2003 Subaru Outback Head Gasket Seeping

My 2003 Subaru Outback was diagnosed with a seeping head gasket at 105k miles. There has been no overheating or engine failure, and I haven’t driven the car since finding out so I hope there is no permanent engine damage. My question is, is this car worth repairing? I know head gasket repairs can run into the thousands, and I don’t know if its worth the investment on a 20 year old car even though the miles are pretty low. Does anyone have any experience with how long their subaru lasted after repairing this issue and if it seemed to be worth it? Also what would be a reasonable mechanics offer to repair this? Any help is greatly appreciated!

My 2009 had a similar problem at about 110K. My mechanic didn’t think it was anything to worry about since the seep was very slow and nothing was in imminent danger of failing. I went ahead and had the head gaskets replaced anyway since I didn’t want to worry about it and wanted to keep the car. The cost was about $2,000. If your car hasn’t overheated from a catastrophic event then it isn’t very likely that any damage has been done. It’s important to use the stop leak formula that Subaru dealers carry to minimize the chances of something major developing. As to whether it’s worth it to replace the head gaskets, much depends on the overall shape of the rest of the car. I think the general opinion is that the new head gaskets are much more reliable than the factory ones, so the problem is not likely to recur. If you think the car is worth keeping, then the cost is a lot less than a car payment. Perhaps your mechanic can give the car a once over and let you know if it has other problems that make keeping it too much of a gamble or whether it’s a good bet to hang on to it.

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There’s no reason this car shouldn’t make it to 200K and 15 more years.

I’d probably spend the $2,000 and fix it if everything else on it is good and the car has been well maintained.

Has the car been garaged or is the paint beat to death and the dash cracking? Do they salt the roads where you live and the body and frame are rusting? Are you adding oil between oil changes? Barring other problems, JDMERE is right, it’s worth the 2 grand. And a good independent Subaru shop will know what else to check while they’re in there.

If you have a stick shift that’s a bonus, if you’ve been easy on the clutch then you won’t have any transmission problems for quite a while.

I’m curious, is the head gasket seeping oil onto the block or is it seeping coolant into the oil?

Subaru head gaskets tend to leak oil externally. You can live with that problem for quite some time. Often times people have the repair done because the oil burning off the exhaust becomes too unpleasant. Less common is the head gasket failing internally into the cooling system. But that usually happens after an overheat condition, like after a leaky radiator, etc. I’ve never seen a repeat failure after they are replaced once.

Cost is going to vary widely depending on where you live. $2000-3000. The engine comes out to replace the head gaskets. Items like clutch, radiator, hoses, rear main seal, oil pan gasket, etc. can add up.

The car has been garaged for most of its life and has had regular oil changes. It is an automatic transmission. Also, I do not know which type of head gasket leak it is. All I know is that it began leaking up by the radiator hose and had the check engine light on with the code PO420. Immediately it was taken to the shop for diagnosis and they said one of the head gaskets was leaking along with a very slow power steering rack leak.

Valve cover gaskets can leak, too. A good honest mechanic should be able to tell the difference between that and a head gasket leak. A leak by a radiator hose sounds like an external leak of coolant that might or might not be related to a head gasket leak. Head gaskets can leak internally or externally. They can leak oil or coolant.

The most serious is a coolant leak internally, the coolant going into the cylinder and out the exhaust pipe, and overheating ruining the engine.

The P0420 code is usually related to the efficiency of the catalytic converter. Sometimes it just indicates a bad O2 sensor, sometimes it means the cat needs replacing. It isn’t tied to leaks.

Hold your horses . . .

Part of properly diagnosing a P0420 code means making sure there are no (exhaust) leaks which could affect the functioning of the oxygen sensor(s)

Duly noted. Would a slow seep as described be enough to cause that?

Has anyone had any success just re torquing the head gasket?

I have not even tried it, valve cover gasket yes.

That worked for me on my 1984 Chevy Cavalier 2.0L engine. It had a small external leak - oil, I think - retorquing the head bolts took care of it.

All the other answers so far are on the mark, and especially be sure to verify it’s truly a head gasket leak leaking before you dive into this. However, engines are damaged very quickly by coolant contaminated oil, possibly even when not operating (it’s claimed that the coolant corrodes the bearing material, maybe someone can verify this, the few I’ve known were fixed asap). You can find much more on this topic on the forum subaruoutback.org , where the consensus is that if the car otherwise is a keeper, the repair is worth it and most likely good for the life of the engine. On that forum you’ll find specific recommendations for the quality of resurfacing, specific brands of head gaskets to use and avoid, and other things that should be performed while the engine is out of the car and open. The devil is in the details, so determine ahead of time precisely what will be done (and be sure they replace both sides!) Prices vary depending on the thoroughness of the job and local labor rates, beware those that seem too low.