My experience with 15w-50, not good.

[Dickensheets]

Over the last year I have tried various oils in an effort to quell the can of gravel noises (piston slap) I get from cold starts. 97 OBW auto, 110000 miles.

 

My latest experiment was with straight 15w-50. It's not reccomended and now I know why. My avg mpg went from 24 to 19, and the car felt sluggish and didn't rev as freely (thick oil). It also caused shifting anomalies I think because the throttle position sensor was not matching mapped revs, or something like that? But boy was it quiet in the morning.

 

So far the best mix has been: 4qts 10w-30 and ONE qt 15w-50.

 

Ryan

[Smpol19]

 

So far the best mix has been: 4qts 10w-30 and ONE qt 15w-50.

 

 

Both the 2.2 and the 2.5 take 4.2 qt. of oil, you may want to be careful overfilling by .8 qt.

[rlsimpso]

Are you using synthetic oil? I ran 15-50 for serveral years (about 70000 miles) in my Mitsubishi when it started drinking 5-30. I found synthetic oil did not affect the performance at all, whereas the dino oil did. Just my 2 cents.

[jasinwa]

Are you using synthetic oil? I ran 15-50 for serveral years (about 70000 miles) in my Mitsubishi when it started drinking 5-30. I found synthetic oil did not affect the performance at all, whereas the dino oil did. Just my 2 cents.

 

did you mean you ran 15-50 synthetic?

 

Did you have to do anything (some type of flush, etc) before switching from standard to synthetic oil?

[rlsimpso]

Yes, I ran Modil 1 synthetic 15W-50. It supposed to be compatible with non-synthetic oil.

 

This is a long story, but I will be brief.

 

I kinda did a flush when the idiot at the oil change place didn't do a good job putting a filter on and 4 quarts of oil sprayed all over the inside of the engine bay. I decided no more idiots working on my cars. I am stupid enough to do it myself:) .

 

I put the money saved by doing the changes myself in to better (presumably) oil.

 

Mitsu's have problems with valve guide wear and they start to burn a lot of oil. The burning oil makes nice blue smoke and an odor.

 

The "flush": I started out with Mobil 1 5W-30 and all was well, no smoke. The oil consumption was still high, 1 quart every other tank of gas, about 500 miles. I then went to 10W-30 thinking it would do better. Slightly but not much. All the while I added about 10 quarts in addition to the 5 at each change. On the third change I went to 15W-50. The oil compsution went to about 1 quart every 1000-1500 miles. I ran it like that until I replaced the head. Now I am back to 5W-30 Modil 1 and all is well.

 

Besides the lack of smoke, the biggest difference I noticed was the change in cold morning starting. The started worked much less to turn it over and consequently it started faster. Even with the 15W-50 it had not trouble.

 

I also changed the gear oil out for synthetic and cold trans shifts are much better.

 

I have run Mobil 1 in my Legacy and BRAT since I got them and have no problems.

[Dickensheets]

Both the 2.2 and the 2.5 take 4.2 qt. of oil, you may want to be careful overfilling by .8 qt.

 

Actually mine takes exactly 5 qts. Unless the dipstick is bad - but it looks to be OEM.

 

rd

[shaggy ant]

There are two different oil pans. the square bottom one (4.75Qts) and the round bottom one(4.25Qts). The DOHC 2.5l engines all have the square one to my knowledge. The round ones are on 2.5 SOHC and late model 2.2l (95-on) 2.2l prior to 95 had both of them and I haven't figured out the rhyme or reason to that one yet.

[shaggy ant]

Also, you should be filling to the hole not the notch in the stick. Make sure you let it sit for a minute before checking. It takes a while for the oil to drain from such a flat motor.

[christmas22]

Has anyone tried that Royal Purple Oil? I was watching some auto shows, and thats what they used, they swore by it, but I have never tried it.

[subiefan]

My '93 runs Castrol GTX 20W-50 and likes it. Not much difference over 10W-40, just quiets the various noises of a 192k mile engine. Probably burns less too. That's in the summer, of course. I ran 10W-40 last winter; will probably run 10W or 5W-30 this winter. Starting was a bit...interesting when the mercury dipped below 0, especially before I replaced my battery. Can anyone say rrruh....rrruh.....rrruh?

[Setright]

I have very positive results running Mobil Delvac 1 5W-40 in my engine.

 

I can't work out the exact circumstances, but half the mornings the is no audible piston slap. Other mornings, it's very dulled and goes away fast.

[blitz]

I've always held the belief that a little reserve viscosity was a smart hedge against cooling system failure or fuel dilution, etc.

 

Now that it's become unfashiopnbalble (sp.?) to use a lube with even the slightest amount of meat on it's bones, I'm completely determined to use a heavier oil, just for the hell of it. :-p :cool: Where's my parachute pants?

 

C'mon, isn't anybody gonna get really pissed-off at me? Argg...

 

**** ******!

[itzed]

I have very positive results running Mobil Delvac 1 5W-40 in my engine.

 

I can't work out the exact circumstances, but half the mornings the is no audible piston slap. Other mornings, it's very dulled and goes away fast.

 

I come from a VW/Audi background, and I only have about 400 miles on my new Legacy, so I'm far from familiar with Subies. But I do have some rather extensive information on oil as VW has stringent tests and recommendations that Subaru apparently does not have. They, and most European manufacturers almost exclusively recommend 5w40 oils for year round use. I really don't see how you can go wrong with most any oil that meets VW's 502 standards.

I've got a lot of documentation on this if anyone is interested, but for now, here's a list of the North American oils that meet it:

 

 

Ed

[Manarius]

I've run 20-50w year round now for 2 years. In the summer, I can almost break 23 MPG with a EJ22 and 4EAT. In the winter, it hovers around 20-21 MPG. And that's with a pedal happy teenager behind the wheel.

 

If I run lighter oil, it just leaks out all over the place. Darn you crank gaskets.

 

BTW, my car takes 4.6qt because I have the square pan

[cookie]

I've been running Mobil 1 15-50 in my 128,000 miles Forester for over a year now. The only difference is less piston slap and longer OCIs. There might be some fuel mileage penalty but it does not show up in my use.

The oil reports are very good, but they were not bad before.

[subie94]

My '93 runs Castrol GTX 20W-50 and likes it. Not much difference over 10W-40, just quiets the various noises of a 192k mile engine. Probably burns less too. That's in the summer, of course. I ran 10W-40 last winter

 

i too have been running 20w-50 in my ej-22 for a better part of 6yrs now and haven't had any problems..10w-40 in the winter.

 

i did a switch from walmart oil to castrol to see if it controls the leaking.at times i was replacing about two guarts every other week..

 

[porcupine73]

I've been running Amsoil TRO 20W-50 racing full synthetic with a little TSO 0W-30 since last winter; no issues at all. Engine cranked a little slower in the cold....Buffalo NY weather, but started every time. Engine is much quieter on this heavy oil; no noted change in mileage [was running Amsoil HDD 5W-30 before]. Just got 30mpg! a few weeks ago on a 300 mile trip hauling 4 people through some PA hills. 2000 Legacy Outback Wagon 2.5L auto, 105k miles. I also switched to Amsoil SVG 75W140 in the diff's; no change noticed. --Louis

[Gnuman]

197K miles on my 92 EJ22. What are these noises that you are talking about (saying that they are expected)? My engine is nice and quiet, and I use about .5 to 1 qt in 3K miles. The clutch died (the cheaps**t clutch is not as strong as the engine, and spins on hard launches. This burns the disc material prematurely. Never never NEVER put a "Duralast" clutch in a Legacy. . .) so I'm doing the scheduled 200K service 3K early. I will be going to synthetic after I replace all the seals along with the timing belt, waterpump, headgaskets (I wanna take a look at the cyl walls) and crossover pipe O-rings. I spend so much time and attention on other Subarus (they need it a lot more) that I'm sure emily will get jealous if I do not give her some time as well. . .

 

Oh, and the clutch I'm putting in is from a tunered 2.5L Impreza, and comes with a drilled flywheel. It is my guess that a clutch made to keep up with a 160HP engine should have no issues with a 130hp one. ..

If the disc dies on this set (only 40K on the engine when the driver lost it and smashed up the rear end), I will replace the disc and keep the Pressure plate.

 

For viscosity, I use cheap 10w30 dino, right now, and no significant noise from the engine ( I can even hear the injectors cycling)

[SaltCar]

The search function is a wonderful thing.

 

http://www.ultimatesubaru.org/forum/showthread.php?t=55506