How Much Does It Cost to Replace a Head Gasket

If you have just discovered that your head gasket is failing, you'll next be wondering how much it will cost to have it repaired. We won’t keep you from enjoying the last days of TikTok. The answer to this question of head gasket replacement cost is between $2,000 and $6,000. As always, there are many factors that can impact the price, which we will break down in detail here.

What is a Head Gasket?

So your head gasket is blown. That sounds pretty bad. But, ahh, what is a 'head' anyway, and why does it rely on a gasket? The head referred to in the term 'head gasket' is the cylinder head of your engine. The cylinders are separated from the rest of the engine by a gasket often made of metal or composite material. The gasket that separates these two critical sections of the engine is designed to last the life of your vehicle but often last 20 minutes longer than your powertrain warranty.

Is a Head Gasket the Same as a Valve Cover Gasket?

A head gasket and a valve cover gasket are not the same. The valve cover gasket separates the valve cover from the engine and is less expensive to replace and less likely a possible cause of engine failure.

What Causes a Head Gasket Failure?

Although your head gasket was designed to last the life of the vehicle, a few things can cause it to give up the ghost. The most common reason is overheating caused by some other problem. If the two sections heat up beyond their design temperatures and change shape, the gasket will have a weak area, and pressure can cause it to “blow out.” Hence the term “Blown head gasket.” If this happens, bad things follow.

Then there are the vehicles that just seem to have a lot of head gasket problems. Subaru jumps to mind. If you own a Subaru from a generation or two ago, your mechanic will be well aware of the head gasket’s precarious lease on life. You may be fine. Some people proactively change the head gasket. Others offer up pagan sacrifices to the automotive gods. All are aware the issue exists.

We typed in the term 'head gasket' to the search box over at Car Complaints. Among the complaints, we found one that seems to epitomize the Subaru dilemma.

Jerry F., down in Providence, wrote this about his 2008 Subaru Impreza with 114,000 miles. “I just came from Anchor Subaru, and the technician diagnosed a head gasket leak, oil only at this point, it is leaking pretty significantly. Oil is leaking on the passenger side, and the technician's report strongly suggests immediate repair. $1.979.00 plus tax. Car was well maintained, only two owners.”

The good news for Subaru owners is that the problem is widely known, and the repairs tend to be a bit less expensive than on some other brands’ models.

What Are The Signs of a Leaking Head Gasket?

If your vehicle overheats, always have it checked carefully by a qualified mechanic. She will include a head gasket inspection of sorts in her checklist. You cannot actually see a head gasket by looking into the engine bay, but there are telltale signs.

• If you check your oil and see that the level has gone up, or there is a milky-looking fluid on the stick, remove your oil fill cover and look at it for similar signs of trouble. This is a sign of coolant being where it should not be.
• If your car is leaking oil onto your garage floor, have your car inspected right away.
• If your oil level has been dropping more than usual, have the vehicle inspected.
• If you can see white smoke in your exhaust, have the vehicle checked out.
• Low coolant level.

Poll image courtesy of the Subaru Forester Owner’s Club on Facebook and John Goreham.

How Much Does It Cost To Replace a Head Gasket?

We are using Subaru in the example in this story only because it is a brand which is often associated with head gasket replacement. To find out what folks have actually paid to have a head gasket replaced, we turned to the 50,000-member Subaru Forester Owner’s Group on Facebook. We conducted a simple poll asking how much owners actually paid an independent shop to perform the work. Most owners chose the “$3,000” option in the poll. Although we don't show the rest of the poll answers, the remainder were mostly joke answers. It’s that kind of club. The consensus is the job costs between $1,800 and $3,000 to do correctly.

By “correctly,” we mean that the mechanic took the time to ensure the mating surfaces of the head and block were machined flat. Skipping this step can result in another leak.

How is a Head Gasket Replaced? Can I Do It Myself?

A head gasket replacement is no small job and is not a DIY project. The engine needs to be partially disassembled. In some cases, the engine will be pulled out of the vehicle for ease of access. The mating surfaces are machined flat by a specialist. This step is referred to as “decking” by those in the business. A new gasket is installed, and the whole shebang is reassembled. Some vehicles have two head gaskets, left and right, in the case of the Subaru engine.

Who Can Replace My Head Gasket?

An experienced mechanic in a fully-outfitted shop can replace your head gasket. This is a job we would only trust a dealer or a professional, trusted shop to perform. It’s not a job for discount auto repair chains, and we would not suggest trying a new shop you have not grown to trust.

The dealer’s cost will likely be a bit higher. However, Subaru mechanics and shops we have spoken to say they can actually offer a competitive price because they have done so many that they have learned how to do it right and also efficiently. If you can, shop around for the best price and talk to the mechanic.

Should I Replace My Head Gasket, Replace the Engine, Live With It, or Junk the Vehicle?

Many owners weigh installing a rebuilt engine instead of replacing a head gasket. Others will commit to the new head gasket job and then add in critical maintenance such as a timing belt, thermostat, spark plug, and fuel pump replacement. At this point, the job is approaching $4,000, and in the case of a well-worn vehicle, possibly the value of the vehicle. If you opt to recycle the vehicle, why not donate it to Car Talk’s NPR network? Here’s how.

What About The Quick Fix?

There is one quick fix possible if your vehicle is on its last legs and you just need to get through the last half of winter before the vehicle is recycled. You can purchase a can of spray stuff that you put into the engine to stop the leak. It works sometimes. Sometimes not. Never for good. If you are thinking about just junking the car, this is well worth a try. If you plan to keep the car, do not use this stuff.

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