Blazer8282 Posted June 20, 2006 Share Posted June 20, 2006 Would like to know if it is OK to use Regular Gas in an Outback 3.0 6 cyl. engine. Even though Premium is recomended. Thank You. Quote Link to comment Share on other sites More sharing options...
SubaruGoddess Posted June 21, 2006 Share Posted June 21, 2006 If it's recommended, I would use Premium. Period. It's recommended for a reason; my guess is because that's the type of gasoline that helps it acheive its peak performance. Quote Link to comment Share on other sites More sharing options...
fnlyfnd Posted June 21, 2006 Share Posted June 21, 2006 This should be moved to new gen. If it is recommened to use premium, by all means, do it. Your car will run like crap on anything less. Quote Link to comment Share on other sites More sharing options...
FindingForester Posted June 21, 2006 Share Posted June 21, 2006 Would like to know if it is OK to use Regular Gas in an Outback 3.0 6 cyl. engine. Even though Premium is recomended. Thank You. When the tank is low, try maybe 1/2 tank of reg and see if the car pings or knocks or runs like crap under acceleration. If it doesn't, you're most likely fine. If it does, then top off the tank with the higher octane. Both regular and premium gas have the same heat of combustion--that is, the same amount of energy per gallon. Higher octane gas is more resistant to preignition. Quote Link to comment Share on other sites More sharing options...
mwerger Posted June 21, 2006 Share Posted June 21, 2006 Would like to know if it is OK to use Regular Gas in an Outback 3.0 6 cyl. engine. Even though Premium is recomended. Thank You. I test-drove a 3.0 yesterday and searched the forum last night. (See the "Outback Sedans" thread.) Quite a few long threads on risking 87 octane if you search back. I'm curious about the difference between a six cylinder's requirement for premium versus a turbo model's requirement for premium. Supposedly, you might get away with risking 87 with six cylinders but not with turbo. Quote Link to comment Share on other sites More sharing options...
OB99W Posted June 21, 2006 Share Posted June 21, 2006 Would like to know if it is OK to use Regular Gas in an Outback 3.0 6 cyl. engine. Even though Premium is recomended. "OK" is a relative term. You might get away with it, in terms of knock, if the engine management systems have enough leeway. Of course, if the ignition timing gets retarded sufficiently to compensate for the lower octane, the gas mileage may suffer enough so that the effective cost of fuel will be the same as with using premium, or even worse. In general, manufacturers don't recommend premium if regular will do, since customers obviously know that the higher grade gas will cost them more. Quote Link to comment Share on other sites More sharing options...
91LegLS Posted June 21, 2006 Share Posted June 21, 2006 Would like to know if it is OK to use Regular Gas in an Outback 3.0 6 cyl. engine. Even though Premium is recomended. Thank You. I have a friend with a Pathfinder that requires premium. He uses mid-grade which is better than regular and hasn't had any problems. I understand the Nissan 3.5 V-6 can be very finickey but it seems to be fine with mid-grade. Use super once in awhile for long trips. Quote Link to comment Share on other sites More sharing options...
otis Posted June 21, 2006 Share Posted June 21, 2006 If you look below, there's the "Similar Thread" box and the first thread is titled "6 cyliinder- do I need premium gas" in that thread there is a letter from SUBARU that says you can use regular octane gas on a REGULAR BASIS if you want. the only down side is that you won't have all the performance. So don't worry about "hurting" your car if you run regular gas. just curious- why do you want to run regular gas? Quote Link to comment Share on other sites More sharing options...
otis Posted June 21, 2006 Share Posted June 21, 2006 I have a friend with a Pathfinder that requires premium. He uses mid-grade which is better than regular and hasn't had any problems. I understand the Nissan 3.5 V-6 can be very finickey but it seems to be fine with mid-grade. Use super once in awhile for long trips. my father in law does the same thing with his toyota minivan- toyota recomends premium. he runs regular for around town, and premium when he's going on long highway trips. I asked him, "shouldn't it be the other way around?" Quote Link to comment Share on other sites More sharing options...
Setright Posted June 21, 2006 Share Posted June 21, 2006 The risk is pretty small with a normally aspirated engine. A turbo engine should never be subject to less than the handbook requirement. Quote Link to comment Share on other sites More sharing options...
nipper Posted June 21, 2006 Share Posted June 21, 2006 Would like to know if it is OK to use Regular Gas in an Outback 3.0 6 cyl. engine. Even though Premium is recomended. Thank You. this has come up alot (do a search). Basically the official line from subaru is that it is recomneded, but not required. BUT you may see a reduction in performance. nipper Quote Link to comment Share on other sites More sharing options...
Elroy Jetson Posted June 22, 2006 Share Posted June 22, 2006 The difference between turbos and normally aspirated engines is mainly the turbos force more fuel/air mix into the cylinder for a more intense explosion and better performance. The fuel/air mix is also compressed already increasing the effective compression ratio. GL10's have 7.7 to 1 compression without boost, but with boost that effective ratio increases to 9 or 10 to 1 maybe. With the high compression ratio and more intense explosion when firing means that pinging can cause more damage and is more likely to occur. My XT Turbo handbook states that 90 octane is to be used. So i guess i can either run "89 mid premium" and not be a lead foot. To be a lead foot i'll need 91 "premium" to be safe. The SVX 3.3 engine has a 10 to 1 plus ratio and must run on premium. The 3.0 will need it to if the compression ration is higher than 10 to 1. N/A engines are safer to run with slight knock than turbos, but it still adds wear to the engine. Quote Link to comment Share on other sites More sharing options...
Ranger83 Posted June 23, 2006 Share Posted June 23, 2006 I have a 3.0 and log all fuel use. I have been alternating between Regular and High Test every 2,000 miles. So far I cannot tell any difference in average mpg. I have about 11,600 miles on it right now. It runs fine on Regular. Simply put, it runs fine on 87, 89, or 91 Octane fuel so far. I even ran it on an AWD dyno with Regular - full power - with no evidence of detonation or even significant spark retarding. I'm going to do another run in two weeks or so with High Test, but predict in increase of 2-3 peak whp. I invite those who preach Premium to conduct performance tests and report their results here. Here's the SOA Pronouncement: [emphasis added] YOUR ORIGINAL MAIL: What is meant by Premium fuel being 'Recommended?' I don't understand if this means only that the performance of the engine will be better with 91+ Octane fuel, or if it means that Regular grades are to be used only in emergencies. The engine seems to run very well with any fuel I have used, both Regular and Premium. Is Premium considered to be 91 Octane? Thank you ----------------------------------------------------------- Thank you for taking the time to contact us. We hope that you have been enjoying your 2006 Outback 3.0R Wagon. The 3.0-liter H6 engine is designed to operate using unleaded gasoline with an octane rating of 91 AKI or higher. Regular unleaded gasoline with an octane rating of 87 AKI or higher may be used. This is not just for emergency situations. You can use regular unleaded fuel in your vehicle on a regular basis. However, for optimum engine performance and driveability, it is recommended that you use 91 AKI or higher grade unleaded gasoline. You may experience reduced output, poor accelerator response, and reduced fuel economy when using gasoline with an octane rating lower than 91 AKI, depending on your driving habits and conditions. If you experience any of those conditions while using a lower octane rated fuel, you may want to return to using 91 AKI octane rated fuel as soon as possible. Additionally, if your vehicle knocks heavily or persistently, or if you are driving with heavy loads such as when towing a trailer, the use of 91 AKI or higher grade unleaded gasoline is required Thank you for the opportunity to be of assistance. If you need any future assistance, please feel free to contact us again. Best wishes, John J. Mergen Subaru of America, Inc. Customer/Dealer Services Department Quote Link to comment Share on other sites More sharing options...
nipper Posted June 23, 2006 Share Posted June 23, 2006 I have a 3.0 and log all fuel use. I have been alternating between Regular and High Test every 2,000 miles. So far I cannot tell any difference in average mpg. I have about 11,600 miles on it right now. It runs fine on Regular. Simply put, it runs fine on 87, 89, or 91 Octane fuel so far. I even ran it on an AWD dyno with Regular - full power - with no evidence of detonation or even significant spark retarding. I'm going to do another run in two weeks or so with High Test, but predict in increase of 2-3 peak whp. I invite those who preach Premium to conduct performance tests and report their results here. Here's the SOA Pronouncement: [emphasis added] thats the one i was looking for nipper Quote Link to comment Share on other sites More sharing options...
Andyjo Posted June 23, 2006 Share Posted June 23, 2006 try running grain wiskey.. if that doesn't work, use 87 Quote Link to comment Share on other sites More sharing options...
nipper Posted June 23, 2006 Share Posted June 23, 2006 try running grain wiskey.. if that doesn't work, use 87 hrmm thats a waste of whisky nipper Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.