Nissan Forester Oil Consumption Burning Fix: Causes and Solutions

If you've noticed your Subaru Forester burning through oil faster than it should, you're not alone. Excessive oil consumption is one of the most reported issues among Forester owners, especially those with the 2.5-liter boxer engine. Finding the right Nissan Forester oil consumption burning fix (often searched when people mean the Subaru Forester) can save you from costly engine damage, roadside breakdowns, and the frustration of constantly topping off your oil between changes. This guide walks you through exactly what causes the problem, how to fix it, and what to watch out for along the way.

What Does It Mean When a Forester Burns Oil?

Oil burning happens when engine oil slips past the piston rings or valve stem seals and enters the combustion chamber, where it gets ignited along with fuel. You might notice blue smoke from the exhaust, a burning smell, or find yourself adding a quart of oil every 1,000 miles or less. Subaru considers oil consumption "normal" up to a certain point, but many Forester owners report usage well beyond that threshold.

The EJ25 engine found in many Forester model years is especially known for this issue. If you want to dig deeper into the root causes, we break them down in our article on what causes EJ25 oil consumption and how to address it.

Why Is My Forester Burning Oil So Fast?

Several factors can cause your Forester to consume oil at an abnormal rate. Here are the most common ones:

Worn piston rings Over time, the rings that seal the combustion chamber lose their ability to keep oil out. This is the number one culprit in high-mileage Foresters.
Damaged valve stem seals These small rubber seals harden and crack with age, letting oil drip into the cylinders.
Low-quality or wrong viscosity oil Using oil that doesn't match Subaru's specifications can speed up consumption.
Infrequent oil changes Sludge buildup from old oil can clog passages and increase wear on internal components.
PCV valve failure A stuck positive crankcase ventilation valve can increase pressure in the crankcase, forcing oil past seals.
Manufacturing tolerances Some EJ25 engines were built with tighter piston ring gaps that contributed to higher oil usage from the factory.

If you're seeing excessive oil usage between oil changes, our breakdown of why Foresters use so much oil between services covers this in more detail.

Which Forester Model Years Have the Worst Oil Consumption?

While oil burning can happen in any vehicle, certain Forester model years are more prone to it:

2011–2014 Forester 2.5L These years are heavily reported on owner forums and in NHTSA complaints for burning a quart every 1,000–1,200 miles.
2006–2010 Forester 2.5L The naturally aspirated EJ25 in these models is known for ring and seal wear at higher mileage.
2015–2018 Forester 2.5L (FB25 engine) While improved, some owners still report abnormal consumption, particularly in the first few model years of the FB series.

Subaru even issued a technical service bulletin acknowledging excessive oil consumption in certain 2011–2014 models, offering extended warranty coverage for engine short block replacement in some cases.

How Can I Fix Oil Burning in My Forester?

The right fix depends on the severity and cause of the problem. Here are the most effective options, ranked from least to most involved:

1. Switch to a Higher-Viscosity Oil

If you're running 0W-20 as Subaru recommends, stepping up to 5W-30 can reduce oil consumption in some engines. The slightly thicker oil is harder for worn rings to push past. This won't fix a mechanical failure, but it can slow the rate of loss noticeably. Always check your owner's manual and consider your climate before switching.

2. Replace the PCV Valve

A failed PCV valve is cheap to replace usually under $20 for the part and can make a significant difference. If the valve is stuck open, crankcase pressure drops too low and oil gets pulled into the intake. If it's stuck closed, pressure builds and pushes oil past seals. Either way, it's a quick fix worth trying early.

3. Use an Oil Additive or Engine Treatment

Products like Restore or Liqui Moly Motor Oil Saver are designed to condition seals and reduce oil burning. Results vary, and they're not a permanent fix for serious mechanical wear, but some owners report a 30–50% reduction in consumption. Use them as a band-aid, not a cure.

4. Replace Valve Stem Seals

If the seals are the main issue, replacing them can significantly reduce oil burning. This is a moderate-cost repair typically $500–$1,200 depending on labor rates and doesn't require full engine disassembly.

5. Install New Piston Rings (Engine Rebuild)

For severely worn rings, the real fix is an engine teardown and new piston rings. This is the most expensive option ($2,000–$4,000+), but it's the only solution that truly restores the engine. Some owners opt for a used or remanufactured engine instead, which can sometimes be more cost-effective.

6. Subaru Short Block Replacement

For eligible vehicles under the extended warranty or TSB coverage, Subaru may replace the short block at no cost or reduced cost. Check with your dealer using your VIN to see if your Forester qualifies.

Knowing your engine's exact oil capacity and specifications helps when choosing the right oil and tracking how much you're actually losing between changes.

What Mistakes Do Owners Make When Dealing With Oil Burning?

Here are the most common missteps that can make the problem worse or waste money:

Ignoring the problem Running an engine low on oil causes catastrophic damage. If you're adding oil frequently, monitor it closely.
Overfilling the crankcase Adding too much oil creates its own problems, including increased pressure, seal leaks, and catalytic converter damage.
Using the wrong oil weight blindly Jumping to 10W-40 or heavier oil without understanding the implications can hurt fuel economy and cold-start protection.
Skipping the PCV valve check It's cheap, easy, and often overlooked. A $15 part can save you a $3,000 engine rebuild.
Assuming all oil burning requires an engine rebuild Many cases can be managed with simpler fixes like seal replacement or oil changes.
Not documenting oil loss If you're pursuing warranty coverage or a TSB claim, you need records showing how much oil you're adding and how often.

How Do I Monitor Oil Consumption Accurately?

Tracking oil loss is the first step toward finding the right fix. Here's how to do it properly:

Start with a fresh oil change using the correct grade and amount.
Check the oil level at the same time every day ideally when the engine is cold and on level ground.
Record the dipstick reading and note how many miles you've driven since the oil change.
When the level drops to the low mark, measure exactly how much oil you add to bring it back to full.
Calculate your consumption rate: quarts added per miles driven.

If you're adding more than one quart every 1,200 miles, that's considered excessive by most standards and worth addressing immediately.

Can I Keep Driving a Forester That Burns Oil?

Yes, but with caution. Many Foresters run for tens of thousands of miles while burning oil as long as you stay on top of the level. Keep a quart of the right oil in your trunk at all times. Check the dipstick every fuel fill-up. And don't wait for the oil pressure light to come on by that point, damage may already be happening.

That said, oil burning tends to get worse over time, not better. What's a quart every 2,000 miles now may become a quart every 800 miles in six months. Addressing the root cause early usually costs less than waiting until the engine is damaged.

What Should I Check Right Now?

Here's a practical checklist to start diagnosing and managing your Forester's oil consumption today:

Check your oil level Do it now, while the engine is cold and parked on flat ground.
Look for blue smoke Have someone rev the engine while you watch the exhaust. Blue-gray smoke means oil is burning.
Inspect for external leaks Look under the car for oil spots on the ground. Check the valve cover gaskets, oil pan, and drain plug.
Replace the PCV valve It's a 10-minute job on most Foresters and costs almost nothing.
Start tracking consumption Use the measurement method above to establish your baseline.
Check for TSB or warranty eligibility Contact your Subaru dealer with your VIN.
Choose the right oil Consider stepping up one viscosity grade if your engine is showing wear signs.

Dealing with oil burning isn't fun, but it's manageable when you understand what's happening and take action before it gets worse. Start with the simple checks, keep records, and don't let anyone tell you a full engine rebuild is your only option it rarely is. And if you ever need to reference your engine's specific oil specs, our Forester 2.5 oil capacity guide has all the numbers you need.