I currently have 10w 30 mobil 1 synthetic oil in my ea81. Is this a good oil type and weight to be using in this engine with 200k miles, or is there a better oil to be using?

 

I want this engine to go as long as possible.

 

Thanks.

 

Unless you are in a cold climate, 10w-40.

You will get many varying opinions on this. Personally I don't like synthetic oil and just use conventional. Mobil 1 is an excellent brand though and I would also use their filters as well. No matter what though, change your oil every 3k and it'll last forever.

....."You will get many varying opinions on this."  Well said. 

 

I was told Valvoline 10W-40 and always genuine Subaru oil filters.
 

the owner manuals have a guide for oil grade, and it takes into account of your daily temperatures. I have been using 20W50 in minus 5 to 40 C last eighteen years !

Don't expect anything special about the Subaru filters, other than getting hosed on the price.  I use standard auto store filters, but you have to beware of the larger diameter filters that NAPA claims will fit.  They go on but do not have enough clearance to the back of the auxiliary fan strut that holds the fan motor.  When you hit a bump, that strut cuts through your oil filter and you have a sudden lose of oil pressure and oil.  I change oil every 2500 miles and oil filters every 5000 miles.

Were synthetic oils out in 1980-1990? when our Subaru engines were made? They weren't out when they were initially designed. So how do we know that the oils Subaru recommended in 1980 are the best oil to use now?

 

While my ea81 engine was off to the rebuilders I wrote to Penrite and they recommended while running in to use running in oil for 300 miles, then semi synthetic then optional to go full synthetic. So now I use 10W-40 full synthetic. I was advised by them to not use 15W-50 in cool climates as the oil wont lubricate sufficiently when the engine is cold.

 

The disagreements persist. But I wonder if we old fashioned folk stick to things for too long...in this case do we stick to non synthetic oils for what could now be irrelevant reasons?

 

Wiki states the advantages of synthetic are numerous to mention. Disadvantages ? 2 only- Cost and some environmental reasons....that's it!! 

 

Imagine you have a large empty drum. You fill it with golf balls. You will note the air between the golf balls. Then you fill it with ball bearings. Much less air between them. If the sides of the barrel is a piston sleeve then you can imagine how much better the lubrication is. Equals longer life, less wear.

 

Personally I think Mobil 1 synthetic oil is fine. Ask Mobil I reckon. But times change and I think we should change with them. If the OP uses full synthetic oil from now on then wear will be much less.

 

Tony

I vote synthetic. GeneralDisorder is a supporter to going full synthetic as well. Also, I do a lot of hwy and when I was running regular oil I was pushing oil changes 7k miles and the oil still wasn't completely black on its way out. I went synthetic so I could go even further between changes.

im a synthetic guy, my 220,000mile engine 3 years later seems fine with it. i change it every 5,000miles even though its suppose to be 7K so im actually being nice to my engine.

 

10w-40 Oreilly Full Synthetic High Mileage Oil with a Wix oil filter, thats what i've been using..

Synthetic all the way. Right now I'm using 10W-40 Valvoline High Mileage blended synthetic; hoping I can rejuvenate some of the seals by using HM oil becauseI have a few small leaks. Next oi lchange I'm going for Valvoline full synthetic 10W-40. For oil filters my family has used FRAM for 20+ years. I use only their high end Ultra filters

Edited August 17, 201510 yr by Sapper 157

there are varying opinions because practically speaking it doesn't matter.

 

the causation between N/A engine longevity and oil choice is extremely weak.  if everything else is perfect (no overheating, frequent oil changes, no compromised oil, good maintenance) - oil choice is nearly benign.

 

synthetic oil is great, more forgiving, use it unless you have a reason not too.

 

conventional works great too.

 

240k on my current daily driver and, as it's always been, my secret has been whatever cheap oil and filter are on sale.  I've had a high percentage of Subaru's use oil, otherwise I would use synthetic more often.

Edited August 17, 201510 yr by grossgary

So, as far as synthetic oils go, which brand do y'all think is the best? Or are they about the same?

 

Btw, thanks for all the replies, really helps.

Amsoil is the very best oil money can buy. But at 12 bucks a quart it is really spendy. I usually go with Valvoline SnyPower or Quaker State Ultimate Durability.

 

http://oil-tech.com/motoroil-comparison.php

​Here is a comparison of some of the top oil companies. If you don't want to break the bank by going with amsoil (and believe me I don't blame you if you don't!) then you can use this cart to find a good medium.  

I run conventional  10w40 in the summer and 10w30 in the winter. That is what my dad has done with his stuff for the past 20 years and never had a problem. Napa had a sale going for $2 a quart for the premium napa brand so i bought the limit 2 cases. 

I've had my Subaru for 25 years and it has 210K mi., engine runs great with good compression.  I use 10W40,  10W30, many different brands over the years along with whatever filter is on sale.  Lately, I've grown fond of 10W40 Motorcraft synthetic blend.  I get a good price at Walmart.

I own my "BumbleBeast" since new, and during all these thirty years, I've poured 20W~50 Oil on it; I used mineral until two years ago, when I started to use to Sinthetic, I use Valvoline's "Max Life" for High Mileage engines, which makes my EA82 to be Quieter, somehow.

 

I know this thread is Regarding EA81, but the EA82 is pretty similar, so my experience might add a little to the Thread; mainly because older engines has wider tolerances than new ones, and using a very "Thin" oil on these EA engines is somehow, an Overkill that might lead to premature wear.

 

At the end of this Writeup, you can see a Chart from a Subaru Manual, regarding SAE grades to be used, in relation with Climate's temperatures; also you can Download an Australian made Test that shows you the Shearing made on a Machine, using different motor oils as metal-to-metal barrier:

 

~► http://www.ultimatesubaru.org/forum/topic/126284-how-to-determine-which-is-the-best-motor-oil-for-your-car/

 

Kind Regards.

ok well, we have had many replies here which is predictable on the topic.

 

But I wonder how we gauge a "good" oil from a not so good oil. Colour of the oil I'm afraid is not a good indication of whether its good or not. Quietness might not be either as thick oil could do this....but is thick oil masking an issue like poor tolerances? I wonder. What I'm saying here is, we are not experts and saying "its been a good oil"...how do we know? Most of us will only know when our engines get to high mileage and even then it might not have been the oil that has caused the wear.

 

So I rely on experts to tell me. Here is a second letter I received from Penrite oils

 

Dear Tony, you recently contacted out technical support team of Penrite Oil Company

 

Your enquiry was-

 

Subaru ea81 freshly reconditioned you recommended me using running in oil then 20W-50 semi synthetic oil and I could go HPR-10 diesel oil as it has high zinc. Wouldn't I be better off using 20W-50 petrol oil (have done 5000 kms)

 

Reply

 

Last years recommendation (to you) was actually HPR 15 oil not 20W-50. You could not move to HPR 10 (full synthetic) SAE 10W-50.

 

There is no advantage going to 20W-** oil, this would just give you less protection on cold starts.    Cheers Alan.   end letter.

 

__________________________________________________________________________________________________________

 

 

Penrite's HPR 10 (synthetic) oil is sold as oil for diesel engines AND petrol engines. It was recommended as it has heaps of zinc in it. Zinc reduces wear substantially. Google Penrite HPR10 and read on.

 

Any synthetic oil would suffice at the right SAE and I'm not an agent for Penrite. I just like them because they reply to my emails fast for my particular engine and its condition. I live in Victoria Australia which can be very cold (snows once every 4 years) and hot (can cook eggs on the road lol)