Octane Question

[Mtn.Rush]

What is the suggestion for the 4.7 V8? I know the good book says 87 or higher, but what is the general concensious here? I dont want to put in 87 b/c I dont want that engine ping. I put in 89 yesterday and it seems fine. My last truck was a 4.4 V8 and needed premium. Thanks in advance.

 

[UPS92008]

87 is what Ill put in my 03 V8.

You really only need higher octane with higher compression or advanced ignition. If you mess with the cam, heads, or intake, ya might need better gas to run correctly.

 

[Specialized]

I've used 87 since '04. Seems to run smooth.

 

[p nut]

My friend uses 85 in his 4.7L and it

 

[riverider]

The only time you move up from the 87 to 89, is if you are having heavy pinging under a heavy load. if your engine is running well with 87 moving up to 89 is just wasting your money.:bash:

 

[SubSonic]

What is the suggestion for the 4.7 V8? I know the good book says 87 or higher, but what is the general concensious here? I dont want to put in 87 b/c I dont want that engine ping. I put in 89 yesterday and it seems fine. My last truck was a 4.4 V8 and needed premium. Thanks in advance.

IIRC, when they first started offering the 4.7 in the 4Runners a few years ago, they required premium. But they've dropped that requirement, it was one of the first things I researched when I started looking at the V8 4Runner lat month. (Bought mine the Sat before Christmas, took delivery 12/26)

I just put my first tank in my new 4Runner (ran out the "free" full tank from the dealer delivery) and tanked up with regular...run about

 

[p nut]

Re: Re: Octane Question

IIRC, when they first started offering the 4.7 in the 4Runners a few years ago, they required premium. But they've dropped that requirement, it was one of the first things I researched when I started looking at the V8 4Runner lat month. (Bought mine the Sat before Christmas, took delivery 12/26)

I just put my first tank in my new 4Runner (ran out the "free" full tank from the dealer delivery) and tanked up with regular...run about

 

[SubSonic]

Re: Re: Re: Octane Question

Regarding the Lucas treatment, I don't buy into that, either.

Hmm. Must have never pulled many engines apart. Carbon buildup happens, period, whether you burn premium all the time or not. Using an additive is a good way to aid in dissolving carbon when you only run 2-3 tanks of premium through a vehicle a year. Let's face it, if it weren't for carbon buildup, we'd likely get several hundred thousand miles out of every set of generic non-platinum spark plugs. You just have to make sure anything you add to your gas doesn't contain much if any chlorine - other than that, they'er fine.

Like I said, using Lucas (or a brand of your choosing) and adding in some premium (with its higher detergent content) works great for keeping the buildup to a minimum. I've seen it first hand in several street-car V8 teardown/rebuilds I've done over the past decade.

I know the carbon is a problem when I tear town my race car's V8 every other month during racing season...of course, the sanctioning body that I race under doesn't allow fuel additives or it wouldn't be as bad.

To the OP, believe what you want, but there's nothing wrong with fuel additives - and higher grades of gasoline do contain more cleaning agents (detergent).

 

[EH007]

You never have to worry about pinging because your 4Runner has knock sensors that will adjust the timing if knock (AKA ping) occurs. The sensors will make this adjustment long before you could ever hear any ping. Yes, they are that good and that quick.

But chances are that your engine will not ping even using 87 octane fuel, especially under normal driving conditions.

 

[eskimochaos]

Even though I run 93 all the time, my mom has been using 87 in her 04 Land Cruiser and it has been just fine.

The V8 does not have an EGR system which further cuts down carbon build-up but takes a small hit on MPG due to this.

 

[riverider]

We have a few stations that sell 100% real gas. Most stations sell gas with 15%+ Ethanol. I hate Ethanol and have had many problems using it.

No matter what I use in my fuel injector engines, I use Techron injector cleaner every third tank I use.:

 

[p nut]

Re: Re: Re: Re: Octane Question

Hmm. Must have never pulled many engines apart. Carbon buildup happens, period, whether you burn premium all the time or not. Using an additive is a good way to aid in dissolving carbon when you only run 2-3 tanks of premium through a vehicle a year. Let's face it, if it weren't for carbon buildup, we'd likely get several hundred thousand miles out of every set of generic non-platinum spark plugs. You just have to make sure anything you add to your gas doesn't contain much if any chlorine - other than that, they'er fine.

Like I said, using Lucas (or a brand of your choosing) and adding in some premium (with its higher detergent content) works great for keeping the buildup to a minimum. I've seen it first hand in several street-car V8 teardown/rebuilds I've done over the past decade.

I know the carbon is a problem when I tear town my race car's V8 every other month during racing season...of course, the sanctioning body that I race under doesn't allow fuel additives or it wouldn't be as bad.

One of the main factors of carbon build up is oil consumption. Your race cars burn oil. A lot of it. This is why you see more build up in your race engines than a regular street engine. Even on street engines, carbon build ups can happen, and some engines are more prone to it than others (E39 M5

 

[Nuke]

You'll gain NO performance by running a higher octane fuel than what is recommended in the owners manual unless you retune the engine for it. Don't waste your $$.

 

[MikesToy]

I pour 91 on mine. I can't tell the diff b/c i never put anything lower than 91. But my tailpipe is always clean tho. No black residue, no nothing. Here in Colorado Springs, 91 octane costs $1.65 and 87 octane is $1.53. A twelve cents difference. 12 cents multiply by 24 gallons = $2.88. I fill-up every two weeks, that sums $5.76 a month. So $5.76 times 12 months =$69.12.
So i waste $69.12 a year just for pouring 91 octane but i'm happy b/c i see my tailpipe so clean. I've seen other rigs right next to me and their tailpipes are corroded with black residue. I don't know if it's the gas causes it or not. --Me

 

[riverider]

I pour 91 on mine. I can't tell the diff b/c i never put anything lower than 91. But my tailpipe is always clean tho. No black residue, no nothing. Here in Colorado Springs, 91 octane costs $1.65 and 87 octane is $1.53. A twelve cents difference. 12 cents multiply by 24 gallons = $2.88. I fill-up every two weeks, that sums $5.76 a month. So $5.76 times 12 months =$69.12.
So i waste $69.12 a year just for pouring 91 octane but i'm happy b/c i see my tailpipe so clean. I've seen other rigs right next to me and their tailpipes are corroded with black residue. I don't know if it's the gas causes it or not. --Me

Are implying the combustion temperature is higher with 91 then 87? Is there ethanol in your gas where you buy it? If so this has a lot of effect on how clean your combustion is.
IMHO looking at a tail pipe really can't tell you anything about how octane has effected it's color or if it's clean or not clean. Just to many other things take effect.

 

[T4RSpectreSix]

I pour 91 on mine. I can't tell the diff b/c i never put anything lower than 91. But my tailpipe is always clean tho. No black residue, no nothing. Here in Colorado Springs, 91 octane costs $1.65 and 87 octane is $1.53. A twelve cents difference. 12 cents multiply by 24 gallons = $2.88. I fill-up every two weeks, that sums $5.76 a month. So $5.76 times 12 months =$69.12.
So i waste $69.12 a year just for pouring 91 octane but i'm happy b/c i see my tailpipe so clean. I've seen other rigs right next to me and their tailpipes are corroded with black residue. I don't know if it's the gas causes it or not. --Me

Incredible! I can't even get 87 here for much if anything under 2.00! (Sorry, just can't believe how prices are so different!)

 

[MikesToy]

Is there ethanol in your gas where you buy it? If so this has a lot of effect on how clean your combustion is.

Yes. 10%

 

[riverider]

ETHANOL BAD STUFF

Yes. 10%

We have found out what is posted as the % of Ethanol is many time much lower then what it is really. When you start seeing changes in your mileage and how your 4Runner is preforming, I would question the amount of ethanol is really in your tank.

 

[Benjamin Choi]

Re: Re: Octane Question

IIRC, when they first started offering the 4.7 in the 4Runners a few years ago, they required premium. But they've dropped that requirement, it was one of the first things I researched when I started looking at the V8 4Runner lat month. (Bought mine the Sat before Christmas, took delivery 12/26)

Wrong.

Who cares if someone hasn't pulled engines apart and you have? You can't even get your basic Toyota engine history right.

 

[Annoyed]

We aren't going to have a choice in what is in our gas. Thanks to the environmental lobbies, and the farm lobbies as well, more and more ethanol will be used in our gas.

You have to understand that many of the people backing these changes would rather we didn't drive anyway, let alone drive SUV's, so they don't give a hoot if it harms performance, or even the engines themselves.