Viscosity suggestionsfor old Subaru

[Crab]

So I bought this old 2002 Subaru with 160k miles on it... still not sure why I bought it. Since the weather in the N.E. has turned cooler The 2.5 EJ engine has developed a mild knock until the car warms up, then it goes away. I found out that this is normal for some of the older Subarus because the piston design (shorter piston skirts) was changed for economy.
My question is, what is the best oil to use for this engine especially in the winter for cold start protection and to help with the piston slap. Thanks CRAB

 

[Trav]

0w40 or 5w40. A lot of people like Rotella T6 in these engines, I tried Mobil 1 0w40 and the Rotella and don't find much difference.
If you live somewhere where it gets colder than a witches hand then maybe but not PA.

 

[zach1900]

I wouldn't call it knock as that more refers to a bearing. Pistom slap maybe which is usually harmless especially when it disappears after warm-up. Just ask any GM V6 owner. Oh sorry just saw you did refer to piston slap.

 

[Padawan]

I generally use a 10w30 or 5W-40 HDEO (usually Rotella) during the winter months in ours.

One other thing I know many folks here dismiss but that I personally stick to is using an oil filter with the proper Subaru-spec bypass pressure.

 

[ARCOgraphite]

Use the Subaru filter and We used to run 1/2 5w30 and 1/2 10w40 either Formula Shell or Mobil clean 5000. Maintained fuel mileage and solved engine racket.
I don't see the need for 100% 40 grade.
Absolutely no need for syn in this engine.

 

[webfors]

Old H4 ej25, use whatever is cheapest. The piston slap is harmless especially since it goes away after warmed up.

 

[Hollow]

Piston slap is common and harmless.

Our Subaru (2003 with 155K or so) has run the quietest on Pennzoil Conventional 5w30, Quaker State Ultimate Durability 5w30 with some MOS2 thrown in, QS Defy 5w30, Pennzoil High Mileage 5w30.

Basically, something on the thick end of a 5w30 and with a good dose of Moly.

 

[Branson304]

Originally Posted By: Trav
0w40 or 5w40. A lot of people like Rotella T6 in these engines, I tried Mobil 1 0w40 and the Rotella and don't find much difference.


+1

 

[05LGTLtd]

I'd consider a HM 5w30 for the winter. First it has seal conditioners, which is a good thing in old boxer engines. Second it is a tad thicker so might quiet some of your piston slap.

Had a 2002 Forester, think I mostly ran GTX 5w30 at the time, maybe Pennzoil conventional. Traded it for the LGT after a few years.

 

[Crab]

I did change the oil on Monday and I used Castrol high mileage blend 5w30 and added 18oz. of Lucas oil treatment and a Wix filter. I bought the blend by mistake thinking it was dino. I do have Subaru filters that I use on the wife's Outback, I never gave thought to use one of the Subaru filters on this car.

 

[Trav]

Originally Posted By: Crab
and added 18oz. of Lucas oil treatment

The HM blend is no problem but this stuff was a waste and just tainted perfectly good oil.

 

[bluesubie]

Originally Posted By: Trav
Originally Posted By: Crab
and added 18oz. of Lucas oil treatment

The HM blend is no problem but this stuff was a waste and just tainted perfectly good oil.

And

to Genuine Subaru Piston Slap. None of the oils that I tried made a difference in my wife's '99 Outback. Valvoline conventional 10W30/10W40, Max Life 10W30, Euro Castrol 0W30, and a few others.

 

[Crab]

Originally Posted By: Trav
Originally Posted By: Crab
and added 18oz. of Lucas oil treatment

The HM blend is no problem but this stuff was a waste and just tainted perfectly good oil.


Lucas products are popular around here, so I thought I'd try it. So your sayin' I wasted $9 and it does no good at all?

 

[WankelRotorHead]

Originally Posted By: Crab
Originally Posted By: Trav
Originally Posted By: Crab
and added 18oz. of Lucas oil treatment

The High Mileage blend is no problem but this stuff was a waste and just tainted perfectly good oil.


Lucas products are popular around here, so I thought I'd try it. So your sayin' I wasted $9 and it does no good at all?

It increases the viscosity of your oil...that's it

I'd run a High Mileage oil from any of the major companies...Castrol, Pennzoil, Valvoline, Mobil, etc to keep those boxer engine seals conditioned. 5w30 should work just fine.

 

[Garak]

Originally Posted By: BikeWhisperer
It increases the viscosity of your oil...that's it

And reduces the concentration of the additive package. If one wants thicker, by a thicker oil.

 

[BrocLuno]

Yeah, adding Lucas Oil additive is just adding PIB and some other bits to thicken the oil... I'd suggest just using Valvoline MaxLife 10w30 and a good filter (Baldwin, WIX, Etc.). Let it idle for a few minutes to get some heat down to teh skirts so they expand and then drive away. At 166K, it could use High Mileage oil for the properties noted above

 

[riggaz]

This is the laughable write up of all the recommended lubes on my data system, i like the fact they are all there but...

Engine oil (Preferred specification) CCMC G4 SAE 5w30 Below 40 °C
Engine oil (Preferred specification) CCMC G5 SAE 5w30 Below 40 °C
Engine oil (Preferred specification) ACEA A1 SAE 5w30 Below 40 °C
Engine oil (Preferred specification) ACEA A2 SAE 5w30 Below 40 °C
Engine oil (Preferred specification) ACEA A3 SAE 5w30 Below 40 °C
Engine oil (Preferred specification) API SJ SAE 5w30 Below 40 °C
Engine oil (Preferred specification) API SL SAE 5w30 Below 40 °C
Engine oil (Alternative specification) CCMC G4 SAE 10w30 Above -20 °C
Engine oil (Alternative specification) CCMC G5 SAE 10w30 Above -20 °C
Engine oil (Alternative specification) CCMC G4 SAE 10W-40 Above -20 °C
Engine oil (Alternative specification) CCMC G5 SAE 10W-40 Above -20 °C
Engine oil (Alternative specification) ACEA A1 SAE 10w30 Above -20 °C
Engine oil (Alternative specification) ACEA A2 SAE 10w30 Above -20 °C
Engine oil (Alternative specification) ACEA A3 SAE 10w30 Above -20 °C
Engine oil (Alternative specification) ACEA A1 SAE 10W-40 Above -20 °C
Engine oil (Alternative specification) ACEA A2 SAE 10W-40 Above -20 °C
Engine oil (Alternative specification) ACEA A3 SAE 10W-40 Above -20 °C
Engine oil (Alternative specification) API SJ SAE 10w30 Above -20 °C
Engine oil (Alternative specification) API SL SAE 10w30 Above -20 °C
Engine oil (Alternative specification) API SJ SAE 10W-40 Above -20 °C
Engine oil (Alternative specification) API SL SAE 10W-40 Above -20 °C

I think someone had too much coffee

 

[Crab]

Thanks Everybody. I'm just going to eliminate the Lucas and use good High Mileage oil and the proper Subaru oil filter. I know the piston slap is normal, but it is extremely annoying in the winter. I thought maybe someone here may have found a cure for the "Subaru Slap".