I for one can confirm that my 2012 FB20 needs the coolant conditioner. My dealer put in the BG Coolant Conditioner and it started drinking coolant. I poured the Subaru branded Coolant Conditioner directly into the radiator and it stopped the consumption. That was 30K miles ago. No issues to note.
2015 Subaru 2.0 Head Gasket Failure at 136K Miles
- Thread starter dogememe
- Start date
I for one can confirm that my 2012 FB20 needs the coolant conditioner. My dealer put in the BG Coolant Conditioner and it started drinking coolant. I poured the Subaru branded Coolant Conditioner directly into the radiator and it stopped the consumption. That was 30K miles ago. No issues to note.
I am surprised it lasted that long
You probably have a leak somewhere. Check the crossover pipe o-rings.
Cadillac did it for years and years. The engines were bad for other reasons, but if you put the conditioner in there it worked fine
To throw some more mud in the water, my wife's 15 Forester has been an absolute freight train. It has just shy of 170,000 mi on it and realistically tires, brakes, oil, a clutch, rear wheel bearings and two CV shafts.
Currently it needs control arm Bushings, It's getting STI aluminum control arms with spherical joints.
I don't know. Maybe the manual car is getting rung out. Help the situation? I have heard of several CVT Subarus being misdiagnosed with oil in the coolant, because the CVT cooler failed and leaked into the coolant.
Compared to the Honda 4-cylinder head gasket issue Subaru's been pretty quiet in the scheme of things. I feel like there was a glut of people who drove their late 90s to early 2000s Japanese vehicles, from the heyday of reliability, until the mid-2010s. Modern stuff isn't as reliable, And that's across the board. So we get a lot of people upset.
as a mechanic, 140,000 mi seems short, but not outside the realm of normal used car maintenance. Like has already been stated, I'd have suggested that they throw a used engine at it, at an indie shop, And drive it for a couple of months. If they still feel reluctant about it then sell it.
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My understanding of that 'conditioner' is that it was for the EJ25's that leaked coolant externally, not so much for ones with other types of leaks (there was the gen that leaked coolant to combustion, and the last of the EJ253s that leaked oil externally)
Precisely. It works great for seeping head gaskets, but that’s about it. My parents’ VQ35 has HG’s that are seeping externally and requires 4-8 ounces of top off every year. 1 bottle of the Subaru goop and the level has been rock solid.
I too thought it was for EJs and not FBs.
When I did head gaskets on an '11 with EJ I could swear Six Star specifically said not to use anything with their HGs (which I think Trav says are Cometic)
I think the OPs coolant in oil could be from the plastic pcv union part under the AC compressor.
The FB engine channels the coolant to the heads separate of the HG. 85 percent coolant available to heada, 15 percent available to block when coming from radiator. Drive one watching the coolant temp sensor data compared to EJ it is very stable.
I've done 1 FB head gasket on a 173,000 mile 2014 FB25 that doesnt consume any measurable quantity of oil in an oil change. It was exhaust gas to coolant failure of gasket cylinder 1.
I would not hesitate to do this to another FB engine if it needed it.
The FB engine channels the coolant to the heads separate of the HG. 85 percent coolant available to heada, 15 percent available to block when coming from radiator. Drive one watching the coolant temp sensor data compared to EJ it is very stable.
I've done 1 FB head gasket on a 173,000 mile 2014 FB25 that doesnt consume any measurable quantity of oil in an oil change. It was exhaust gas to coolant failure of gasket cylinder 1.
I would not hesitate to do this to another FB engine if it needed it.
Honda did the exact same thing on their 1.5L engines:
Here's Why the Honda L15 Turbo Engine is a FAILURE by speedkar99 on YouTube.
And the Ford Ecobooms ...
