[zx10r_guy]

Okay, question for all you motor-heads out there. I'm pretty okay at wrenching on most everything, but when it comes to stuff like this, I start to get lost....

My wife has a 2004 Volvo XC90 T6 SUV. According to the owner's manual, we should run nothing but 90 octane or higher. With regular 87 octane running around $3.15 a gallon out here and 90 oct. even higher, we're wondering if the 87 oct. is going to do any damage to the engine.

I remember reading something in Cycle World a while ago about octanes and pre-detonation, etc., but realistcally, do we have anything to worry about? She drives back and forth to work, we don't tow anything with the Volvo....

Thoughts? Thanks! :hello:

 

[djblacksuperman]

from what ive heard... its ok to run a lower grade.. just throw in some fuel additive every other fill up or so

 

[madnessracing]

the higher octane the better (safety reasons) but that doesnt mean you can't run a lil lower octane, i know you'll be fine.:thumbsup:

 

[zx10r_guy]

Thanks for the info gang.

 

[ninjafan2]

If I was u I keep putting the 90 octane or above. If u dont u can put a hole on top of the piston due to knocking. Have a 5000 auto bill because U decide to put 87 instead of 91 or 93.

 

[bigzx10]

let me tell you how it goes in the dealership. I get alot of high end cars that are suposed to run high octane. They come in with all sorts of driveability problems after doing that for 20k miles or so. Dont do it. It is in the owners manual for a reason. Some places if the service manager wants to be a total ass or he just got put under audit they will blow out your powertrain warranty and you will be paying that cash for a new motor. It rarley happens but if you need a motor and that dealership just went under audit i know he wont give you a motor under warranty if he finds out you put less than 90 in it.

Im sure your next question is how will he know? The predetination that it causes can be heard by the tech during a test drive and right then and there it is obvious that 90+ is not in the vehicle. There are many other ways but i wont get into that.

Also the wear and tear on the motor from that pinging is insane what it does to the inside. Eventually the motor will loose compression and the blow by will be so bad you will have to tow it in. I see it everyday and thats how i make a good living by people not reading the owners manual and blowing the motors up.

Also fuel additive on a volvo is a no no. It will cause all sorts of missfires and harm the injector seals and possibly the fuel pump. You can only use volvo brand additives. That could also void a warranty. Depends on the store. I know some people think its all the same. You would be supprised the kind of testing they do on additives to make them specific to the motor brand.

 

[TC24]

Just run mid-grade.

 

[photomike666]

Octane is a measure of the burning temprature between a controled burn and a full detonation. When you run lower grade octane than the manufacture recomends you will hear a knocking sound. This is the fuel mixture detonating and it is damaging your engine.

In Aus we only get three grades of fuel; 92, 95 and 98. The Zx10 is rated at 95 Minimum, but I usually run 98. It doesn't give better fuel econony, and only a little more power, but the bike seems smoother. That's good enough for me.

 

[TC24]

Running the lower octane can give you more power and less with higher in a many situations.

 

[bbdezs]

We are at $3.90 a gal for premium out here by San Francisco . So to me it seems like your getting a bargain :lol: I always go with what the manufacture recommends, that is the safe bet.

 

[wattgn]

In the USA the octane rating used is RM/2 which is basically RON + MON / 2.

In Australia we use RON rating which is 4 - 5 points lower than the equivalent rated petrol in the USA. USA 91 is about equal to our 95 Octane.

Grant

 

[zx10r_guy]

Thanks for all of the information gang. Bigzx10 - lots of good information in your post. Thanks for telling it like it is....ccasion1

 

[getbent]

That car is turbo, DO NOT run lower octane in a turbo car. It is programed for 90+ octane and you may very likely get predetonation (pinging) when it gets real hot out and the car starts to get heat-soaked if you run lower-octane gas.

You can get away with it in most N/A cars, as they will just retard the timing, an d turbo cars will too to an extent, but turbo's require high-octane. Its just part of the nature of owning a turbo car.

 

[zx10r_guy]

Good point on the turbo gb. I think I've convinced my wife to use the 93 octane to keep the Volvo in shape.

Thanks! :thumbsup:

 

[Larry Grogan]

Also fuel additive on a volvo is a no no. It will cause all sorts of missfires and harm the injector seals and possibly the fuel pump. You can only use volvo brand additives. That could also void a warranty. Depends on the store. I know some people think its all the same. You would be supprised the kind of testing they do on additives to make them specific to the motor brand.

:+1:

I run Chevron midgrade only in my Vulva. Never the 87.