What You Need to Know About Buying a Subaru Engine

Subaru boasts that its customers love their Subarus. I agree with them, since over the years I have seen Subaru owners fix vehicles that the owners of other brands wouldn't have even considered fixing. In many cases, this is justified since a running Subaru maintains a higher resale value than other vehicles of similar age. Engine failure is the most expensive mechanical job a Subaru owner can face, and I've gotten a number of questions over the years about the best ways to go about replacing different Subaru engines.

The Subaru Legacy Engine

The Subaru Legacy engine is perhaps the most commonly repowered Subaru vehicle. Beginning in 1996, this vehicle was powered with the 4 cylinder, 2.5L EJ25 Subaru Legacy engine. While the EJ25 has undergone many changes over the years, it has been faced with one consistent source of failure: overheating. This isn't the fault of the engine, but rather the fault of the cooling system supporting the engine. With its wide bore and short stroke, this just isn't a very heavy engine – there is no way for it to absorb any heat if the radiator, cooling fan, or water pump don't do their job perfectly.

On 1996-1998 Subaru Legacys, I recommend you seek out a JDM (Japanese Domestic Market Engine) from a company that offers at least a 9 month warranty. On later model Legacies, you will want to seek out a good used engine with low miles from a wreck, preferably from a company that provides a vehicle history report to verify the miles. The engine should be carefully inspected to ensure that no damage has occurred to the timing cover, which is very brittle and can easily damage cam and timing gears. Many of these engines have been cheaply repaired with used, high mileage heads, and simply aren't the long term solution you're looking for. There are a few specialty Subaru rebuilding companies, but you will probably spend more money than is prudent at one of these places.

The Subaru Forester Engine

Introduced in 1998, the Forester has also used the 2.5L EJ25 engine with great success. The high performance boxer has allowed the Subaru Forester engine to maintain a low weight, compact, high performance engine – the best in its sparsely populated class. In 1999, the Forester switched to primarily putting SOHC heads on the EJ25. This was the first SOHC Subaru Forester engine, and in 2000 the DOHC was dropped completely. The SOHC served along faithfully until 2004, when a DOHC turbo engine (the EJ255B series) came out. The DOHC engine is not only more powerful (210 horsepower vs the 165 hp of the SOHC engine), but more reliable.

On 1998-1999 DOHC Foresters, you should again seek out a JDM. Your buying strategy on later model engines should again be to find a low mile used engine from a wrecked vehicle.

The Subaru Tribeca Engine

The Subaru Tribeca engine is the latest in a long line of Subarus. Bigger than the Forester or Legacy, it was introduced originally with a 3.0L engine, the EZ30. In 2008, the 3.6L EZ36 was introduced. It gained 11 horsepower over its 3.0L counterpart. Neither of these engines is currently available through JDM suppliers, and this author doubts they will ever be. Your best best is to purchase a replacement engine from a wrecked vehicle.

When searching for an engine supplier, you should keep in mind that there are good suppliers, and bad suppliers – and everything in between. You're not looking for a friend, but someone with the engine you need in the condition you need it in. Make sure you investigate the company's history thoroughly if you haven't done business with them before. You should look for a positive rating from the Better Business Bureau. A lot of people don't realize you should also be looking to deal with a company that provides a free vehicle history report with each engine that they sell. This report isn't specific to the motor, but rather verifies the miles on the vehicle the engine is from at the time of the wreck that took it off the road.