The book says 87 but recommends 91 ? Anyone got any pros or cons. What about 93 ? We have a Citgo here that has 93 100% gasoline otherwise most places are 91 100% gas or 93 10% E. Thanks for the help

 

My book says Premium that's 91 or better. The consensus on all the Volvo forums i read are always use the highest Octane you have available in you area .For me that 93 and i only use that.The higher the Octane the cleaner the burn the better the engine runs and less crap is left behind. Its like Oil I use Synthetic oil only and i use the best i have available and that is in my option is Castrol Edge with Titanium cost a little more but the car runs great. I also change my oil every 3500-4k miles never more than that. Volvo says 7500 to me thats just asking for problems. GL and use 93 in the tank the car and you as the drive will be happier for it. The cars will adjust to the higher octane over the course of a few drive cycles and you may even see some added MPG. GL
Here is a thread on this same subject http://forums.swedespeed.com/showthread.php?165538-Gas

 

Using the highest octane is the best option, but you have to weigh out the consequences and decide what is best for your driving, how far away the station is, cost and mpg. I would use 93 and 91 on occasion.

 

I'll check it out. Of course it came with a full tank from the dealer so my guess is they got the cheapest.

 

Pumping in an octane higher than what the manufacturer recommends is not always a good choice. Octane rating is simply a measure of the anti-knock properties. While it's true a higher octane will not hurt an engine, it will also not help. My advice is as long as you have no issue with pre-ignition, or "ping" go by what the manufacturer recommends, any higher and you are probably just wasting money.

 

My old hippie friends thought that the higher number meant better not matter what. I do agree with you that it might not add anything. Just wasting money. I only ask because my Subaru says Premium Fuel only, where as the Volvo says 87 minimum, 91 recommened. It is kind of like that on my oil with my Suabru. It says synthetic oil recommened but not required. The gas I have no choice with.

 

Actually, a higher octane can help your engine. If you are running the recommended one (91) and your engine after some amount of miles starts to knock, switching to an even higher octane gas may eliminate that knock. Granted it may need some other repair, but, a higher octane is just a safety measure.

 

These guys are right...octane only makes the ignition slower and more predictable. We run 89 (mid-grade) in my wife's 2008 S60. She does not have a heavy foot so the car rarely sees 3000 RPM. We have no problem with pre-ignition and the car will get 32 mpg at 65 mph.