The dealer/shop told me two things...

First of all, as many of you have noted, they feel this is normal Subaru engine behavior; it is the sound of the lifters. Gold star for the guy that diagnosed this earlier.

Second, the reason I am hearing it is not just because the engine is getting colder than before, it is because I switched to all-synthetic oil which has a lower viscosity and less sound- and vibration-damping ability.

I HATE the sound, however! It is loud enough that neigbors and co-workers turn their head as I go past. I feel like I am driving a Ford Model T...

Price you pay for synthetic oil?

 

Please try my experiment, and see if its not the injectors. Have you ever actually tested this?

AFAIK, noisy lifters is never a healthy symptom. An affectation of synthetic oil? I certainly hope not. That would mean that synthetic oil protects less (against shock) than dino oil. If that were the case I'd think it useless, despite its resistance to breakdown.

jason

 

I thought EJ20 was a solid-lifter valvetrain....so it cannot be a case of hydraulic followers not boosting up.

 

The mechanic I talked to said that he has 17 years experience working on Suby boxer engines, and they all clatter in cold weather. However, he does work for a dealership, so perhaps he's just hoping to charge me top $$ to rebuild my engine after it passes the 36,000 mile warranty :-)

I'm certainly not a lubrication expert, but it is my understanding that the lower viscosity of lubricant, the better; the lack of surface tension allows it to get deeper into smaller pores and cracks in engine surfaces -- and your pistons do not have to "fight" as much drag from the oil. Switching to full synthetic gave me an instant mini-power boost (according to my butt dyno).

Anyway, I have it in for service on Monday to fix a rattle behind the dashboard, so I'll corner one of the grizzled older mechanics (rather than the chap who works behind the service counter) and press them on the issue.

 

5w30 is 5w30. Synthetic or dyno. I think your butt dyno is off Weight is weight and viscosity is viscosity, per its rating. If it was different, they would label it differently. The difference between similarly rated dino and synth is propensity to break down and not provide proper protection as heat increases.

jason

 

I totally agree... but what's the clacking when its not cold <singsong>no one's trying "my" experiment</singsong>

jason

 

Oh yes, I know the way oil is graded/labeled. I did in fact switch to a lighter weight when I went full syn. However, the syn oil does (according to some brochure!) have a smaller size at the molecule level, and to my fingertips seems to feel "thinner." It also seems to get dirty faster, or perhaps because of its lighter color shows the gunk more.

To be honest, I haven't tried your test because I don't own a long-handled screwdriver ;-). I'll try it with the tire iron, any long piece of metal should do the trick.

 

Oh my God, be careful hahaha... no posting pics of holes in your head! Sudden jerk of the engine...

jason

 

its ur lifters... when its cold they are small and when they heat up they get to their operating size and fill up the gap. the gap when its cold makes them go click click click when the metal hits.

 

is it when you just start up? I would tend to think it's normal when the engine is just started up when cold. Mine does it for a few seconds at that point. I have an '04 WRX.

 

I have the same Problem i am thinking that my Exaust is the culpe-RAT iam thinking that there is a small gap and it heats up it seals it plus i was doing some work on my Engin put in new valves and i swear i dident have this before but i think eather the lifter or my exhaust its bothering and it is coming from under the turbo on my 04 WRX WAGON I i would still think that it should not be the lifters Just because not all cars have the isue and alot of people might have had there Exhast down pipes and sooo on workd on and prob like me dident replace the metalic gasket soooo HERRRS HOPING ill keep you guys up to date I am pretty much a Family taught Mechanic soo it will take me a good 4 hours to fix this problem if it is the Exhoust soooooooooooooooooo i hope this helps someone but not untill i doo the work maybe this week end or next SUBe UP and out!!