2020-2024 Subaru Outback 2.5L Engine (FB25D): Longevity, Problems, and Specs

Subaru vehicles are known for their unwavering capability, which is due to the expert engineering that underpins them. The Japanese brand's unique always-on Symmetrical All-Wheel Drive (SAWD) system has been the foundation of its vehicles for decades. Continuing its maker's 69 years of legacy is the Outback SUV, which has always been known for its high-mileage capability, resiliency, and overall versatility that can accommodate any lifestyle.

One of the signature boxer engines of Subaru that made it to the Outback is the 2.5L engine with the designation FB25. The FB-series comes in as the successor of the famous or infamous EJ25-depending on whose side of the story you're on.

The engine promises better responsiveness at low torques, better fuel economy, and overall performance than its predecessor. So, in this article, we will see whether it does live up to expectations or it inherited some of the major problems that plagued its precursor.

Key features and my opinion about the engine

• Production years:2018-now
• Average lifespan of FB25D:170,000-190,000 miles
• Fuel supply type:direct injection
• Power range:182 hp
• Fuel efficiency:good
• Engine block material:aluminum
• Engine reliability score:medium
• The most common problems:carbon buildup on intake valves, oil consumption due to ring wear, oil leaks, no lifters.

Key Specs of the 2022 Subaru Outback 2.5L Engine

The 2.5L FB25D engine used by the 2022 Subaru Outback is packaged with a flat-four engine, also commonly referred to as a boxer-four engine due to its layout. In general, the boxer-four layout leverages from its minimal vibration, a low center of gravity, and a short engine length. These present efficiency in air cooling because of the airflow distributed evenly across the four cylinders.

For its application in the Subaru Outback, the Boxer engine's smaller size, as well as its all-aluminum construction, reduces the engine's weight. As a result, acceleration is faster and the ride is more enjoyable. The vehicle's lighter weight improves fuel efficiency, too.

The displacement of the engine sits at 2,498 cc and it uses natural aspiration, making it more effective in moving more air and fuel, allowing it to produce more power. It has a bore of 94 mm and a stroke of 90 mm to put a balance between engine rev and fuel economy. These contribute to a compression ratio of 12.5:1 which allow an engine to optimize the extraction of mechanical energy from the combustion process while keeping fuel economy and emissions in check.

In addition, the engine features a dual-overhead camshaft (DOHC) with four valves per cylinder and utilizes an active valve control system (AVCS). The DOHC configuration further guarantees better airflow at high engine operations and the AVCS complements this with its enhanced scavenging effect that brings about more efficiency and fuel economy, especially during high engine loads. Meanwhile, the fuel system is managed via a gasoline direct injection system for precision in the delivery of the right air and fuel ratio to the engine.

Overall, the 2.5L flat-four of the 2022 Outback is capable of producing up to 182 hp at 5,800 rpm and 176 lb-ft of torque at 4,400 rpm. Its fuel economy is rated by EPA at 26 mpg for city drives, 33 mpg on the highway, and 29 mpg combined.

Durability of the 2022 Subaru Outback 2.5L Engine

Surprisingly, the Subaru 2.5 engine can rake a total mileage between 180,000 and 190,000 miles before requiring significant auto maintenance or repair. Given that the average driver travels around 14,000 miles per year, a Subaru 2.5 engine could potentially last for more than two decades.

That means regular maintenance and prevention of the problems that it is known for before they get any worse. Likewise, it should be driven with care and must be well-oil at all times.

Most Common Problems in the 2022 Subaru Outback 2.5L Engine

There are many potential problems that may happen to an engine despite its durability. This can be due to a lot of factors such as manufacturing defects, poor maintenance, bad driving habits, and harsh environmental conditions that the vehicle is frequently exposed to, among others.

The frequency of problems in the 2022 Subaru Outback 2.5L engine is quite low but there are some issues that stand out based on the number of complaints associated with them. These include the following:

1. Timing Chain Premature Wear

A timing chain ensures proper timing by synchronizing the rotation of the crankshaft and camshaft(s) and allowing the engine's valves to open and close during each cylinder's firing. Because the chain is located inside the engine and must be lubricated by the engine oil, oil maintenance is also essential.

Compared to a timing belt, a chain drive can last as long as the entire usable life of the engine. However, based on the recall announcement of Subaru not so long ago, the timing chain of the 2.5L boxer engine has the potential to break due to a manufacturing defect.

There are three main symptoms that could indicate a problem with the timing chain. The first is a rattling noise coming from the engine caused by the loose parts of the chain hitting each other or against other components. The second is an engine misfire if the timing chain is stretched. The third is the dreaded Check Engine Light.

If you notice any of these symptoms, it's important to take your car to a mechanic and have it checked as soon as possible. Ignoring the problem can lead to more serious engine damage.

If the timing chain is indeed the problem, it will need to be replaced. The cost of replacement will depend on the make and model of your car, but it's usually not a cheap repair. Subaru, for example, charges around $1,000 to $2,500 for timing chain replacement parts and labor. On the other hand, there may be times when it only needs recalibration, so you may only be charged based on the labor done by your mechanic.

The best way to save from this potentially expensive repair is by taking advantage of your vehicle warranty. If this is indeed caused by a manufacturing defect, you may be able to avail yourself of free repair or replacement of the component.

2. CVT Problems

The application of continuously variable transmission (CVT) in vehicles is no longer new. Although it presents a lot of benefits in terms of responsiveness, fuel efficiency, better torque ratio, and easier design on the part of the manufacturer, it is still plagued by plenty of problems. The 2022 Subaru Outback is no stranger to this and a recall by its maker also acknowledged such an issue.

The transmission is technically separate from the engine, but it does have a major effect on how the power unit of your vehicle operates. A malfunctioning transmission is bad news for the engine in more ways than one. It can force the engine to rev up higher than usual, which can lead to damaging wear and tear on the engine components. The engine might also operate less efficiently, thereby guzzling more fuel in the process.

The first sign that there might be something wrong with the CVT of your Outback is often an abnormal noise coming from the transmission area. This can be accompanied by a feeling of jerking or slipping when shifting gears, as well as delayed engagement of the drivetrain when you step on the gas pedal.

If you experience any of these, it is best to have your Outback checked by a qualified mechanic as soon as possible. The earlier the problem is diagnosed, the easier and less expensive it will be to fix. The replacement cost for the CVT of the 2022 Outback can drive you around $7,500 and $8,600 for the parts and labor.

Again, since this has been a part of a recent recall announcement, you may apply your warranty for a defect on this part to get the problem solved immediately.

3. Electrical Problems

Another major cause of concern in the 2022 Subaru Outback is its various electrical issues. The most common of them is battery failure, which can happen even if it's not yet due for its recommended replacement.

The automaker is yet to pinpoint the exact cause of the problem. However, one possibility-if the battery has no defect or the issue seems to occur frequently even if the battery is still relatively new-is there might be problems in the vehicle's charging system.

Since the charging system is made up of many parts, your mechanic may have to check the battery, alternator, and voltage regulator for any signs of damage or shorting. Furthermore, the wirings, connectors, terminals, sensors, fuses, spark plugs, and control modules, among others, will also have to be tested for their quality, and any malfunctioning part should be replaced immediately.

Conclusion

There remain a lot of reservations from buyers when it comes to the 2022 Subaru Outback 2.5L engine. This is primarily due to the bad reputation left behind by its predecessor, the 2.5L EJ25 engine, which was marred by its high maintenance costs stemming from defects due to specific design choices by the automaker.

However, in reality, the new 2.5L FB25D engine boasts a lot of improvements over its predecessor and is more than capable of delivering optimum performance, fuel economy, and reliability.