Long-Term Ford Bronco Update: A Leaky Differential and Long Waits for Service

• Our long-term Ford Bronco leaked differential oil all over my sister-in-law’s driveway.
• Getting an appointment for service took a relatively long time.
• In total, the Bronco spent eight days in the shop, and the repair was covered under the warranty.

The first thing I did when I saw the spots in the driveway was swear. Next, I rubbed some of the fluid between my fingers and gave it a sniff, and it was clearly some sort of oil, not coolant or anything else. I checked the Bronco’s oil (which is a PITA, let me tell you: That dipstick is hard to reach, and you have to guide it back in with both hands). The oil level looked fine, so the next step was crawling under the car.

Yup, that's a leak

As much as our Bronco’s ride height makes it a pain to reach the dipstick, my XL torso could slide pretty easily under the truck without any sort of jack. What I saw was a bit shocking: An oil stain extended back from where the front differential peeks through the skid plate. The oil had migrated to parts of the front suspension and other underbody components.

Some had even blown back far enough to build up on the frame braces that attach to the center differential shield. There was enough that I was able to spot droplets forming.

Talking with our Senior Manager of Vehicle Testing Operations Mike Schmidt and Associate Manager of Vehicle Testing Operations Rex Tokeshi-Torres, we came to the conclusion that the leak was most likely coming from the front differential, and oil had been blown back along the underside of the vehicle during my drive.

A brief search of some forums indicated that quite a few Bronco owners had issues with leaky differentials and axles, but there was enough range to the issues being reported that it didn’t really give us a lot of confidence in our diagnosis.

So I set about trying to find a Ford dealership that could look at the vehicle and, hopefully, properly diagnose and address the problem.

Beat by the Christmas rush

In the days just before and after Christmas, I called six dealerships in a 35-mile radius. Five told me they didn’t have any open appointments for anywhere from two weeks to one month. The last one said I could drop the Bronco off in just a few days, but after I dropped it off it would need at least six more days before it could diagnose the vehicle. Meanwhile, the piece of cardboard I’d slid under the Bronco continued to accumulate drops of oil, albeit more slowly while it wasn’t being driven.

I was left with the decision of whether to bundle my family back into a leaky Bronco and drive almost 400 miles or continue our occupation of my sister-in-law’s den for at least another week.

In the end, we decided to drive back to LA. The logic was this:

1. The leak didn’t seem to be engine oil; it was most likely the front differential.

2. When in 2WD mode, the front driveshaft doesn’t spin so, theoretically, even if there was no oil at all in the differential, so long as I didn’t engage 4WD there shouldn’t be any damage to the components or risk of breakdown.

Thankfully, our drive home was utterly uneventful, aside from a bit of traffic, and we arrived safely in LA where the Bronco set about staining its second driveway.

We get our diagnosis and repair

On December 29, Rex and I called local dealerships to try to get an appointment. The largest Ford dealership in my area told me that because of the size of its backlog it had completely closed its appointment books. Another dealer told Rex that it had six Broncos in line for work already, and it would be at least two weeks before it could look at ours.

The dealership from which we originally bought our Bronco told us that it wasn’t making appointments because it was operating on a “first come, first served” basis, but the dealer could take the Bronco if we dropped it off that day by 3.

Upon drop-off, we were informed the dealer would need up to a week for diagnosis and that there was an open recall on our Bronco for the child safety locks — faulty locks could allow the rear passenger-side door to be opened from inside the vehicle even when set to “on.” Parents who own 2021-2022 Broncos should check their VINs.

Six days later, the dealer called to tell us that the safety lock recall had been addressed and that the leak was coming from the pinion seal (where the driveshaft enters the differential) on the front differential.

The folks there managed to source the replacement seal quickly, and the Bronco was fixed and ready for pickup two days later. In total, our Bronco spent eight days in the shop. The repair was covered under warranty, so the cost to us was zero. Once we finally got to the head of a queue, it seems like the issue was straightforward to address.

I went back to the forums with this diagnosis and confirmed we’re not the only ones who have experienced it, although it’s hard to say how widespread the problem is. What struck me as notable is that more than a few owners reported they wouldn’t be driving their vehicle at all until they could get a fix, and a few cited long waits for parts but not for appointments.

Nobody likes waiting

When attempting to set up the initial appointment, I was repeatedly told by dealers that I wouldn’t get answers for up to a month. When I voiced concerns about this being a potential drivability issue, I was told that cars were prioritized by the order they came in and not by severity of the issue. I appreciate the democratic approach, but, especially considering my situation, I would have appreciated a quick diagnosis to get a professional thumbs up or down on driving the Bronco home even more.

If I were an owner who’d dropped luxury-car money on a Bronco, and maybe even paid a big premium in dealership markups, I’d be a lot more frustrated with the long wait and the lack of any alternatives. The truck is under warranty, so I don’t think it would be unreasonable for an owner to expect a loaner or rental if the vehicle is out of commission awaiting service through no fault of the owner. And I can’t imagine how someone who dropped potentially $100,000 on an F-150 Lightning Platinum would feel.

For that kind of money, there are brands that will come pick your vehicle up from you and leave a loaner at your door.

Edmunds says

We suspected we might encounter some teething issues with our first-model-year Ford Bronco, but on the whole, the bugs and faults we’ve encountered have been relatively minor. This differential leak is the most severe problem we’ve had, and based on forum responses we’re not alone. Hopefully Ford will iron this issue out for newer model years. We’ll chalk the long waits for service appointments up to the Christmas holiday and report if we encounter them again in the future, but considering the stress and travel needs of the season, it's the kind of thing that could leave a sour taste in an owner’s mouth.