Originally Posted By: CATERHAM
Originally Posted By: bluesubie
Originally Posted By: bananaman82
Considering the trouble I had in this situation with ALL receipts and using proper oil, I am not risking it.
What kind of warranty do you have? As I mentioned earlier, most repairs made under "goodwill" from SoA have a 12k mile/1 yr warranty and
not the remainder of the Powertrain Warranty (in regards to the same type of warranty claim).
Most of all, pay attention to the HTHS comments in this thread. This is more important than the grade on the bottle or the brand of oil. You want an HTHS of 3.5 or higher and no Resource Conserving stamp in the API donut on the back. Also look for ACEA A3/B3 or C3. Unfortunately, your selection is limited.
If you run a GF5 oil, change it every 3,000 miles and hopefully that will get you through the remainder of your warranty.
Yes a lot of talk about running a heavier oil than what the manufacturer spec's regardless of how the car is operated. There is nothing extreme in how the OP uses his car let alone track it so if anyone is a candidate for using nothing heavier than what's specified he is.
And that's knowing Subaru undoubtedly has electronic safety management systems in place to prevent engine damage should the oil get too hot and therefore too thin.
But even if the safety systems weren't in effect
there still is a safe maximum oil temp' for the spec' 5W-30 before the possibility of bearing wiping could occur but no one has referenced that. And if you don't know what it is you simply haven't done your homework before blindly recommending a heavier motor oil.
And no one has mentioned the downside of using a heavier oil; namely, reduced oil flow on start-up and during warm-up when most normal engine occurs. For example M1 ESP 5W-30 may have a 15% higher HTHSV but the price you pay is a much heavier oil on start-up. Compared to typical 5W-30 like PP it's almost 35% heavier at room temperature and over 40% heavier at 32F.
Now for those that still feel a heavier oil (3.5cP HTHSV) makes them feel better, as unnecessary as it may be, there is one 3.5cP rated oil wthout the start-up disadvantages and that's the new PP Euro LX 0W-30 (API SN).
Due to its very high viscosity index it's actually lighter than ALL 5W-30s (except Sustina) on start-up and even all other 0W-30 at typical start-up temp's.
I can tell you that Subaru uses no electronic engine management safety systems that will alert someone to a potential failure if the oil gets too hot and thin (examples have been posted on this forum before). I can also tell you that there have been failures on dealer maintained, stock cars so simply following the owner's manual recommendations for all applications does not always work.
It's always easy to spot Subaru turbo owner's in these threads. They're usually the ones that have seen failures or experienced them first hand.
Your comments about the negatives of running thicker oils do make sense, although Subaru Japan recommend a Euro 0W-30 and a 5W-40 in spirited driving conditions and not just for the track.
http://www.subaru.jp/accessory/engine_oil/engine_oil/
Not an ideal translation but I think the points taken from the Subaru Castrol 5W-40 page come across as understandable:
Quote:
The viscosity of the increase will bring, high-load, it will have a strong oil film formation force and tough durability performance in the time of high oil temperature.
Oil film formation force is strong, clean high dispersibility, the wear of the bearing is small, there is a high defoaming property, there is a high oxidation stability, low temperature sludge is small, the amount of evaporation is small...
Yes, Subaru Japan does not provide the OP's warranty but I'm just saying that our comments about running thicker oils have some support and we're not just talking out of our behinds or stating that a single viscosity is good for every application. Subaru Japan still believes in different viscosities for different applications, like Subaru of America did in the past.