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Old 08-31-2012, 04:11 PM   #1
BrandonDrums
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Default Rod Bearing Failure Nightmares/Stories (One thread to rule them all)

READ BEFORE YOU POST!

I first created this thread after experiencing a couple back to back rod-bearing failures due to some bad shop advice and work so I wanted to learn more about the problem to prevent future issues. The thread ended up taking off and has largely become the primary thread about this well-known and unfortunately 'notorious' Subaru issue.

This thread has been going for several years and through many expert contributors commenting and sharing we have lots of great information to help Turbo Subaru owners understand this issue. The thread is extremely long so in an effort to prevent some of the same questions being asked over and over I've made a synopsis for new visitors to read and/or be pointed to to catch them up on the main themes detailed out in the thread.

I will come back and make changes to this initial post sharing sources and quick links to discussions as time allows to further bolster this initial post. Some of the explanations are just high-level conceptual overviews meant for quick reading and aren't 100% accurate as a result.

Hopefully this synopsis will help future visitors understand the range of topics discussed in the thread without having to read the whole thing.

I feel strongly that the biggest contributor to these failures is the increased popularity and increased sales in general but also the increased rates in which these cars are modified. The WRX and STI are likely the highest-volume "Tuner" car besides the Mustang and perhaps the most likely vehicle to have power modifications to the engine both in hardware and ECU flashes. They've become extremely prolific and as a forced-induction engine are very effective in pulling more power out of the stock engine setup.

Regardless of modifications and tuning, these cars are driven hard by an enthusiastic community who push these cars to redline quite frequently and there are some 'weak points' from the factory that have made for some failure issues to come up both stock and modified as a result:

OIL:
For CAFE reasons, Subaru began recommending Resource Conserving 5w-30 oil in their turbo models around 2008 or so even though they didn't change the engine itself or cooling system to help the 'weaker' oil deal with the harsh conditions these engines often see in being driven hard or being lightly modded.

The manual used to clearly state that harsh driving conditions warranted a temporary fill of heavier weight oil and a lower oil change interval for Turbo Models through approximately 2006-2007. Subaru eventually removed those recommendations roughly around 2008 or so which surely has contributed to the number of Turbo Subaru drivers sticking with the inferior factory oil fill and elongated oil change intervals even after tracking their car, installing aftermarket tunes or simply driving around full throttle on a regular basis as so many trubo subaru drivers do.

There have been many reported cases where Subaru owners have been hassled, pushed and otherwise threatened to have their warranties voided if they didn't use the oil specified in the manual. Even in some cases the dealerships required the owner to have all of their oil changes performed at the dealership or have detailed receipts of the type of oil and the date and mileage of the oil change kept to honor any warranty claim. Unfortunately this is not legal and also bad advice as the dealerships do not understand that the oil being recommended is to achieve the best possible EPA numbers and doesn't provide the maximum protection for the engine under harsh driving conditions.

Tune:

1: Fuel
Over the years for the same CAFE/EPA pressures, Subaru has slowly changed the factory tune logic to also meet increasing fuel economy and emissions standards that leaves a little less safety margin for reducing knock when under harsh driving or using lower quality/octane fuel that is often attributed to some of the apparent increased failure rates since 2006. Increased Ring Land Failures also increased in this time period for the same reasons. These changes began in the later years of the GC chassis (reaching a peak in 07 through 09) but have been found to continue through even the current generation STI.

The main issue with the tune is the changeover from Closed-Loop to Open-Loop fueling has continually been delayed later in the RPM band and further into the throttle input range. In "Closed Loop" the ECU targets a specific air-fuel ratio - in this case STOIC which is the cleanest and most efficient fuel ratio but also the most lively and prone to knock.

**Closed Loop uses the O2 sensor to constantly check the exhaust stream to measure the effective Air-Fuel ratio and then applies learned and pre-determined corrections to the injectors to keep the fuel mixture on target.

**Open Loop is where the engine ignores sensor feedback and instead applies a set amount of fuel based on calculated intake volume, load, rpm, throttle %, boost levels etc. It's up to the accuracy of the tune to ensure that the targeted fuel ratios are met because the ECU does not apply automated changes to the fuel system to compensate for errors during Open Loop. From the factory, Open Loop fueling tables are typically quite safe for the engine but are being utilized less and less as more driving conditions are being addressed by a Closed Loop fueling strategy. Closed Loop is great for more advanced Direct Injection engines where the fuel can be controlled much more accurately without delay but for Port Injected engines can be a bit of an inexact science regardless of sensor accuracy or processing power.

2: Knock Correction:
Furthermore, some changes have been documented to the knock correction logic where the engines are allowing larger knock events before retarding timing or changing fueling conditions again in an effort to maximize fuel efficiency at the expense of more potential engine wear. The EJ series engine had not changed mechanically very much to deal with the higher potential stresses since 2004 in general and in some cases, issues with build quality and component quality have been found as production numbers increased.


Build Quality:
Overall:
There have both been production runs where faulty engine bearings and engine rings have been suspected to be used as well as runs where Subaru admittedly found defects and issued service bulletins (need to find more info to cite on this). Many engine builders have also found production runs where the tolerance range for Rod Bearing Clearances seemed to widen from the well-known .0014''-.0018'' to .0012''-.0018'' (citation also needed, Maxwell Power in this thread detailed out this scenario) which is independent of material defect but contributes to oiling issues under high-stress that can lead to failure.

While the mechanical issues appear to have been largely addressed starting towards the end of the GR model run (2012-2014 on) there are still many cars affected that are experiencing failures from what it seems.

Oil Pickup:
There have also been many recorded instanced where the Oil Pickup Tube has failed causing oil starvation to the engine. Popular aftermarket mods for rebuilt/built engines is a better pickup tube like a Killer-B which is a popular affordable brand.

Oil Pump:
Earlier EJ257 engines used a smaller 10mm oil pump but Subaru began using a 11mm oil pump in 2008. The actual reason for this increase is unknown but most likely is due to the addition of dual-avcs engines where a little more load on the oil system would be present from 2 more oil pressure actuated cam gears. Many engine builders use the larger 11mm pump even on single AVCS engines with the idea that better oil pressure can be sustained at higher RPM's. Opinions are mixed on whether larger oil pumps improve or exacerbate the issue at all but Rod Bearing failures are mostly an oil-related issue. Fear that too large an oil pump can cause more failures is due to over-pressurizing the oil and causing cavitation - bubbles from pressure and heat in a fluid.

Crankshaft:
Crankshaft Coatings: Subaru has gone through several renditions of crankshaft surface treatments that have limited data on how they truly impact bearing failure rates. Nitride Coated Crankshafts were used initially to replace the traditionally Polished Crankshafts and then later replaced by a Heat Treated Crankshafts from the factory (details and citation forthcoming). These treatments/coatings are intended to harden the crankshaft surface to prevent marring and scoring from metal to metal contact with the bearing surfaces. The only conclusive recommendation is that proper oil and bearing clearances are far more important than crankshaft coatings although many engine builders find that fresh treated crankshafts are more desierable in their builds.

Precautions:
  1. Ignore the manual and use a non resource-conserving _W-40 oil
    There are 0w-40, 5w-40 and 10w-40 oils well documented in this thread that perform very well in turbo Subaru engines. The most commonly found and popular oils are: Shell Rotella T6 5w-40, Mobile 1 Advanced Full Synthetic 0w-40 (DO NOT USE REGULAR OR GREEN CAP MOBILE 1), Pennzoil Ultra 0W-40 just to name a few with good data. The first number matters less than the 2nd number but if in doubt about trying an oil go for a thicker W weight like 10w-40 if you can't find the named oils above.
  2. Taking extra precaution to use fresh high-octane fuel
  3. Increasing oil change intervals in general but especially when driven hard.
  4. Avoiding prolonged runs at or near redline and WOT. If you drive heavy, change your oil more frequently and use better oil!!
  5. Avoiding out of the box staged tunes when you're unable to verify the 'health' of the tune via datalogging & wherewithal to make corrective changes
  6. Not installing aftermarket intake components without a proper tune as the accuracy of the MAF sensor's readings can be affected causing improper fuel ratios
  7. drive it like you bought it. These cars are fun but they are essentially CHEAP fun so don't expect them to pull racetrack duty out of the box like a supercar.
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Last edited by BrandonDrums; 10-10-2016 at 06:17 PM.
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Old 08-31-2012, 04:33 PM   #2
punchjamesarnol
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... Sorry to hear about your motor... Bummer man! I had mine fail on my stock '10 from ringland failure to finally seizeing the motor... I had her all rebuilt with the good stuff, the oil pump and all lines replaced as well. I'm barely over 3,000 miles and she is well broken in. Keeping my fingers crossed on this one.
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Old 09-04-2012, 11:22 AM   #3
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Thanks for the reply! Anyone else care to post their rod bearing failure story and post-rebuild success/problems?

Perhaps I should have put this thread in the General discussion since it's not specific to just 2.5's....
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Old 09-04-2012, 12:18 PM   #4
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My brother just bought my 07 wrx from me, drove it about 250 miles missed a shift from 1-2 and then oil pressure dropped off, followed by this... take a listen

https://www.youtube.com/watch?v=Bh3U...eature=mh_lolz

Is this the sound of rod knock and eng failure?

(I just got back to nm and he lives in reno nv so there is no way for me to get up there and take a look at the car.)
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Old 09-04-2012, 12:42 PM   #5
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Quote:
Originally Posted by casaus19 View Post
My brother just bought my 07 wrx from me, drove it about 250 miles missed a shift from 1-2 and then oil pressure dropped off, followed by this... take a listen

https://www.youtube.com/watch?v=Bh3U...eature=mh_lolz

Is this the sound of rod knock and eng failure?

(I just got back to nm and he lives in reno nv so there is no way for me to get up there and take a look at the car.)
Yup, pretty much without a doubt a Rod Bearing Failure

I'm really sorry man, I highly recommend draining the oil to diagnose rather than running the engine any more. Just to prevent any flake from circulating around the engine any more than needed.

It's funny, a stall out was the last "abuse" event on my car before it spun a bearing. I let my uncle drive my car for a cruise. He's battling prostate cancer and he was telling me about his treatment so he wasn't paying attention. We pulled up to a stopsign after cruising in 5th and he stalled it out reaaaaallly bad. I was trying to tell him "Push in the clutch push in the clutch" but his mind was elsehwere, I had to pull the shifter hard to pull it out of gear but it was too late.

The engine made horrible noises while it stalled in top gear but it started right up and drove fine for a week. I don't know if it was that stall that caused the failure or if the engine builder who put in my last engine re-used the oil cooler from my last spun bearing or if I just abused the car to the point of failure on my own and I'll never know.

I just want to hear more from folks who've had a rod bearing failure and rebuilt to learn how long their rebuilds have lasted without problems after the fact because one of the builders I've talked to for fixing my current bearing issue said the chances of failure after spinning one rod bearing are extremely high unless you replace every single oil passage on the car, replace the entire longblock and even the turbo.
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Old 09-04-2012, 03:32 PM   #6
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OP,
Did you install a new crankshaft with the second engine? or was it resurfaced?
Also what was the cause of the failure on that second engine??

*To add a note here,
Im a subaru certified tech, for warranty purposes we cant replace many of these parts like, oil pan, oil pump, oil cooler or any of the related lines. We are instructed to flush them and inspect the oil pump for damage. The oil pump can be completely stripped down, cleaned and inspected. If its scored or scratched in the pump housing then yes, it is to be replaced. Ive yet to ever have a engine come back with spun rod bearings for not replacing any of those parts. You just have to have the right parts cleaner and time to make sure it is 99% clean.

I have had 2 engine Ive built come back, but it was many miles later and in both cases they were on the track during the failure.

For built engines, oil clearances and other things cant be put to OE Spec tolerances or clearances for that matter or you will have failures. It takes lots of time and knowledge to get these things correct. I often have to have bran spakin new crankshafts sent out for machining! Yes even the Nitirde cranks are not good enough for me. Many get .005 thousandths removed to get my clearance right where i want it. I dont do this for warranty jobs, but I do for customers that want built engines.

Keep this in mind too, I NEVER trust machined crankshafts for over size bearings in a Performance application. They dont last!!!! New Nirtide cranks are only $325..... Turned/machined cranks after a bearing failure are just worthless and youre asking for it to happen again very soon. Ive got a pile of cranks here going to the scrap yard. Many are saveable for turning but I just dont risk it anymore.

Last edited by UK-Wagon; 09-04-2012 at 03:46 PM.
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Old 09-04-2012, 04:27 PM   #7
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Quote:
Originally Posted by UK-Wagon View Post
OP,
Did you install a new crankshaft with the second engine? or was it resurfaced?
Also what was the cause of the failure on that second engine??

*To add a note here,
Im a subaru certified tech, for warranty purposes we cant replace many of these parts like, oil pan, oil pump, oil cooler or any of the related lines. We are instructed to flush them and inspect the oil pump for damage. The oil pump can be completely stripped down, cleaned and inspected. If its scored or scratched in the pump housing then yes, it is to be replaced. Ive yet to ever have a engine come back with spun rod bearings for not replacing any of those parts. You just have to have the right parts cleaner and time to make sure it is 99% clean.

I have had 2 engine Ive built come back, but it was many miles later and in both cases they were on the track during the failure.

For built engines, oil clearances and other things cant be put to OE Spec tolerances or clearances for that matter or you will have failures. It takes lots of time and knowledge to get these things correct. I often have to have bran spakin new crankshafts sent out for machining! Yes even the Nitirde cranks are not good enough for me. Many get .005 thousandths removed to get my clearance right where i want it. I dont do this for warranty jobs, but I do for customers that want built engines.

Keep this in mind too, I NEVER trust machined crankshafts for over size bearings in a Performance application. They dont last!!!! New Nirtide cranks are only $325..... Turned/machined cranks after a bearing failure are just worthless and youre asking for it to happen again very soon. Ive got a pile of cranks here going to the scrap yard. Many are saveable for turning but I just dont risk it anymore.
Humm, that's an interesting take. So you machine brand new crankshafts thusly removing the Nitride coating that makes them supposedly superior but if they've had a failure you toss them out? From what I know about machining, you get crap everywhere on the part itself by machining it just like you do during a failure so there should be zero difference in reliability between a re-machined crankshaft from a bearing failure and a brand new crankshaft that you've machined to meet a specific tolerance unless you aren't checking the re-used cranks for straightness etc.

I also seem to understand that those new OEM bearings used on the nitrite cranks are so much more dangerous than the old lead filled bearings during a failure and here in the states I don't know if Subaru has the same flush and re-use protocol for warranty repairs because of it. A shard small enough to get past the pickup screen and through every oil passage in the car is still hard enough to mar and damage a bearing now. Those old ones were much softer and didn't pose as much of a threat if they were small enough to get past the pickup tube every once in a while from what I understand.

To answer your question about my 2nd engine, I think the rods block and heads were original, the crank and the pistons were brand new. The block was bored due to scoring from the blown ringland by .002'' in each cylinder and .002'' cold-gap was used to fit weisco forged pistons and rings.

ACL bearings matched to OEM clearances for the rods and mains were used and the heads were checked for leaks, resurfaced and re-used.

Here's where it gets fuzzy, the oil cooler was used but I don't know if it came from the 2.5 w/ the ringland failure or from my 2.0 with the bearing failure. Judging by the picture, it's certainly used although I was never told explicitly if it was used or not.

You can tell, the oil cooler in this pic is used. By which engine, who knows.


The only thing I've been told by that shop was that "a couple of years ago we never replaced the oil coolers on rod bearing failed engines, we'd just clean them out like crazy but we kept getting those engines back with new failures over and over so now we just replace it" They did my build "a couple of years ago" in Nov of 2010.

That's not the point though, my engine was put through hell through it's relatively short life. The first tune on it was absolute crap and the street tune that replaced that first tune turned out to knock around 3200 rpm a whole lot when I bought a laptop and started to log and peek at learningview. For 4 months it had been knocking and learning view was a nice little hodgepodge of 5-10 degrees of learned timing retard, namely from .7-1.10 g/s of load at 2600-3400rpm. THAT'S when I decided to learn how to tune myself which lead to other abuses.

Last edited by BrandonDrums; 03-01-2016 at 06:27 PM.
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Old 09-06-2012, 03:43 PM   #8
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no more failure and rebuild stories?
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Old 11-18-2012, 10:10 PM   #9
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Default my short story

Hi, I'm new here and this is my first post/reply. I've been an ASE certified master tech for a few years now. I have rebuilt 3 1/2 air cooled porsche 911 engines and I'm in the process of rebuilding #2 &3 water cooled porsche engines. I bought an 02 wrx wagon (my favorite) off of craigslist for $2200. Yes, it was knocking, but besides some hail damage it was in really good condition. So, i pulled the engine and found the number 4 connecting rod bearing had spun. This car has 173k on the original engine, so i guess it was about due. It had wiped out the crankshaft, so i bought a brand new one from the local dealer along with one connecting rod. I have no plans on building lots of horsepower, so the stock will do. Had the connecting rods sized and will be balancing the pistons and then the assemblies. I have ported and polished the turbo, turbine and compressor side, will be pnp-ing the heads, intake, tumble flap housings, exhaust pipes, throttle body, and anything else that looks like it needs it. I want to do this once, and so any advice on fault proofing would be appreciated. I will post updates on progress and how its doing after.
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Old 11-19-2012, 03:38 PM   #10
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I myself have been blessed with a wonderful rod failure also. I orginally cracked a ringland on piston 4 when running the car with a Stage 2 setup. I then bought a used but new short block that spun a rod only 3k miles later. This time around I built a completely new long block with all forged internals. Currently have 2500 miles on the setup and 415whp
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Old 11-19-2012, 04:06 PM   #11
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Quote:
Originally Posted by mackeymx View Post
I myself have been blessed with a wonderful rod failure also. I orginally cracked a ringland on piston 4 when running the car with a Stage 2 setup. I then bought a used but new short block that spun a rod only 3k miles later. This time around I built a completely new long block with all forged internals. Currently have 2500 miles on the setup and 415whp
Oh jeez, that's tough stuff. What do you think caused the bearing failure so quick? Was it a cracked oil feed tube or debris in the oil system or perhaps just a improperly assembled block?

I'm trying to see what the average life of a repair is after a failure. Some say repeat failure is imminent if you don't change out every single oil related component. Not just the oil cooler but oil feed lines, oil pump, avcs oil passages and cam pulley actuators, oil pan and pickup tube.

I'd like to hear of someone getting over 100k miles after a rod-bearing failure repair that wasn't just a longblock swap.
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Old 11-20-2012, 10:47 PM   #12
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Quote:
Originally Posted by BrandonDrums View Post
Oh jeez, that's tough stuff. What do you think caused the bearing failure so quick? Was it a cracked oil feed tube or debris in the oil system or perhaps just a improperly assembled block?

I'm trying to see what the average life of a repair is after a failure. Some say repeat failure is imminent if you don't change out every single oil related component. Not just the oil cooler but oil feed lines, oil pump, avcs oil passages and cam pulley actuators, oil pan and pickup tube.

I'd like to hear of someone getting over 100k miles after a rod-bearing failure repair that wasn't just a longblock swap.
I am in the midst of a build on my 07 Limited due to rod bearing failure (or what I suspect to be)...car has 66K miles on it and has been Stage II (Cobb custom 20 psi tune, CAI, Cattless TBE, APS DR525 FMIC) since 5K miles old.

I ran into an unknown low oil situation due to blow-by combined with a hard downshift caused the failure. I've yet to pull the motor apart but all signs point to a rod bearing. The car ran and drove after the "incident" but had a strong rattling sound.

I got a old but brand new 2010 shortblock from a local rally team with the nitrided crank and a local shop is installing standard bore Mahle's. I wasn't considering replacing the entire lubrication system other than the oil pump, but I too would like to see mileage numbers from members who've reused oil pickups (already have the Killer Bee, along with the windage tray), and the topend parts mentioned.
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Old 11-21-2012, 10:27 AM   #13
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I understand the importance of cleaning and/or replacing the oil pump, oil cooler, etc. when rebuilding a motor with a spun rod bearing, but the fact is almost all spun rod bearings are due to incorrect clearance, heat expansion, or oil starvation; not a piece of debris in the oil getting in between the clearance area . Flame suit on, but it's just a fact.

I've taken apart a many a spun rod bearing motor, ones that were ran a good while after the initial failure. The other surviving bearings did have scuff marks from the debris in the oil, but none ever spun due to the debris.
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Old 11-21-2012, 06:16 PM   #14
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never.....NEVER re-use the oil cooler

and NEVER use any 5w30 oil
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Old 11-21-2012, 06:21 PM   #15
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Quote:
Originally Posted by Zackbo View Post
I understand the importance of cleaning and/or replacing the oil pump, oil cooler, etc. when rebuilding a motor with a spun rod bearing, but the fact is almost all spun rod bearings are due to incorrect clearance, heat expansion, or oil starvation; not a piece of debris in the oil getting in between the clearance area . Flame suit on, but it's just a fact.

I've taken apart a many a spun rod bearing motor, ones that were ran a good while after the initial failure. The other surviving bearings did have scuff marks from the debris in the oil, but none ever spun due to the debris.

the VERY VAST MAJORITY of spun bearings comes from metal to metal contact due to the WRONG OIL BEING USED

this wrong oil shears piss thin and is consumed by the engine through the pcv system...THIS causes knock....the knock then pushes the metal parts together through the sheared oil film in the bearings..

and p0p goes the bearing

all done

the MORAL of this story is this:

USE GOOD OIL THAT WONT SHEAR AND BE CONSUMED AND YOUR ENGINE WILL LAST A LOT LONGER
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Old 11-22-2012, 09:37 PM   #16
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Quote:
Originally Posted by Uncle Scotty View Post
never.....NEVER re-use the oil cooler

and NEVER use any 5w30 oil
On any wrx?? new motor or used/rebuilt??? In winter and summer??
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Old 11-22-2012, 10:13 PM   #17
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Quote:
Originally Posted by Liquid167 View Post
On any wrx?? new motor or used/rebuilt??? In winter and summer??

d00000000000000d....there are SO MANY GOOD oil choices out there that dont involve any 5w30 oil

read...learn...read some more....keep reading until yer eyes bleed

then ya see where im comin from.....a couple of these NEW 'SN' 5w30 oils MAY prove to be OK...but im still not drinkin any of that k00l-aid....not yet

and all of what you are thinkin, above, can be easily handled by something other than a 5w30
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Old 11-26-2012, 10:49 PM   #18
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We specialize in high end foreign cars, mostly benz, BMW, and Porsche and we use either 10w30 motul or 5w30 LiquiMoly, both fully synthetic. It seems to be really good oil, and it meets the warranty spec for those guys, but i always like to get other peoples take on hard to quantify stuff like oil. A lot of people have opinions about oil and like the saying goes, most of them stink. So, any facts, numbers, personal experience would be great. Both my 230k toyota and 240k Tahoe use the sybthetic stuff and run great with it.
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Old 12-12-2012, 06:08 PM   #19
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I am another lucky one who has suffered from a rod bearing failure. I stepped up the ladder. Sold my 02 2.5rs And i needed to go turbo so i purchased an 04 wrx stock with 130k miles in january of 2012. I thought i had it all figured out. Went to get a tune up, through in some 5w30 oil, cuz thats what the manuel said i should use. In march flashed to a cobb stage II ots map, literally a week later, one of the rod bearings went. I heArd that dreaded noise u see on those youtube videos of when rod bearings go... Mind u in NYC traffic. Luckily i was near an exit and got the car towed to a shop. Dont know if it was neglegence on my part or just piss thin oil f**ked me over.
I have now rebuilt the engine with a 2.5L bottom end, machined stock heads (chambers opened up), Mahle stock sized pistons and a 16g. The cars noisy on start up and after it warms up still a bit noisy. So fAr 10k miles on engine & ive been running mostly 15w40 oil. Car made to Arkansas & back (NY) this summer so go figure..
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Old 12-12-2012, 06:11 PM   #20
danger1138
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O yea forgot to mention put in new oil pump, and new oil cooler. Just to be on safe side.
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Old 12-13-2012, 07:59 PM   #21
Maxwell Power
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Let me start by saying that we have had zero bearing failures from engines that we built with our methods. We have hundreds of engines around the globe running for years on high power, high rpm operation with zero failures. The only ones to ever fail are when customers insist on reusing certain parts: Rods, oil pan, oil pump, oil cooler etc.
When we did airplane engines we had NUMEROUS oil pump relief valves stick from small amounts of particulate left over in the oil pan. Regardless of how well it was cleaned, there is ALWAYS metal in it.

If a customer comes in with a spun bearing, we won't work on it until he agrees that he is changing:
Pan,
Pump
Cooler.
All our engine builds use new components so no more worry with resized rods, turned cranks etc.
Heads are disassembled and thoroughly cleaned.

All that is fine and dandy, but the most important part of an engine build is getting the clearance correct. ALL the clearances. The main bearings are more important than rod bearing clearances. When building engines with used blocks the mains are ALWAYS over 3 thou and sometimes closer to 5. If your builder says they aren't, uses HX bearings or something else, he's wrong. In hundreds of cases I have Never ever ever seen a used case come out with proper clearances using standard size bearings. Now some logic has to be used here in that most used cases are over 30k miles. If you have a 5k mile case, then I suppose the mains could still come out. However, we don't get 5k mile cases. I can't imagine many people do.

Now you're probably wondering "wait you said you use all new components, but now you're saying you use used cases".
Let me clarify:
1. For new builds we no longer use old cases. This policy has been in effect for about two years. We used to rebuild a lot of motors but they took more money and time than they were worth.
2. We only use used cases for sleeved, high horsepower cases. In each of those cases we mill the inside surface of the case flat and shoot the mains again. They are NEVER even close to being flat when we get them. This is because the engine has been cycled, seasoned and stress relieved. This is why the mains are always big on used cases. That is the same reason we use them for sleeving. We don't want the cases to wander after sleeving.

Lastly:
DON'T USE 5W-30!! Read the owner's manual. It even says not to use 5w-30 for anything other than commuting and daily driving. If you're trying to make power on 5w-30, you'll be spinning a bearing.
Don't use Mobile 1. Why?
1. Mobile 1 engines are always some of the cleanest engines when we take them apart. No oil residue anywhere. That makes no sense to me. If your oil is adhering to surfaces and providing lubrication there should at least be a little residue.
2. The only engines I have ever seen with bucket or cam failure have been Mobile 1 engines.
3. I have seen oil tests that cover film thickness, viscosity and friction over the temperature and pressure range and that oil just doesn't cut it.

CN:
replace it once or replace it twice
do it right once
don't use 5w-30 or mobile 1
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Old 12-13-2012, 08:23 PM   #22
Bad Noodle
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Quote:
Originally Posted by UK-Wagon View Post
OP,
Did you install a new crankshaft with the second engine? or was it resurfaced?
Also what was the cause of the failure on that second engine??

*To add a note here,
Im a subaru certified tech, for warranty purposes we cant replace many of these parts like, oil pan, oil pump, oil cooler or any of the related lines. We are instructed to flush them and inspect the oil pump for damage. The oil pump can be completely stripped down, cleaned and inspected. If its scored or scratched in the pump housing then yes, it is to be replaced. Ive yet to ever have a engine come back with spun rod bearings for not replacing any of those parts. You just have to have the right parts cleaner and time to make sure it is 99% clean.

I have had 2 engine Ive built come back, but it was many miles later and in both cases they were on the track during the failure.

For built engines, oil clearances and other things cant be put to OE Spec tolerances or clearances for that matter or you will have failures. It takes lots of time and knowledge to get these things correct. I often have to have bran spakin new crankshafts sent out for machining! Yes even the Nitirde cranks are not good enough for me. Many get .005 thousandths removed to get my clearance right where i want it. I dont do this for warranty jobs, but I do for customers that want built engines.

Keep this in mind too, I NEVER trust machined crankshafts for over size bearings in a Performance application. They dont last!!!! New Nirtide cranks are only $325..... Turned/machined cranks after a bearing failure are just worthless and youre asking for it to happen again very soon. Ive got a pile of cranks here going to the scrap yard. Many are saveable for turning but I just dont risk it anymore.
How do you guys clean out the oil cooler? I've argued that it can be cleaned with a combo of higher pressure and super sonic cleaning with degrease. After a thorough cleaning, I was still able to shake particles out ...
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Old 12-13-2012, 08:33 PM   #23
car_freak85
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Quote:
Originally Posted by Maxwell Power View Post
Lastly:
DON'T USE 5W-30!! Read the owner's manual. It even says not to use 5w-30 for anything other than commuting and daily driving. If you're trying to make power on 5w-30, you'll be spinning a bearing.

CN:
...
don't use 5w-30...
So what do you put in YOUR subaru?
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Old 12-13-2012, 08:43 PM   #24
EROCS04SBRUSTI
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I think this is good info!!
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Old 12-13-2012, 09:02 PM   #25
john 1badSTI
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on e85@ 30psi--spinning

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Dom as always is spot on with his info and I think he will agree that a lot of the spun brgs are also due to tunes,all it takes is 1 bad incidence of det and bamm the oil cushion gets pushed out due to the increased cylinder pressure from the det and you get metal to metal.Once this happens the brgs life goes down hill quick,once the damage is done its done,it just gets worse.
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