[bob022004]

Hey SD....you do know that it hurts your performance and gas mileage when you use a higher/lower octane than your motor is designed for? Try using just 87 and you'll see a slight improvement. I had a friend try 110 octance gas in his SRT-4 and it ran like s***. Unless your engine is tuned for the higher octane all you're doing is wasting your money.

 

[demob05]

Hey SD....you do know that it hurts your performance and gas mileage when you use a higher/lower octane than your motor is designed for? Try using just 87 and you'll see a slight improvement. I had a friend try 110 octance gas in his SRT-4 and it ran like s***. Unless your engine is tuned for the higher octane all you're doing is wasting your money.

For those of us with the 2.5L 4 cylinder, just confirming that 87 Octane IS the recommended... the manual seems vague, saying it can take 87 Octane, but for BEST performance/results, use 91 Octane. Most manuals just tell you what Octane to use and that's it.. Is 87 the best for this engine (that's what I'm assuming)??

 

[RJHink13]

XE gas mileage

I just bought an 06 Frontier and the first tank through I only got 17.7 mpg. I drive like a mad man, so I am not sure if that had anything to do with it. I drive all highways to work about 25 miles and average about 75 mph. I went 320 miles and filled up 18 gallons. Whats wrong? It looks like everyone else is getting over 20mpg. Whats the deal?

 

[inyourface1650]

Dude, it depends. Some people due to enviormental circumstances, whatever, just dont get the mileage. I, for example, only get 15MPG on my 4.0L fronty, while some people get over 20. It just depends on that big hill right when you get on the freeway, how much you use A/C, etc, and your foot.

 

[bob022004]

Demob05-Not sure about that one. I'd say call Nissan for clarification. But unless it specifically says premium unleaded only i'm going 87 octane and saving my money because the potential gain you might see out of getting 91-93 octane isn't worth the cost.

 

[thrillhouse]

Demob05-Not sure about that one. I'd say call Nissan for clarification. But unless it specifically says premium unleaded only i'm going 87 octane and saving my money because the potential gain you might see out of getting 91-93 octane isn't worth the cost.

Lemme clarify that higher octane fuel DOES NOT give you more horsepower if thats what you mean by performance. (whoever said that) Stick with what bob said and use teh 87, if shit starts pinging or it gets really hot then move it up to 89 and if it still does it hit up teh 91.

 

[SDBryan]

Again - I noticed an improvement in gas mileage, and the pinging goes away with 91....

I usually fill up with 87, but for this trip - I wanted to see if the 91 made any difference, and it did...

Considering at 3500 rpm its fairly hot going 89 MPH... I'm assuming since 91 burns COOLER than it may combust a little better and that may be the reason for the improvement in mpg...

I'm just sharing what happened... I would like to find out why it pings with 87 however....

Would an exhaust and high flow intake help mileage or make it worse?

 

[bob022004]

it could help because it improves the airflow of the engine....if you stay out of the loud pedal. but the improvement won't be that noticable. today's newer vehicles aren't near as restricted as the emissions stuff from the 70's and 80's. Technology has allowed for less restrictive intakes and exhaust systems from the factory than before.

 

[thrillhouse]

it could help because it improves the airflow of the engine....if you stay out of the loud pedal. but the improvement won't be that noticable. today's newer vehicles aren't near as restricted as the emissions stuff from the 70's and 80's. Technology has allowed for less restrictive intakes and exhaust systems from the factory than before.

Yeah but intakes and exhaust systems have restrictions due to the fact that car manufacturers put resonators and baffles in EVERYTHING to reduce sound, usually aftermarket intakes and exhausts get rid of those restrictions making it louder, give a lil bit more power and lil bit better MPG.

 

[tmendeol]

The higher the octaine rating the less volatile the gasoline is. It takes higher temperatures to cause it to combust. So when you're getting a "ping," or detonation, from 87 octaine it's because the temperatures in the cylinder during the compression stroke are high enough to cause the gasoline to ignite before the spark plug fires (which usually also means that the compression ratio is high and timing is getting into the too advanced range for the fuel you're running). With with the timing advance causing the engine to just start pinging with 87 octaine, try running 89 and you should notice the pinging go away and have optimal performance/gas milage. If that doesn't work, try 91 octaine.

Detonation is bad for an engine, placing lots of stress on the piston, rings, connecting rod, bearings, crankshaft and more. I definitely would start running higher octaine fuel to get rid of the pinging.

-Tim

 

[eb3213]

Gas Mileage

I just finished using the first tank of gas on my
2000 4-cylinder KC XE truck. I got 345 miles and it
took 13 gals to re-fill it. This equals 26.5 mpg.
It was 87 octane regular, and mostly used for
a daily 40 mile round trip commute that is 26 miles
highway (about 65 mph) and the rest on side streets.
This is with average driving, not especially conservative
nor aggressive.

I filled up after the warning light had been on for about
5 miles, so I don't know how much more I
could have gone with what was left. Being new
to the truck, I don't want to take too much of a
chance, but I suspect there was probably another
40 miles available in reserve. I am not sure
of the real capacity of the tank. So that would mean
almost 400 miles on a full tank, not bad. Of course this was
with only slight use of the A/C. It will probably be lower
in the hot months. The PO told me he got 28-29 mpg
on long Texas highway trips. We'll see.

 

[WRXrob]

bump. I'm looking at one. a 2006 XE 4 banger Auto trans.

I'd like to hear if mileage has improved, now that your trucks have broken in a bit