My 2003 Outback Wagon is Junk!, revisited.

[rem14]

Hi All. Well they replaced numbers 2&3 pistons 3,000 miles ago due to excessive clearance and they said all was good. Mind you the car now only has 36,000 miles on it. The car has been carefully driven and oil changes and maintenance have been religiously performed. Subaru, as a good will gesture gave us back the money we spent on the 30,000 mile service which was approximately $400.00, which I thought was VERY nice. I took the car back for an oil change at 36,000 miles and guess what??!! Number four piston is now making that wonderful tap, tap , tap noise! Our dealer called today and said Subaru OK'd a new short block to be insalled. Just wondering what you all think and comments. Should this thing last awhile or should I trade it off??

[mattocs]

Hi All. Well they replaced numbers 2&3 pistons 3,000 miles ago due to excessive clearance and they said all was good. Mind you the car now only has 36,000 miles on it. The car has been carefully driven and oil changes and maintenance have been religiously performed. Subaru, as a good will gesture gave us back the money we spent on the 30,000 mile service which was approximately $400.00, which I thought was VERY nice. I took the car back for an oil change at 36,000 miles and guess what??!! Number four piston is now making that wonderful tap, tap , tap noise! Our dealer called today and said Subaru OK'd a new short block to be insalled. Just wondering what you all think and comments. Should this thing last awhile or should I trade it off??

 

Possibly a lemon? Check with some lemon law attoneys...you might be able to sue and get your money back for the car.

[Cougar]

If they put a short block in that should totally eliminate the original problem. It sounds to me that Subaru is trying to do what they can for you on this. You will basically have a rebuilt motor when done.

[mrk610]

Take the short block .I have had my #2 and #4 pistons replaced in Jan 04 for piston slap . It sounded great untill this winter . Now I have the knocking back . Not nearly as bad as before the piston transplant . I'm going to have it looked at again , but I know there answer as long as the noise goes away it is normal.

When I had the pistons replaced the noise never went away . I have a 7year 100k sub gold warranty given to me by SOA as a good faith gesture . I have also noticed that I am now burning a 1/2 quart of oil between changes . My car never burned oil. Ohh by the way i have an 02 outback with 53 k miles on it .

 

Good Luck

MIke K

[Scoobaroo]

This piston slap thing is a "Cluster F.....".

 

When these engines are new, the piston-to-bore clearance is around 2 thousanths of an inch or so and all is well (and quiet.)

 

The problem is that 2 thousanths of an inch quickly becomes 4,5,or 6 thousanths of an inch clearance due piston skirt scuffing. There is no way that a piston with skirts as short as the 2.5 has can ride squarely in the cylinder with 5+ thousanths clearance.........ain't gonna happen.

 

On the other hand...........fitting brand new pistons tighter at the factory could lead to piston seizure. (Not an option).

 

Due to the bore and stroke measurements of the 2.5, it's almost impossible to engineer a piston with skirts longer than the present ones. (Also not an option).

 

You could change your oil every day and it wouldn't help.

In a nutshell, a 2.5 almost can't have quiet pistons for more than 20k or 30k miles if you live in a cold climate.

 

Your new short block will have "the slap" again in 30k miles.

[blitz]

The 2.5 piston is barrel-shaped, it's designed to rock in the bore a small amount. The only thing that happens after 20-30k miles is that the moly-coating wears away, unmasking the noise, the rocking motion itself hasn't increased appreciably. The noise is part of the design, either you successfully come to peace with it or you don't.

 

"Countermeasure Piston" is code for: same piston, only with moly-coating intact, for another 20-30k relatively quiet miles. It quiets a noisy customer.

 

I've noticed a tendency for manufacturers to buy time by issuing bogus "revisions", e.g. 4 revised headgasket specs for the 2.5 II - each one failing at the same rate the previous one did and for good reason: it is the same one.

 

4 "revised" versions of the Cobb header, each new version cracking like the previous version. Ad infinitum.

[Scoobaroo]

The only thing that happens after 20-30k miles is that the moly-coating wears away, unmasking the noise, the rocking motion itself hasn't increased appreciably. The noise is part of the design, either you successfully come to peace with it or you don't.

 

 

Agreed. The moly coating is only there to sell the car since nobody would buy a piston slappin' car brand new off of the lot.

 

The rocking motion does increase some because the moly coating is a few thousanths of an inch thick. When it scuffs off, the piston skirt is smaller by a few thousanths. The increased rocking motion scuffs even more material from the skirts until your 3 year old Subaru has the piston-to-bore clearance of a 40 year old Mexican school bus.

 

Car companies are good at covering their f-ups with slick sounding TSB's.

 

".........the knocking sound is a characteristic of a low friction engine design............the noise won't affect engine performance or longevity........."(blah, blah, blah.)

 

(Translation) it would cost us a $hi%load of money to deal with the head gasket and piston slap issues. Let's add a bottle of sealer and print a 3 cent piece of paper telling people that the slap is "normal".

[cookie]

I liked the "quiets a noisy customer line."..He He He. I would like to see a comparison of the counter measure piston next to a regular one to see if there are changes myself.

I have seen photos of Subaru head gasket versions on the web that were different. They just didn't work much better than the originals, which must mean Subaru's testing was not that great.

As for this car I think the guy is getting great deal with a new short block. I have just learned to live with mine. It is pretty tolerable with the current heavy oil, but that is sure not an option at 20 below zero.

[blitz]

Agreed. The moly coating is only there to sell the car since nobody would buy a piston slappin' car brand new off of the lot.

IMO, the proof in the pudding is the coincidental appearance of moly-coating ON slappers. The GM slappers sport the moly-coating too, no?

[blitz]

I would like to see a comparison of the counter measure piston next to a regular one to see if there are changes myself.

IMO, the fact that Subaru often elects to replace only the two noisiest of four in a given motor is what makes me think it's the same part. Somehow I can't envision pistons that were substantially different being mixed together. I dunno, maybe I'm daffed.

 

I have seen photos of Subaru head gasket versions on the web that were different. They just didn't work much better than the originals, which must mean Subaru's testing was not that great.

The twist here lies in the fact that the, gasket isn't really the problem ...the thin (overbored), unsupported (open-deck), "walking" bores are. Another ploy ...the "straw man" fix.

 

I have just learned to live with mine. It is pretty tolerable with the current heavy oil, but that is sure not an option at 20 below zero.

I just accept it too, I don't like it tho. I think that choosing oil on the basis of slap may not be the best route to choosing oil. You'd be buying into more straw-man logic (the oil's not cause of the slap, therefore it isn't the fix).

[cookie]

Yep,

 

Given a non slapping motor I would go with a lighter oil as I do in my BMW. I forget what's in there at the moment but it is a light multi grade Mobil 1.

I am sure I am sacrificeing some possible fuel mileage with the 15-50 Mobil 1 in my old Forester, but it seems to run about the same around here as 10-30 dino.

On the head gasket problem....

I also think that the overbore and open deck is the real problem and the gasket just treats the symptom.

Regardless it is possible to get a lot of mileage out of these engines slapping happily away. Could subaru have done better? Yep, and engines like the old 2.2 prove it. I never seem to hear of much for problems with WRXs either, unless it is owned by a kid who beats the %%&& out of it.

[rem14]

Thanks for all the reply's! The winter was pretty cold here in western PA this year. There were times it sounded like that engine was just going to come apart! Would using synthetics after engine break in help to prolong the reaccurance of the slap?

[cookie]

Now we will get into opinion here, and I think synthetics are a bit tougher, stick longer, and offer more cushion. If I were you I would go to a synthetic right after break in.

I'm sure others may feel differently.

[rem14]

I was wondering if you are more prone to leaks when using synthetics? I used Mobil 1 in my 97 4.0 liter Jeep Wrangler and the rear main seal developed a massive leak at 19,000 miles.I know that seal was a problem with that engine though.

[Scottbaru]

I know this is taboo among most purists, but what about adding moly additive? One of my brothers is a diesel engine guru, his group runs heavily instrumented diesels. He's seeing significant performance increases with moly additive on several engines. He's definitely an automotive purist, but has changed his thinking on moly. Some moly additives are apparently better than others, it sounds like smaller particles are better and safer for engines. Mr Moly is his current favorite. He hasn't talked me into using it yet, but if I had piston slap I'd have it in immediately.

[Scoobaroo]

The GM slappers sport the moly-coating too, no?

 

Yes.

[friendly_jacek]

I know this is taboo among most purists, but what about adding moly additive? One of my brothers is a diesel engine guru, his group runs heavily instrumented diesels. He's seeing significant performance increases with moly additive on several engines. He's definitely an automotive purist, but has changed his thinking on moly. Some moly additives are apparently better than others, it sounds like smaller particles are better and safer for engines. Mr Moly is his current favorite. He hasn't talked me into using it yet, but if I had piston slap I'd have it in immediately.

 

You don't have to add moly additives to get moly to your oil. Many modern oils come with moly as a part of friction modyfier package. Mobile 1 has modest amount of moly and redline sports a hudge dose of moly. Note that those oils are at the same time big slap offenders and making slap worse by many accounts, so moly is not an answer here.

[Scottbaru]

Many modern oils come with moly as a part of friction modyfier package. Mobile 1 has modest amount of moly and redline sports a hudge dose of moly.

Where did you get that info? I've followed fierce and technical debates about moly on various forums, I'd think that'd raise an enormous stink among those groups. I've used Mobil 1 for decades, but would stop if they added moly. Unless I had piston slap.

[Meeky Moose]

its not just subaru engines either that slap..

 

lol if you all heard my toyota you'd all wonder (how the hell does that thing run)

 

slaps so loud, it sounds like a rod going to come through the side at any moment.. but its been doing that for well over 100K and never even flinches.. truck has 236k on it now and is a daily driver..

 

so i'd say get your new shortblock and if the slap coems back, just live with it..

just my .02

[friendly_jacek]

Where did you get that info? I've followed fierce and technical debates about moly on various forums, I'd think that'd raise an enormous stink among those groups. I've used Mobil 1 for decades, but would stop if they added moly. Unless I had piston slap.

 

Now, the moly in mobil 1 or other fine oils is in soluble form and not particles that can clog your filter as in some third party additives. As for proof, check VOA on Mobile 1 posted on any oil discussion group. I would be happy to post a link but setright would be offended by any mention of cough...BITOG...cough.

[cookie]

I admit I have thought of adding moly to my oil. At the moment its working pretty well and my oil use has gone down so I,m leaving it alone.

Seals were a big issue a few years ago when adding synthetic as it does seem like the particles are finer and the large amount of detergent eats up deposits that may be sealing an old engine. I am not sure I would want to try it with an old engine that had not been resealed, even though they say that sealing is no longer a problem.

[firstwagon]

I was wondering if you are more prone to leaks when using synthetics? I used Mobil 1 in my 97 4.0 liter Jeep Wrangler and the rear main seal developed a massive leak at 19,000 miles.I know that seal was a problem with that engine though.

 

How hard (or expensive) was it to fix the main seal on your jeep? My wife drives a 95 Grand Cherokee Laredo 4.0 and it has the same leak. I was ignoring it but it seems to be getting worse and I guess I'm going to have to get around to fixing it now before all the oil ends up on the driveway.

[rem14]

I really don't know what the cost was because they fixed it under warranty. Good luck!

[blitz]

Where did you get that info? I've followed fierce and technical debates about moly on various forums, I'd think that'd raise an enormous stink among those groups. I've used Mobil 1 for decades, but would stop if they added moly. Unless I had piston slap.

Complete Mobil 1 VOA compilation:

 

http://theoildrop.server101.com/ubb/ultimatebb.php?ubb=get_topic;f=11;t=000305

 

MO = Moly

[jcase321]

Take the new short block. The car is under warranty and let Subaru do the job now. It also gets your car in the record books so that Subaru is aware of the replacement of the engine. You should be good after that. The lemon laws would apply to the same problem 3 times. But since Subaru is willing to put a new or rebult engine in that will fix it. The reliability of Subaru is excellent, so this must have just been crap luck. I have a 2001 Outback with 113K on it now and have done routine maintenece ONLY. Not a dime was put in to any repairs. Eveything original...

 

Hi All. Well they replaced numbers 2&3 pistons 3,000 miles ago due to excessive clearance and they said all was good. Mind you the car now only has 36,000 miles on it. The car has been carefully driven and oil changes and maintenance have been religiously performed. Subaru, as a good will gesture gave us back the money we spent on the 30,000 mile service which was approximately $400.00, which I thought was VERY nice. I took the car back for an oil change at 36,000 miles and guess what??!! Number four piston is now making that wonderful tap, tap , tap noise! Our dealer called today and said Subaru OK'd a new short block to be insalled. Just wondering what you all think and comments. Should this thing last awhile or should I trade it off??