didn't seem to follow the TSB, at least with how they wrote it up.

 

[Wyld2dr]

I just bought a '23 and on the OASIS they replaced the seal at 8600 miles after 10 months in service (Manufactured 12/22)

 

[Summit981]

Hi All (and Ford Motor Company if you're monitoring this thread), I too am adding myself to this group of owners' who have discovered a Front Differential Seal leak. It was discovered today, 16 May 2025, at my dealership during a service to perform an oil change and to complete manufacturer recall #23S48 (Intermittent rear camera blue/back image on sync screen).

My vehicle is a 2022 Bronco Badlands (non-SAS) with stock wheels/tires/shocks/control arms and axles. I factory ordered this vehicle during COVID and has been just great to own and drive. It's currently at 41K miles on the odometer, almost all of it highway and county road mileage.

During the oil change and vehicle inspection the maintenance technician discovered that the front differential seal had been leaking and showed me the seepage under the assembly and on the skid plate. I previously noted drips in my driveway after previous services but incorrectly assumed it was just engine oil drips following that oil change.

I took these photos for visual reference:

The maintenance tech pointed to the source of the leak, stated it was the front differential seal that was leaking, and that parts were not currently available so would have to be ordered.

My Ford dealership here in Maryland has been great; from the ordering process to them servicing the vehicle. No complaints whatsoever. I hopeful that once the parts needed come in and installed that this will take care of the problem. I'll post a follow-up once that occurs.

 

[Qtip]

Hi, first post here.

22 badlands 30k got my replaced and got my pinion seal replaced due to some oil on the front diff case. Noticed it like others after oil change. Saw residue on case.

The service tech didn’t refill the fluid. They said they just topped it off. Does that sound right? Does this type of repair cause a lot of fluid to leak out like dropping an oil pan?

this is the ticket from the repair. Don’t see anything about refilling the fluid. Should I be concerned for low diff fluid level?

seems the TSB says to replace Fluid.

 

[Ducati1098]

The service tech didn’t refill the fluid. They said they just topped it off. Does that sound right? Does this type of repair cause a lot of fluid to leak out like dropping an oil pan?

this is the ticket from the repair. Don’t see anything about refilling the fluid. Should I be concerned for low diff fluid level?

seems the TSB says to replace Fluid.

I would certainly check it.
Once the seal is removed fluid will come out. Enough to the point that will need to be topped off.
The front differential doesn’t hold a lot, so typically topping it all is all that’s required, but the fact no fluid was charged out on that repair order at all is suspicious

Doesn’t look like they followed the TSB, just replaced the seal

 

[Qtip]

I would certainly check it.
Once the seal is removed fluid will come out. Enough to the point that will need to be topped off.
The front differential doesn’t hold a lot, so typically topping it all is all that’s required, but the fact no fluid was charged out on that repair order at all is suspicious

Doesn’t look like they followed the TSB, just replaced the seal

How should I check it? Should I have service center check? Should I find the TSB and send to my service advisor? Don’t want my differential to blow up for lack of fluid. Thanks for responding so quickly.

 

[Ducati1098]

How should I check it? Should I have service center check? Should I find the TSB and send to my service advisor? Don’t want my differential to blow up for lack of fluid. Thanks for responding so quickly.

Personally, I’d bring it back to whoever replaced the seal and ask them why they didn’t correctly perform the TSB Ford released. Tell them you want the fluid changed.

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