3.0R Head Gaskets

Recently, I've noticed my 2008 3.0R has been using some coolant. Maybe a cup or two every 3-4 months. I drive about 2-3K miles per month The engine has 121K on it and the car is perfect otherwise. I know the 3.0 engine is arguably bullet proof, and the coolant loss is by no means significant and is probably a minor leak I haven't found yet, but it got me thinking.

I've read the NA engines have problems with head gaskets due to the material they used, namely the 2.5l series engines. Did the 3.0 engine have similar problems?

I've heard they corrected that issue in the early/mid 2000s with a gasket material change. Any truth to that?

If for any reason the head gaskets were bad and needed to be replaced, who makes good aftermarket head gaskets for the 3.0 series engines?

Thank you for any insight on my over reaction!

How does your metal coolant pipe look that connects to the oil cooler and runs to the back of the motor? If it's really rusty like mine was, it might have a leak.

Do you have any coolant "crusties" at the bottom of the engine at the headgaskets? Small crusty bits are normal. But a lot of gunk would indicate an external HG leak.

Sometimes either of my 3.0Rs will lose a few cups of coolant over the course of months, and then they stop and seem to level out for a few months. I haven't really figured it out.

Lastly, there is a market for JDM ez30 motors on Ebay. I think most people in the US buy these ($1500 shipped) rather than doing a headgasket job. The JDM engines work for us with a few minor mods. The ez30 is a pain for headgaskets. The timing cover alone has like 75 Allen head screws that love to strip.

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Check out my thread if you have the same problem:

http://legacygt.com/forums/showthread.php/coolant-pipe-14165aa021-244357.html?t=244357

Would you have the part number for the pipe on the other side that goes to the oil cooler?

I replaced both, and bought the parts on Ebay:

21328AA121 $110 Oil Cooler Pipe

14165AA021 $45 Water pipe return

I replaced the entirety of both pipes (i.e. didn't follow flystyles method). It's kind of a pain to fully replace it. You have to remove the manifold intake box, a few hose clamps behind the engine, 1 motor mount nut, lift the engine as far as it will go, and snake a super awkward shaped metal pipe in a tight spot. It took a couple hours for me to do it, but I'm glad I did. I had a giant rust/coolant wart growing on one pipe, and it turned into a large hole by the time the pipe was off the car.

If you do replace either of these pipes, you may want to use the Subaru coolant conditioner when you refill the coolant as it can patch up minor headgasket or radiator leaks.

For the reasons Dispatch said, I just did the small section. Its coming up on two years and it still looks great .

I got my parts from quirkparts.com. Regardless if you replace a portion or the whole thing, take the extra step to spray the pipe with some protective coating. Otherwise it will just happen again.

Regarding the conditioner. I purchased some but there were so many chunks floating around in the bottle I didn't use it. I change my coolant enough where I rather not run with it. Your call on that one.

For the reasons Dispatch said, I just did the small section. Its coming up on two years and it still looks great .

I got my parts from quirkparts.com. Regardless if you replace a portion or the whole thing, take the extra step to spray the pipe with some protective coating. Otherwise it will just happen again.

Regarding the conditioner. I purchased some but there were so many chunks floating around in the bottle I didn't use it. I change my coolant enough where I rather not run with it. Your call on that one.

Finally got around to taking a look under the car. The pipes are rusty, but not leaking (yet). I'll get them replaced sooner than later. The car is due for a cooling system service and probably a new thermostat, upper/lower hoses, and radiator cap. I've already got the coolant conditioner (two bottles) and all parts will be OEM. I'm thinking of coating the new metal pipes with a rubberized undercoating.

Also - Head gaskets look good with no external leaks apparent. coolant level has not dropped in over a month either.

Does anyone have a recommendation on replacement coolant?

Finally got around to taking a look under the car. The pipes are rusty, but not leaking (yet). I'll get them replaced sooner than later. The car is due for a cooling system service and probably a new thermostat, upper/lower hoses, and radiator cap. I've already got the coolant conditioner (two bottles) and all parts will be OEM. I'm thinking of coating the new metal pipes with a rubberized undercoating.

 

Also - Head gaskets look good with no external leaks apparent. coolant level has not dropped in over a month either.

 

Does anyone have a recommendation on replacement coolant?

That's good to hear I would replace all the parts, skip that conditioner and go with PEAK 50/50 Long Life (pre-diluted). Also go with a OEM Subaru Thermostat and Radiator cap.