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Old 04-27-2020, 02:11 AM   #2001
TexasWRXs
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Default 2018 WRX broken valve spring at 30,000 miles

WRX LTD 2018
29k miles
Cobb AP running MAP E30 stage 1 since about 4k miles, with a few tanks on MAP stage 1 93oct sprinkled in over the course of a year and a half
No other mods
E30 or 93oct from Chevron or Valero
Subaru oil, done by dealer
Ten minutes after leaving the house for work, going about 40 and slowing for a turn and it just shut off, dash lit up like a Christmas tree. Tried once to restart and it didn't sound right at all. Got it towed to the dealer.
I've never tracked it and I don't drag race, try to treat it nice with a decent warm up and cool down. I do engage in a fair amount of "spirited back road driving". I was ****ting bricks, fearing the worst.
Actual engine failure: an exhaust valve spring broke. Took a while, due to COVID-19, but the dealer was great all the way through. Warranty covered the engine work, and since they had it out I had them install a new clutch and flywheel, which they did at zero labor charge.
I've put about 350 miles on it since then, babying it, no WOT or redlining, breaking in the clutch....so far so good. Will take it back after a little more mileage for a follow-up.
This is my first Subaru and first turbo (well, not counting a Cummins diesel), so if anybody's had a similar experience or has any advice for me I'd love to hear it.
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Old 04-27-2020, 11:21 PM   #2002
Jersey Man10
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New clutch at 29k miles? Also I hope you're not using 5w30 dealer oil.
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Old 04-28-2020, 12:57 AM   #2003
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Originally Posted by Jersey Man10 View Post
New clutch at 29k miles? Also I hope you're not using 5w30 dealer oil.
I use Subaru 5w30. Change at 5000 miles. Beat it daily. Engine runs smooth. Stock tune tho.
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Old 04-28-2020, 12:07 PM   #2004
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Actual engine failure: an exhaust valve spring broke.
First I hear of that on a stock set up or even in general. Glad it was taken care of.
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Old 05-03-2020, 09:42 PM   #2005
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New clutch at 29k miles? Also I hope you're not using 5w30 dealer oil.
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Originally Posted by Jersey Man10 View Post
New clutch at 29k miles? Also I hope you're not using 5w30 dealer oil.
Yes. It didn't "need" the clutch replacement, but I took the opportunity to put a high performance clutch and lightweight flywheel in it to support future mods while I could do it for $0 labor.

And yes, I am using dealer supplied oil, changed by them at no charge every 4800 miles on average. I'll probably make a change now that the free service is running out, but everything I've read that was based on actual technical data suggests the dealer oil is just fine if you're not pushing it on intervals.

What oil do you use, and why?
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Old 05-03-2020, 09:45 PM   #2006
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First I hear of that on a stock set up or even in general. Glad it was taken care of.
Thanks, yeah I was pretty relieved.

Service writer said it's not very common, but they had just had another one like it recently...not on a WRX tho, IIRC.
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Old 05-04-2020, 11:40 AM   #2007
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...but everything I've read that was based on actual technical data suggests the dealer oil is just fine if you're not pushing it on intervals.
That goes out the window when you modify your engine. With just a little fuel dilution, the dealer oil and most Resource Conserving GF5 oils have the operating viscosity of a 20 grade whether you change it every 2,000 miles or 5,000 miles.
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Old 05-04-2020, 11:44 AM   #2008
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Thanks, yeah I was pretty relieved.

Service writer said it's not very common, but they had just had another one like it recently...not on a WRX tho, IIRC.
I know the BRZ/FRS had this issue.
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Old 05-04-2020, 11:47 AM   #2009
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That goes out the window when you modify your engine. With just a little fuel dilution, the dealer oil and most Resource Conserving GF5 oils have the operating viscosity of a 20 grade whether you change it every 2,000 miles or 5,000 miles.
Weight of oil is not as critical these days as in the old days.
These days, you want flow to remove heat from the bearings.
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Old 05-04-2020, 12:09 PM   #2010
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Weight of oil is not as critical these days as in the old days.
These days, you want flow to remove heat from the bearings.
So why does Subaru Japan recommend 5W-40 in a hard driven WRX? Weight is absolutely critical because the lower the viscosity the higher the risk of oil operating in the boundary lubrication regime.
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Old 05-04-2020, 01:26 PM   #2011
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So why does Subaru Japan recommend 5W-40 in a hard driven WRX? Weight is absolutely critical because the lower the viscosity the higher the risk of oil operating in the boundary lubrication regime.

This is a complex question that involves many different factors. Japan and the US have different emissions standards. This may have been the call for switching oil weights for the USDM engines. Secondly, the JDM FA20DIT may not be the exact same engine as the USDM FA20DIT which means they may not require the same oil due to those differences what ever they might be. For example the Manual WRX is not available in Japan, they only make WRX's in CVT's. While that may just be a transmission difference that also comes with any computer programming differences that makes the car operate differently warranting a change in other related systems including oil. Third this could be a very specific design differentiation based on rheological studies between JDM and USDM engines. You'd think it'd be as simple as higher oil weight means better lubricity at higher engine temperatures but in reality we know that its far more complicated than that. I'm not a rheologist but petroleum polymer chemistry goes far beyond simple oil weights or solids amounts.

One example of how this could differ is that I remember specifically people suggesting running 5w40 in a USDM FA20DIT WRX based on what you said that Subaru Japan runs 5w40 oil. You may even find many examples of people with engine failures running the heavier 5w40 oil in this very thread. Remember that this could have been the cause of a large number of engine failures due to spinning rod bearings. Why are the bearings spinning? Because an oil too thick couldn't adequately lubricate the bearings causing a metal to metal contact which results in the bearings to grip the crank and spin. While this was mostly an issue on 2015 and early 2016 WRX's this very well could have been exacerbated by people running the incorrect oil on their USDM WRX's
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Old 05-04-2020, 01:57 PM   #2012
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This is a complex question that involves many different factors. Japan and the US have different emissions standards. This may have been the call for switching oil weights for the USDM engines. Secondly, the JDM FA20DIT may not be the exact same engine as the USDM FA20DIT which means they may not require the same oil due to those differences what ever they might be. For example the Manual WRX is not available in Japan, they only make WRX's in CVT's. While that may just be a transmission difference that also comes with any computer programming differences that makes the car operate differently warranting a change in other related systems including oil. Third this could be a very specific design differentiation based on rheological studies between JDM and USDM engines. You'd think it'd be as simple as higher oil weight means better lubricity at higher engine temperatures but in reality we know that its far more complicated than that. I'm not a rheologist but petroleum polymer chemistry goes far beyond simple oil weights or solids amounts.

One example of how this could differ is that I remember specifically people suggesting running 5w40 in a USDM FA20DIT WRX based on what you said that Subaru Japan runs 5w40 oil. You may even find many examples of people with engine failures running the heavier 5w40 oil in this very thread. Remember that this could have been the cause of a large number of engine failures due to spinning rod bearings. Why are the bearings spinning? Because an oil too thick couldn't adequately lubricate the bearings causing a metal to metal contact which results in the bearings to grip the crank and spin. While this was mostly an issue on 2015 and early 2016 WRX's this very well could have been exacerbated by people running the incorrect oil on their USDM WRX's
Nice response. You're right, thicker oil does not guarantee that you will not have any issues. But note that even the US manual states that thinner oil is for for better fuel economy and thicker viscosity oil is "required" in hot temps, which of course, refers to an unmodified car.

Also note that my response to TexasWRXs was regarding the statement that "actual technical data suggests the dealer oil is just fine". I have my doubts that there is technical data suggesting the dealer oil is just fine when you run a Cobb AP running MAP E30 stage 1. If there is, I'm eager to see it.
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Old 05-04-2020, 02:13 PM   #2013
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Nice response. You're right, thicker oil does not guarantee that you will not have any issues. But note that even the US manual states that thinner oil is for for better fuel economy and thicker viscosity oil is "required" in hot temps, which of course, refers to an unmodified car.

Also note that my response to TexasWRXs was regarding the statement that "actual technical data suggests the dealer oil is just fine". I have my doubts that there is technical data suggesting the dealer oil is just fine when you run a Cobb AP running MAP E30 stage 1. If there is, I'm eager to see it.

I think this has to do with tuner philosophy in general. When I had my WRX tuned by Bren Tuning they recommended keeping with the 5w30 oil weight and suggested using Motul 8100 EFE 5w30 due to its low volatility and good wear resistance additives. I had my TGV/EGR deleted, a Grimmspeed EBCS installed and later the Cobb Flex Fuel kit and they still suggested I use 5w30 even in autocross events. They did however suggest I decrease the intervals for maintenance and servicing which means oil changes every 3k, spark plugs sooner, transmission fluids sooner, etc.


While there may not be specific data for some specific software and fuel usage, I doubt that Cobb or MAPerformance would actually take the time to acquire four WRX's and run them with 5w30, 5w40, 5w30 running their Stage 1 E30 MAP, and 5w40 with the e30 tune and compare the wear, oil composition before and after, etc. A large Design of Experiments like that is extremely expensive to run and I especially doubt they would recover their money finding out that information and it may never actually affect their bottom line which is selling OTS tunes they aren't even liable for when you use them. There are Technical Data Sheets you can acquire from various oil manufacturers and they often do tell you relative rheological data about the oil at certain temperatures. However all that data aside won't really tell you how the oil will perform in your engine with your given modifications.
Only the car manufacturer, Subaru, has actually run studies like this to find out what the best oil is for the reliability of the car. Obviously Subaru isn't going to recommend an oil weight that causes metal shearing because its too thin or causes rod bearing failure because its too thick *cough* Old BMW M3's running 10w60 that would eat rod bearings for lunch at 40k miles.

If you were really curious about how oil affects your engine you could take two oils you wanna look at get Blackstone labs to look at the composition before and after, look for metals or abnormal breakdown and stuff. Then you could take before and after oils to some other outside rheological lab and they could look at all the physical properties and junk and if you do your homework, read up on rheology and ask their opinion you could actually determine what the preferred would be for your car. I think blackstone testing kits are like 30 dollars a piece and getting some other analytical lab to look at rheology would be a couple hundred bucks a sample. If you think its worth it and you want whats best for your car then sure go for it but these are consumer cars, disposable in nature and more or less aren't designed to last any longer than the life cycle of any other car.

Last edited by Mike1Juliet; 05-04-2020 at 02:21 PM.
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Old 05-04-2020, 02:24 PM   #2014
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If i followed Subarus advice on everything then i wouldnt be driving an fbo flex fuel car.

Been running 0w40 Mobil 1 FS European formula since first oil change and before stg 2 tune at 1500mi and today have 23k, 20k of which was done on e85 with no 91oct intervals. Car still goes vroom.

l am sure that Subarus advice, just like their oem tune, caters to the average folk out there. Theres nothing average about me or the state of my car.

Quote:
Only the car manufacturer, Subaru, has actually run studies like this to find out what the best oil is for the reliability of the car. Obviously Subaru isn't going to recommend an oil weight that causes metal shearing because its too thin or causes rod bearing failure because its too thick
Exactly. Did they do this testing on oem cars or on highly tuned fbo cars my friend? Did they do this testing with normal daily driving conditions in mind or extremes that some of us put these cars through?

I think you need to reassess your position a bit.
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Old 05-04-2020, 02:52 PM   #2015
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Originally Posted by Mike1Juliet View Post
I think this has to do with tuner philosophy in general. When I had my WRX tuned by Bren Tuning they recommended keeping with the 5w30 oil weight and suggested using Motul 8100 EFE 5w30 due to its low volatility and good wear resistance additives. I had my TGV/EGR deleted, a Grimmspeed EBCS installed and later the Cobb Flex Fuel kit and they still suggested I use 5w30 even in autocross events. They did however suggest I decrease the intervals for maintenance and servicing which means oil changes every 3k, spark plugs sooner, transmission fluids sooner, etc.


While there may not be specific data for some specific software and fuel usage, I doubt that Cobb or MAPerformance would actually take the time to acquire four WRX's and run them with 5w30, 5w40, 5w30 running their Stage 1 E30 MAP, and 5w40 with the e30 tune and compare the wear, oil composition before and after, etc. A large Design of Experiments like that is extremely expensive to run and I especially doubt they would recover their money finding out that information and it may never actually affect their bottom line which is selling OTS tunes they aren't even liable for when you use them. There are Technical Data Sheets you can acquire from various oil manufacturers and they often do tell you relative rheological data about the oil at certain temperatures. However all that data aside won't really tell you how the oil will perform in your engine with your given modifications.
Only the car manufacturer, Subaru, has actually run studies like this to find out what the best oil is for the reliability of the car. Obviously Subaru isn't going to recommend an oil weight that causes metal shearing because its too thin or causes rod bearing failure because its too thick *cough* Old BMW M3's running 10w60 that would eat rod bearings for lunch at 40k miles.

If you were really curious about how oil affects your engine you could take two oils you wanna look at get Blackstone labs to look at the composition before and after, look for metals or abnormal breakdown and stuff. Then you could take before and after oils to some other outside rheological lab and they could look at all the physical properties and junk and if you do your homework, read up on rheology and ask their opinion you could actually determine what the preferred would be for your car. I think blackstone testing kits are like 30 dollars a piece and getting some other analytical lab to look at rheology would be a couple hundred bucks a sample. If you think its worth it and you want whats best for your car then sure go for it but these are consumer cars, disposable in nature and more or less aren't designed to last any longer than the life cycle of any other car.
Note that Motul EFE 5W-30 meets ACEA C3 and has a High Temp High Shear of 3.5 cSt's so it is not a GF5 Resource Conserving oil like the Subaru oil. Your oil analysis advice is good, although I would recommend Oil Analyzer's Inc over Blackstone as they have the ability to do an actual fuel dilution test via Gas Chomatography whereas Blackstone only extrapolates the fuel dilution based on the flashpoint result.

Lots of FA20DIT uoa's here:
https://forums.nasioc.com/forums/sho....php?t=2657990

Unfortunately, even with all of those uoa's, there are only a handful or less of uoa trends. And a uoa is only good for telling you the condition of the lubricant but it is not a measure of determining that you will never have a failure.
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Old 05-04-2020, 10:57 PM   #2016
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17 wrx 6mt
Spun rod bearing cylinder #2
74k
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Old 05-05-2020, 01:30 AM   #2017
CIdude5252
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Default First engine

2016 WRX base
75k (bought used with 52k)
Cobb AP, 93octane stage 2
Cobb j pipe, ets intake, removed restrictor pill, thick lady riding shotgun
5w30 Pennzoil
#1 cylinder spun rod bearing, (sounded like a machine gun knocking)
...I purchased a power train warranty from the dealer when I purchased the car. At first they denied the claim when the shop quoted replacement because of various "most likely modifications". After a month of explaining the intake (the only mod they could prove), they offered to reimburse for the cost of a used engine if I did it my self with before and after pics. I did it in my driveway, and they honored the reimbursement...
Engine # 2
Purchased a used motor (from a wrecked WRX) from a salvage yard. Same everything except this one had 67k on it. 300miles after installation, it started knocking. Exact reason unknown because the salvage yard did a small investigation of sorts, and offered a full refund including shipping....it went straight on the pallet.....I'm buying a damn
camry
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Old 05-05-2020, 02:10 AM   #2018
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Originally Posted by CIdude5252 View Post
2016 WRX base
75k (bought used with 52k)
Cobb AP, 93octane stage 2
Cobb j pipe, ets intake, removed restrictor pill, thick lady riding shotgun
5w30 Pennzoil
#1 cylinder spun rod bearing, (sounded like a machine gun knocking)
...I purchased a power train warranty from the dealer when I purchased the car. At first they denied the claim when the shop quoted replacement because of various "most likely modifications". After a month of explaining the intake (the only mod they could prove), they offered to reimburse for the cost of a used engine if I did it my self with before and after pics. I did it in my driveway, and they honored the reimbursement...
Engine # 2
Purchased a used motor (from a wrecked WRX) from a salvage yard. Same everything except this one had 67k on it. 300miles after installation, it started knocking. Exact reason unknown because the salvage yard did a small investigation of sorts, and offered a full refund including shipping....it went straight on the pallet.....I'm buying a damn
camry
Lmao.. why buy a used POS motor you know was ragged on???? You didn't even have the decency to rebuild it with better parts while you had it out?.. OMG.. please enjoy your Camry, its a great family sedan, more comfortable and a larger trunk! Good luck.
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Old 05-06-2020, 01:24 AM   #2019
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Thank you, Mr. Engine Jesus.

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Old 05-06-2020, 09:12 AM   #2020
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Thank you, Mr. Engine Jesus.
Did you just post on facebook a few days ago?
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Old 05-09-2020, 12:08 AM   #2021
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Did you just post on facebook a few days ago?
No. It's been over a year.
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Old 05-09-2020, 02:40 AM   #2022
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Also note that my response to TexasWRXs was regarding the statement that "actual technical data suggests the dealer oil is just fine". I have my doubts that there is technical data suggesting the dealer oil is just fine when you run a Cobb AP running MAP E30 stage 1. If there is, I'm eager to see it.
Fair point. I appreciate this discussion guys.
So what's the reasoning behind a moderate power bump from e30 on an otherwise stock car necessitating a different oil?
Is the ethanol worse from a fuel/oil dilution standpoint? Is it just increased stress on the oil that comes with making the extra hp? ..trying to get educated.

Last edited by TexasWRXs; 05-09-2020 at 12:46 PM.
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Old 05-09-2020, 09:36 AM   #2023
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Fair point. I appreciate this discussion guys.
So what's the reasoning behind a moderate power bump from e30 on an otherwise stock car necessitating a different oil?
Is the ethanol worse from a fuel dilution standpoint? Is it just increased stress on the oil that comes with making the extra hp?
I wouldn't call a 80 whp plus gain over stock a moderate power bump. I use Motul 5w-30 as it was recommended by my tuner and by my shop @ 3,000 mile intervals (tons of short trips, idle, harsh weather condition driving). 30,000 mile spark plug change intervals too.
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Old 05-09-2020, 09:58 AM   #2024
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^What Straight6 said.

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Originally Posted by TexasWRXs View Post
Is the ethanol worse from a fuel dilution standpoint? Is it just increased stress on the oil that comes with making the extra hp?
Both. Not sure if ethanol is any worse, but even in stock form, the uoa's show that anywhere from 2-5% of your oil is fuel. And if your tune is a little rich you will have even more fuel and lower viscosity. GF5 oils can have an operational viscosity of a 20 grade even on a stock car.

Quote:
Why is fuel dilution a problem?

- Reduced oil viscosity interferes with formation of a durable lubricating film, inviting wear. It also negatively affects the oil's ability to function as a hydraulic fluid, which is critical in engines with variable valve timing

- Fuel can wash oil from the cylinder wall, causing higher rates of ring, piston and cylinder wear

- Reduced effectiveness of detergency additives limits the oil's ability to guard against deposits

- Increased oil volatility results in higher oil consumption, requiring more frequent top-offs

- Accelerated oxidation reduces the oil's service life and requires more frequent oil changes
https://blog.amsoil.com/what-is-fuel...why-is-it-bad/

Last edited by bluesubie; 05-09-2020 at 12:01 PM.
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Old 05-09-2020, 01:51 PM   #2025
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Good stuff guys, thanks!
I'm at about 1,000 miles since the engine rebuild....was planning on scheduling a follow-up visit with the dealer just to recheck things pretty soon, and was debating having them do an early oil change...but I'm rethinking that and will just do it myself, probably with Motul or one of the other heavy duty low saps 5w30 oils, and get a UOA done to better understand what's going on, maybe at 5k? Does that sound like a smart plan to you guys? Most of my driving is a 30-40 minute commute twice a day mostly at highway speeds, with some back roads blasting on the weekends. It's Texas, so it's going to be getting hot here soon, and for now I'm off of the ethanol and just running MAP's stage 1 93 octane tune.
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