Originally Posted By: bluesubie
Originally Posted By: pilot1226
Originally Posted By: bluesubie
Pilot - Have you seen an owner’s manual or just looked at the oil cap? I’m curious if the language in the owner’s manual will be the same as other current models.
Yes the manual’s public now on the site. Basically it’s 0w20, but if you need to top off you can use other viscosity if you can’t find 0w20.
Saw a couple videos on YouTube that describe why Noack is important for DI. Yes EGR is the main issue but if the oil doesn’t evaporate you’ve got a better oil.
Thanks. Language is the same.
https://cdn.subarunet.com/stis/doc/ownerManual/MSA5M1900A_STIS.pdf
Page 446:
Quote:
NOTE
Engine oil viscosity (thickness) affects fuel economy. Oils of lower viscosity provide better fuel economy. However, in hot weather, oil of higher viscosity is required to properly lubricate the engine.
And 483:
Quote:
0W-20 synthetic oil is the required oil for optimum engine performance and protection. Conventional oil may be used if synthetic oil is unavailable.
*: If 0W-20 synthetic oil is not available, 5W-30 conventional oil may be used if replenishment is needed but should be changed to 0W-20 synthetic oil at the next oil change.
As per the other manuals, they do not clearly define what is considered "hot temps" or "thicker viscosity". Also, only 0W-20 is noted on the viscosity chart.
Even if there are conditions/applications where a 5W-30 would be a better fit, the numbers are probably small compared to paying CAFE fines or giving up CAFE credits when the entire Subaru fleet is considered. Try to get SoA to provide clarity on the hot temps and thicker viscosity and they will tell you to use 0W-20. In stock form, the 2.0 DIT's have been showing low uoa wear metals on very short intervals despite having fuel dilution of 2-5%.
If your concern is more volatility and IVD over viscosity, I really wouldn't sweat it. Although, if you intend to keep it beyond the Powertrain Warranty, I would definitely consider an extended warranty from Subaru and resist any mods (e.g. Cobb Stage I). Especially on a first year turbo. Being a beta tester for Subaru definitely affected my wallet. You should look up Dyson Analysis if you intend to get into uoa's. His guidance would be very valuable. Or just do oil changes every 3,000 miles and save money on uoa's.
On June 26, 2000 the EPA replied in a letter to Ford and Honda to a request to use SAE 5w-20, GF-3 oil for certification in fuel economy and emission testing. In the letter the EPA stated that they would grant the request but they were quite specific about the requirements that Ford and Honda must meet. In general:
1. No other oil can be recommended or suggested in the owners manual. It must specify SAE 5w-20, GF-3.
2. SAE 5w-20, GF-3 must be available from the dealer.
3. SAE 5w-20, GF-3 must be available from quick lube shops.
4. SAE 5w-20, GF-3 must be available from retail stores.
I have a copy of this letter but I cannot find a link to it on the net (where I got it from).