Bluestone Posted May 29, 2007 Share Posted May 29, 2007 I've always used full synthetic motor oil in my 2000 Legacy GT since the 3000 mile mark, changing it every 5000 miles. Been using Valvoline 5/40 synthetic for a while now. No problems but I'd like to go for Mobil 1 - 0/40. Whaddya think? Quote Link to comment Share on other sites More sharing options...
Petersubaru Posted May 29, 2007 Share Posted May 29, 2007 I've always used full synthetic motor oil in my 2000 Legacy GT since the 3000 mile mark, changing it every 5000 miles.Been using Valvoline 5/40 synthetic for a while now. No problems but I'd like to go for Mobil 1 - 0/40. Whaddya think? ...It would probably would not hurt to use the 0/40, but the mobile 1 web site recommends 5/30 for your car...anything more would be over kill...0/40 has its applications, but not for the subaru..as above,.. "over kill" Quote Link to comment Share on other sites More sharing options...
Manarius Posted May 29, 2007 Share Posted May 29, 2007 0w at cold? Any protection there? I'm not seeing it. Quote Link to comment Share on other sites More sharing options...
OB99W Posted May 29, 2007 Share Posted May 29, 2007 I've always used full synthetic motor oil in my 2000 Legacy GT since the 3000 mile mark, changing it every 5000 miles.Been using Valvoline 5/40 synthetic for a while now. No problems but I'd like to go for Mobil 1 - 0/40. Whaddya think? I Know that there have been some strange climate shifts recently, but just how cold does it get in the Bay Area of California? 0w at cold? Any protection there? I'm not seeing it.A significant portion of engine wear occurs on cold start before the oil gets a chance to circulate. Low viscosity at cold temperatures can actually help in that case. "0W" viscosity doesn't differ significantly from 5W at moderate "cold" temps, but its pour point is quite a bit lower. Therefore, its main advantage is in places that get really cold, which brings us back to the question I asked above. See http://www.carbibles.com/viscosity.html Quote Link to comment Share on other sites More sharing options...
Petersubaru Posted May 29, 2007 Share Posted May 29, 2007 I am not promoting mobile products, but the capabilities of this oil (0/40) provide more shearing abilities then the 20/50...there is a catch though...not made for stronger valve springs on some cars...designed more for the low emmission cars...the only oil porsche recommends for there new cars (the newer cars have weaker valve springs then of the cars of yester year.... 0w at cold? Any protection there? I'm not seeing it. Quote Link to comment Share on other sites More sharing options...
Bluestone Posted May 30, 2007 Author Share Posted May 30, 2007 Oops! Sorry. Quote Link to comment Share on other sites More sharing options...
Bluestone Posted May 30, 2007 Author Share Posted May 30, 2007 Ok, let me more specific; I haven't seen Valvoline 5/40, lately, in some of the stores that I frequent, for some reason. They're now carrying Valvoline's 5/20, and their 5/30 and 5/50 but no 5/40.(I'm talking about full synthetic, of course) But Mobil 1's 0/40 is on the shelves( yet summer's coming up, with hot weather driving), so I'm just just thinking...."hmmm, I wonder if I could try some of that? People have said Mobil 1 synthetic is pretty good." At any rate, I'm open to suggestions; in synthetics, 5/30?, 5/50?....keeping in mind hot weather before long. I'm not wedded to any one particular brand, just want a good, well- protecting oil. I want something that's easily available, don't want to go on any hunting expeditions. Red Line's primo, I know, but it's just too expensive. So I'm choosing from the brands that are readily at hand: Valvoline, Mobil 1, Castrol(????). These synthetics are going for around $6.19 and higher around here. And is there any problem with synthetic 5/50 all year 'round, from freezing weather( doesn't get that cold in the Bay Area but it does up in the mountains, in winter) to 100+ F? Quote Link to comment Share on other sites More sharing options...
OB99W Posted May 30, 2007 Share Posted May 30, 2007 Ok, let me more specific;[...]Red Line's primo, I know, but it's just too expensive. So I'm choosing from the brands that are readily at hand: Valvoline, Mobil 1, Castrol(????).[...] And is there any problem with synthetic 5/50 all year 'round, from freezing weather( doesn't get that cold in the Bay Area but it does up in the mountains, in winter) to 100+ F? OK, let me be clearer. There's nothing specifically wrong with 0W/40, just that its better pour point may not be merited at the temps your engine is likely to see (there's a difference between "freezing" and -45 F ). Most of the major brands make a decent product that should go 5,000 miles between changes (a very reasonable interval for synthetic run in an engine that's in good condition/tune) without problem, so I'm not going to offer my opinion in that respect. As to 5W/50, you might see a slight loss in fuel mileage due to the heavier viscosity. Quote Link to comment Share on other sites More sharing options...
idosubaru Posted May 30, 2007 Share Posted May 30, 2007 i would stick with what you have been using. there is no benefi to switching. i prefer to keep using the same stuff so the seals and gaskets are always seeing the same additives as much as possible. don't know if that's true or not, that's just what i do. subaru's are far more prone to leakage than they are any engine wear problems, so i think in those terms rather than engine "life" or "wear". a well maintained subaru..never abused, overheated, etc.. run on conventional oil with 250,000 miles will still have all the cylinder cross hatching visible and the bearings will be in excellent condition as well. once you've pulled a few apart like that you realize these engines don't live or die based on oil choices. but they'll certainly leak easily enough! there's no benefit to playing with the oil. if you plan on owning the car for 500,000 - 1,000,000 miles then maybe it would make a difference, i haven't had any experience with engines in that category. Quote Link to comment Share on other sites More sharing options...
uniberp Posted May 30, 2007 Share Posted May 30, 2007 i would stick with what you have been using. there is no benefi to switching. i prefer to keep using the same stuff so the seals and gaskets are always seeing the same additives as much as possible. don't know if that's true or not, that's just what i do. subaru's are far more prone to leakage than they are any engine wear problems, so i think in those terms rather than engine "life" or "wear". a well maintained subaru..never abused, overheated, etc.. run on conventional oil with 250,000 miles will still have all the cylinder cross hatching visible and the bearings will be in excellent condition as well. once you've pulled a few apart like that you realize these engines don't live or die based on oil choices. but they'll certainly leak easily enough! there's no benefit to playing with the oil. if you plan on owning the car for 500,000 - 1,000,000 miles then maybe it would make a difference, i haven't had any experience with engines in that category. Bingo. The best oil is fresh oil. Quote Link to comment Share on other sites More sharing options...
porcupine73 Posted May 30, 2007 Share Posted May 30, 2007 Cool, is this a new oil? It's hard to tell on some of the high viscosity spread oils is whether they contain a lot of VII's (viscosity index improvers). These can shear back over time. Synthetics generally have good VI's to begin with and don't need a lot of VII's. Someone said this 0W-40 provides more shearing abilities then the 20/50. I didn't see a 20W50 on Mobil's Web site, but other brand 20W50 oils have much higher HTHS (high temp/high shear) scores than the 0W-40. Quote Link to comment Share on other sites More sharing options...
jib Posted June 5, 2007 Share Posted June 5, 2007 I am not promoting mobile products, but the capabilities of this oil (0/40) provide more shearing abilities then the 20/50...there is a catch though...not made for stronger valve springs on some cars...designed more for the low emmission cars...the only oil porsche recommends for there new cars (the newer cars have weaker valve springs then of the cars of yester year.... The subie has roller rockers, so the shear issue goes away. The big issue with older flat tappet, non-roller rocker cars is the new API spec has far less zinc allowed, as it is detrimental the the cats. Older cars need more zinc for the non-roller rockers. Jack Quote Link to comment Share on other sites More sharing options...
porcupine73 Posted June 5, 2007 Share Posted June 5, 2007 Yah some automakers are worried about phosphorous spoiling the cats before the emissions warranty runs out. That might happen if the engine starts burning through oil. So the API specs have been limiting phosphorous. Zinc is consequently limited if the blender is getting the phosphorous from ZDDP: reduce phosphorous means reduce ZDDP, which has zinc too. There are aftermarket additives such as slob (street legal oil boost) that are nearly entirely ZDDP. Quote Link to comment Share on other sites More sharing options...
jib Posted June 5, 2007 Share Posted June 5, 2007 Oops, yes, I tend to think of it as Zinc, but it's both Zinc and Phosphorous. I have two old Triumph cars (1960 TR3 & 1980 TR8) where this is an issue. No more Mobil 1 since last year. It's Redline synthetic or Diesel oil for these cars now. Mobil 1 (and other lowered ZDDP oils) are wiping cams and lifters in my buddies vintage Triumph race cars. Jack Quote Link to comment Share on other sites More sharing options...
beataru Posted June 5, 2007 Share Posted June 5, 2007 Umm... I use 0w-40 in my blueroo... Havnt had any problems yet!!! and its FREE FOR MEEE!!! so thats why I use it!!! free oil is good oil!!! especially when you can change it as often as you want! Quote Link to comment Share on other sites More sharing options...
porcupine73 Posted June 5, 2007 Share Posted June 5, 2007 Cool send some of that free oil up this way! Yes older engines that liked an oil with more ZDDP don't often like the new API spec pcmo oils. Not sure if the HDD oils are limiting anything yet something about plugging up the particulate filters or something. SX-UP is(was?) a great additive specifically made for boosting newer oils for use in older engines. It is/was made by specialtyformulations.com but they were moving since Nov '06 and I don't think they've resumed shipping yet....too bad their air tool oil is awesome. In addition to slob I think vsot (valvoline synthetic oil treatment) has a lot of ZDDP too. Quote Link to comment Share on other sites More sharing options...
ron917 Posted June 6, 2007 Share Posted June 6, 2007 Isn't STP and similar products mostly ZDDP in a heavy oil? Quote Link to comment Share on other sites More sharing options...
Petersubaru Posted June 6, 2007 Share Posted June 6, 2007 Isn't STP and similar products mostly ZDDP in a heavy oil? For STP products the "Blue" bottle has some zinc and phos in it along with a thickening agent...the "Red" bottle has more of the two chemicals without the thickening agent.. Quote Link to comment Share on other sites More sharing options...
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