Originally Posted By: KHP
Thanks for all the encouraging responses!
Originally Posted By: FZ1
Mobil 1 Extended Performance 5w30?
Mobil 1 Extended Performance is an excellent oil, but I don't think it's as good of a fit for my car. My WRX consumed a little of Mobil 1 Extended Performance 5w30 oil (.75-1Qt) during my 7500 mile run. I know that amount is nothing to fret about in that long of a run, but I decided to give Pennzoil Ultra a shot and there's less observable consumption (maybe .25-.5Qt) at 7500 mile intervals.
As a second note my car shredded Mobil 1 Extended Performance oil out of viscosity tolerances at the 7500 mile interval that I ran it. Pennzoil Ultra only budged a few tenths of a point out of original viscosity spec.
Originally Posted By: Ibrahim
Just because it does not meet HTO-06 spec officially does not meet that it is not capable off, Pennzoil Ultra 10W30 will be fine to use and there are alternative options as well. Besides, I have a hunch that Dexos1 spec prolly overlaps with HTO-06 somewhat. Surprisingly, thinner oils are also faring okay in Subie's, as per the recent used oil analysis I have come across.
Add my car to the list of turbo Subaru's that loves this thinner Pennzoil Ultra oil. It was nice to have access to an off the shelf oil that I know work well on my car. We'll see what happens in the next few months. Maybe Walmart will restock them, but as of right now I have 22,500 miles worth of Pennzoil Ultra 5w30 Oil changes. I'll pick up two jugs of the 10w30 Pennzoil Ultra as a summer fill after work today.
Originally Posted By: Hokiefyd
I have two comments. First, just because an oil doesn't list a certain specification, that doesn't mean that it doesn't meet the performance requirements of that specification. Honda's HTO-06 specification is for 5w30 oils only, so no 0w30 or 10w30 will list that specification, even though they may meet the performance requirements of that specification. Second, Honda thought that performance above and beyond the standard API/ILSAC requirements was important for its K23 turbocharged engine, so it developed a lubricant specification for that engine. Subaru apparently didn't feel that its turbocharged engines required anything other than standard API/ILSAC oil, so that's what they specify.
Regarding moving to a 10w30 from a 5w30 in the same oil line? It's a non-issue; you engine won't know the difference.
Thanks for the explanation regarding HTO-06 only being attached to 5w30 weights of oil. I didn't realize that Honda ever only concerned themselves to attach the spec on 5w30 grades of oils.
Originally Posted By: bluesubie
If you are going to switch to a viscosity not listed in the manual, you might as well switch to an xW-40. 5W-40 is listed in the manual, although it says "5W-40 conventional" is allowed for replenishment.
You must not have purchased your car at the beginning of the model year. The earliest 2011's allowed 40 grades and 50 grades in desert and/or other severe conditions. I suppose engine fairies made internal changes to the engine and left owners an addendum to the manual.
-Dennis
I ordered my WRX August of 2010 and got it end of October 2010. I would like to say that I got it close pretty close to the beginning of the model year roll-out. You are correct that the original manual stated 5w-40 is an acceptable fill. The addendum arrived two months later completely taking it out as a fill and acceptable only as a replenishment if 5w30 is unavailable.
A lot of people love the heavier weight 5w-40 oil as fill for their turbo Subaru's. I don't want to do much more of viscosity experimentation on my car. I've gotten a good trend data with the 30 weight oil on my car. 10w30 and 5w30 is very similar viscosity at operating temperature and considering that we hit +100 deg F during the summer time I don't think I have to worry too much about cold viscosity.
When I exhaust my Pennzoil Ultra stash then I may reconsider heavier weight oil as a replacement.
Interesting. I use Mobil 1 Extended Performance 5w20 in my 02 Accord V6 and it does seem to begin using at about 3500 miles of short trips.I begin topping up to the full mark and looks like I'm on pace to use about .75 quart in 6 months and 4500 miles. I can smell the gas in the oil so I guess I've got some fuel dilution from all my short tripping.
