[S-N-L]

Hello everyone,

Two weeks ago I ordered a Cherokee limited with 6 cyl engine. I see the owners manual recommends 87 to 89 octane with preference for 89. For those of you who have the 6 cyl engine what are you using?

Thanks,

Stuart

 

[CDNTrailHawk]

Hello everyone,

Two weeks ago I ordered a Cherokee limited with 6 cyl engine. I see the owners manual recommends 87 to 89 octane with preference for 89. For those of you who have the 6 cyl engine what are you using?

Thanks,

Stuart

3 tanks of 87, one of 91 just to try, then back to 87. No determinable difference in mileage or performance. (and no - no pinging/detonation either).

 

[S-N-L]

Thanks,

Great to hear. I am hoping I will get good performance with 87!

Stuart

 

[onefunkar]

will use 89. only about 5 bucks a month more than 87.

 

[macfan]

will use 89. only about 5 bucks a month more than 87.

And can you give me one advantage you are gaining by doing that? The 87 is just fine as long as it doesn't have a large quantity of water in it or come out of old tanks. No one drives a vehicle harder than me and my 3.2L runs just fine on quality 87.

 

[dawhitesTH]

Since I went north of 1k miles, I'll start experimenting with 89 a bit to check gas mileage difference.

 

[KepeliTH]

I use 89 because the cost difference is minimal.

 

[Abndvr64]

So far I have used nothing but 89 but I was used to using 91 in the BMW so I am still ahead.

-Eric

 

[Jeepster1]

I am willing to bet that unless you are towing, off roading or rock climbing 87 is fine.
If I tow then I'll use 89 to be safe.
Octane should not affect MPG in the Cherokee's case.

 

[Black Rover]

I am using 87 octane and getting 25 MPG combined city and highway driving. See no need to use 89 unless you just like spending more money at the pump.

 

[PookiePrancer]

I am willing to bet that unless you are towing, off roading or rock climbing 87 is fine.
If I tow then I'll use 89 to be safe.
Octane should not affect MPG in the Cherokee's case.

That's what I would do.

The only way 89 is going to improve performance is if 87 is causing pinging, in which case the detonation sensor is going to signal the ECU to retard timing, decreasing engine output and performance. Outside of that, no one will see ANY difference.

Now, if the price were negligible, I would use BP 89, but only because it isn't mixed with ethanol at my local station. But the price difference isn't negligible.

Sent from my SPH-L710 using Tapatalk

 

[macfan]

I use 89 because the cost difference is minimal.

Maybe it is where you live but about 30¢ a gallon difference where I live. I would have to get a big mpg difference to justify that.

 

[S-N-L]

Thank you for the responses. It will be about 6 more weeks before we get our limited delivered but want to be prepared.

I am not a hard user and will not be towing anything for now so I will plan to start out with 87.

Stuart

 

[Hudsonhawk]

I would use 89 in 2 instances.

1) Towing - the increased load from the trailer will work the engine harder and could cause pinging.
2) High Temps - Where I live the summer months average in the high 90s. and several weeks of 100+ temps are normal. The heat could also cause pinging.

In both of these cases 89 is worth the cost to maintain the performance and prevent damage to the engine. With the cool weather of the winter months 89 is not really necessary.

 

[Zig]

I would use 89 in 2 instances.

1) Towing - the increased load from the trailer will work the engine harder and could cause pinging.
2) High Temps - Where I live the summer months average in the high 90s. and several weeks of 100+ temps are normal. The heat could also cause pinging.

In both of these cases 89 is worth the cost to maintain the performance and prevent damage to the engine. With the cool weather of the winter months 89 is not really necessary.

That's my approach as well. Since we seem to be hovering around the teens/low twenties in daytime temps, I am really not concerned about pinging at all...

 

[KepeliTH]

Maybe it is where you live but about 30¢ a gallon difference where I live. I would have to get a big mpg difference to justify that.

It's a 20¢ difference here but will cost me about $145 more a year at my current rate but eventually less than that once I start driving the Nissan back and forth to work.

 

[beergeek]

85 octane here in Denver, CO. Because of the elevation, our normal octane is 85. If you go to Costco for gas, which I do, you can choose between 85 or 91 here in CO. I always used 85 octane in my last SUV with a 4.2L I6 and had no issues.

 

[macfan]

85 octane here in Denver, CO. Because of the elevation, our normal octane is 85. If you go to Costco for gas, which I do, you can choose between 85 or 91 here in CO. I always used 85 octane in my last SUV with a 4.2L I6 and had no issues.

I think you have hit upon exactly why Chrysler put the 87-89 in the owner's guide. It isn't that one octane level is necessarily better than another so much as where you live. 85 or 91 isn't even offered in Michigan unless you go to one of the few remaining Sunoco stations that allows you to custom blend. I have one Sunoco station near me that offers "racing fuel" which is basically jet fuel. Maybe I should try a tank of that just for giggles and to put this thread to bed. I think you have to have "papers" to buy that though to keep the EPA guys happy. I used to run the 84 economy grade Sunoco all the time in my Monte Carlo SS without any problems.

 

[Jeepster1]

That's what I would do.

The only way 89 is going to improve performance is if 87 is causing pinging, in which case the detonation sensor is going to signal the ECU to retard timing, decreasing engine output and performance. Outside of that, no one will see ANY difference.

Now, if the price were negligible, I would use BP 89, but only because it isn't mixed with ethanol at my local station. But the price difference isn't negligible.

Sent from my SPH-L710 using Tapatalk

I had been using 87 non ethanol in my V8 GC @+.10 a gallon and picking up 1.5 to 2 MPG. So as soon as I figure out if it does the same in the V6 Cherokee I'll be set to go on my fuel.

 

[Zig]

I had been using 87 non ethanol in my V8 GC @+.10 a gallon and picking up 1.5 to 2 MPG. So as soon as I figure out if it does the same in the V6 Cherokee I'll be set to go on my fuel.

Non-ethanol gas has always given me a 2 MPG boost or better in every vehicle I have tried it on. I really wish they sold it in my state, but the @#$% politicians outlawed it. So much for common sense.