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Discussion Starter #1
A well maintained vehicle. I noticed a buzzing (or lug) noise when at lower speeds upon acceleration. I had the mechanic check it out. Initially he was not sure. No engine codes show up. Recommended 91 Octane fuel, which we already do. Kept making the noise. Brought the car to a dealership and they suggested replacing the spark plugs. It was noted it misfired on 2 & 6. (mechanic who specializes in repair service thought this was not necessary and would not fix the problem) We spent the money and replaced the spark plugs hoping it might. The vehicle still has the same issue. The mechanic does not do the work that potentially might need to be done to correct the issue. (Thought it might be a torque converter). Which we are not sure if that is even the issue? I put very little miles on the car. About 6,000 a year. Here's my question.
If I was to have a torque converter replaced, would it be advantageous to have the head gaskets replaced, timing belt, etc. at the same time as it appears a torque converter has to have the engine lifted? I could be wrong with this. Just trying to do the smart thing overall for my pocketbook. It has 105,500 on the car. Any advice would be appreciated.
 

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I simply cannot abide useless people.
2006 2.5i and 2002 3.0 wagons.
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H6 does not have a timing belt or HG issues.
 

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2008 3.0R
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it's an h6, it uses a timing chain which (for all intents and purposes) should last the life of the engine

the h6 is not known to have head gasket issues. unless you are having issues, replacing a head gasket is pointless
 

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Discussion Starter #4
Thanks for the clarification. Does what I am describing sound like a torque converter?
 

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2006 OutBean, 2005 LGTW
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Does your car make the sound across the entire RPM range or is it just a certain RPM range. I wonder if it's a resonant frequency thing with a exhaust heat shield or something.
 

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Discussion Starter #6 (Edited)
It makes the sound when the speed is lowered. If I slow down and then accelerate that's when you hear it. Not every time but often. It's like a shudder feeling with that noise.
 

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03 H6 OBW & 06 WRX Sportwagon
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heat shields are notorious for buzzing.

make sure the front diff has the proper lube in it - GL-5 (synthetic is OK) - easy for non-Subaru experienced folks to drain/fill the wrong components/fluids.

have you tried the FWD fuse (I THINK the 5EAT has one, not sure)
 

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18 horizontally opposed cylinders of fury
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Is it exclusively a sound/noise, or is there something you are feeling as well? I have the same car, the exhaust heat shields (like pretty much all Subarus) eventually rust enough that they rattle. That's just noise, you don't feel any vibration, & it's most noticeable at lower RPMs & lower speeds & specific throttle application.

Spark plugs could have been original, so they were due for replacement. If done at a Subaru dealership, they should have used the OEM specified NGK ILFR6B. Other plugs may fit but could be prone to misfire.

If you are *feeling* vibration, though, there is an acknowledged design issue with the torque converter on 08 & early 09 cars with the 5-speed automatic. I'm pretty sure I have it but my car was well out of warranty before I learned about it. Look for my post in this old thread, I linked to the Legacy forum where you can read the TSB. It occurs at light throttle in gears 3/4/5.

There's noise with this issue, but the vibration is the more noticeable aspect. If you have only noise, this probably doesn't apply, but it's curious that a dealer service person would focus on the TC with the small amount of diagnostics you've described.

Try switching your SI-Drive to S# for the day & see what's different, besides markedly better performance ;) S# controls the TC differently with the result of mostly mitigating the issue described in the TSB.
 

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Discussion Starter #9
Mr. Ed-the thread you sent me to described exactly what the car does.



There's noise with this issue, but the vibration is a very noticeable aspect. The Dealership wrote when I brought it in that it was tested with SSMIII and noticed it. Noted two misfires on #2 and #6 cylinders. Noted a shudder one time which felt like a Torque Converter Shudder. Checked fluid levels and condition and both seemed fine. Suggested Spark plugs and replaced with 6 22401AA630 Spark plug. They drove for 7 miles with no misfire after plug replacement. Unfortunately, it did it for us right after and ever sense.

We have tried switching SI-Drive to S# and it is a little better at times but still does it. It is very annoying.

Any ideas on what a torque converter replacement might cost?
 

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18 horizontally opposed cylinders of fury
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Retail on the corrected TC (p/n 31100AB132 for H6) is $677 while the online discount dealers have it for around $550. Replacing would entail a full fluid change so that's X quarts of fluid. There may be ancillary parts (seals, one-use nuts & bolts, stuff like that) but the killer would be labor if you aren't able to do it yourself. It's a complex job that includes pulling the engine.

You could make a case for some assistance from Subaru, especially if you have a diagnosis from the SSM matching the symptoms & measurements spelled out on the TSB. They might help with parts cost, but probably not with labor.

I still might replace my TC someday, my 08 only has 65k on it & it's no longer my daily driver, so I could do it myself regardless of how long it takes. It is disappointing that Subaru's top of the line models from 08-09 had such a fundamental engineering oversight- which they acknowledged.

So far I just tolerate it by modulating the throttle, using S#, and/or manually downshifting & upshifting. I retrofitted the paddle shifters from an H6 Legacy & that makes it easy to blip a gear change.
 

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Shudder is noticeable. Will happen under light throttle load when the car is warm. If you give it gas when it's happening, the car will upshift and be back to normal.

Annoying, but also not terrible. Fix the misfire though.

I retrofitted the paddle shifters from an H6 Legacy & that makes it easy to blip a gear change.
Any more info on this?
 

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18 horizontally opposed cylinders of fury
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Any more info on this?
I have a photo write up in the link in my sig. It's a fun project & a nice addition. When I did this a few years ago the paddle assembly was a non-stock item, so it took a few months for enough orders to roll in for Subaru's US parts people to get them from Japan. You might luck out or maybe find a decent one in a boneyard Legacy.
 

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2006 Outback LL Bean H6. Ivory interior, Moss green exterior. 132K
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It's a complex job that includes pulling the engine.

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Mr. Ed, you have to pull the engine to replace the TC? I would think the transmission would be easier to remove, no?

Cheers,

John
 

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You are correct about dropping the transmission. I read the FSM procedure once but I must have been confused with some other complicated repair. It still looks like a lot of steps & lots of things to do carefully & correctly. I wonder what the book rate is to replace a TC on our cars?
 
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