Dozens of new Ford Bronco owners have reported critical issues with their trucks’ 2.7-liter EcoBoost V6 engine. They fail with low mileage—under 10,000, it seems—and are sent to dealerships where repairs can take months. The whisper of this problem first hit Bronco6G forum in July 2021, although the thread noting owner testimony has grown to include the 46 off-roaders affected at the time of publication.
With the list growing week by week, Drive contact Ford for comment. A spokesperson from the automaker explained, “We are aware of a specific number of engines with this issue and we are investigating. If any customer encounters a problem, they will be covered by the vehicle’s 5-year 60,000-mile powertrain warranty.”
This confirms that Ford at least acknowledged the situation. But what should a Bronco owner look for?
The first user-reported issue involved a Bronco with 1,146 miles on the odometer, and it ended up being linked to a dropped valve—that means the head of one of the engine valves separated from the stem and ended up falling into the cylinder. This immediately results in a loss of compression, but also sends a piece of metal into the cylinder which can lead to disastrous results.
To be clear, the motor we’re talking about here is Ford’s second-generation 2.7-liter EcoBoost. Currently, it’s only found on the Ford Bronco and F-150, but most failure reports are limited to the Bronco; some F-150 owners have reported failures as well, but it was significantly less common during our research into the matter. The first-generation 2.7-liter is still used in some Ford and Lincoln vehicles, though it doesn’t appear to be affected.
The forums remained relatively quiet for several months after the first report, but in October, more threads of failed engines started popping up. Other owners chimed in over the following months, many of them noting that their Broncos had also dropped valves, resulting in engine replacements.
Besides that Bronco6G In the thread, which also describes the complaints seen in various Facebook groups, there are several Reddit threads that suggest Broncos equipped with 2.7 liters are suspected of suffering from the same problem. A member posted a Facebook screenshot of someone noting that a dedicated Facebook group for technicians had seen about 30 Bronco engine failures in the space of a month.
The National Highway Traffic Safety Administration also has a number of complaints about the Bronco on its website. Of the 42 complaints recorded, more than half involve SUV engines. A staggering 20 out of 25 engine-based complaints refer to complete failure, many specifically pointing to problems resulting from falling valves.
In October 2021, now deleted Bronco6G The account posted that the failure was caused by a bad batch of valves Ford received from one of its suppliers. The account claims to work at the Lima engine plant where 2.7 liters are produced and notes that the faulty valves were mostly in the April batch. Users stated that something in the metal composition of the valves became brittle due to engine heat over time, and emphasized that it was a supplier problem.
Interestingly, a note in Ford’s January 2022 “State of the Plant” newsletter for the Lima facility noted that the supplier issue was resolved with its Nano engine—the 2.7-liter one found in the Bronco. More specifically, it mentions a more robust valve design and material change, which is similar to a post from a deleted user on Bronco6G.
It’s hard to say how many Broncos might be affected, as the build date of the included engine seems to last months rather than weeks. For example, the thread on Bronco6G the failure tracker also tracks the manufacturing date of the failed engine, which ranges from May 2021 to October 2021. Ford sold more than 20,000 Broncos in the US and Canada during that timeframe, though the pickup rate was at the 2.7-liter V6 vs. the 2.3-liter. liter four cylinder not available. It’s unclear whether the April batch valves were in use until October 2021, or whether claims from Lima employees were holding back water. The highest mileage on the reported failure was 6,986 miles, while the lowest was just 984 miles.
Some of the affected owners reported that they were compensated with a longer powertrain warranty, and others commended Ford for the way they handled the issue by working closely with affected customers despite the long repair time. However, some want broader action taken to protect other owners from potential failures by asking the NHTSA Disability Investigation Office to open an investigation into the failure.
Whether a defect investigation is opened or not on this matter, this could be a major flaw in Ford’s flagship product. After all, catastrophic engine failures weren’t like minor component failures—it was the heart of a vehicle, and a fairly expensive system of parts to replace at the time. People in Bronco6G asks affected owners to file a complaint with NHTSA if their machine fails in the same way and suggests reporting the problem to users tracking the failure on its forums.
Have a tip or question for the author? Contact them directly: email@example.com