What grade fuel do you pump?

Thanks for the info on the 06 manual. I hadn't heard that. Unfortunately it just complicates things. Maybe 87 is best only for 07+. However, this ties into the whole "engine design" issue. I'm really not familiar enough with the details to understand how the design is different for different octanes. I would suspect some of it is mechanical (which shouldn't be different for all Gen 2 Tacos). Others, as you suggest, could be ECU related (which would be easy to change between years).

 

To break it down to it's simplest terms. There was a change in how the MPG testing standards were done in 06. The engines were tested and rated on 91 octane before that. However, knowing that the majority of the population never reads their manual, and were putting 87 in their vehicles they were not "performing" as advertised.

The test was re-done with 87, and the MPG, as well as Horese Power and Torque ratings were changed to reflect their output with 87 octane.

There has been nothing changed with regard to the engine for 05 to now. It is just a change in the write up.

 

Highest grade possible. It helps my truck not make that obsessive ticking noise. Took 2 tanks and now no more tick!

 

VVT-i, a very ingenious solution to the "one camshaft can't do it all" situation. Remember back when us ole farts were messing with changing out our camshafts and adding high dome pistons and hot ignitions to get that high end power and revs? Well, it made our cars/trucks "lope" at idle and slow speeds. We put up with it because it was cool and we got the high end we wanted but for a production vehicle to sit there and lope at idle, that don't go over so well.

Toyota has figured out a way to take a camshaft and by adding a helical cut to the inside of the outer camshaft pulley and by using a special rocker plate to acuate the valves. When you stomp on the gas in our VVT-i Tacomas, a special valve inside the rocker arms opens up and allows oil pressure to advance the camshaft timing via that helical cut in the camshaft pulley and at the same time the special rocker plates enables a second camshaft lobe to operate the valves increasing lift. It's brilliant! Another reason to keep the oil VERY clean and not let sludge build up at all.

As far as gasoline octane goes perhaps that shaft works both ways to retard the timing somewhat but I would suspect it is just the timing. And it seems there are (2) different ways to measure Octane and one comes out to 87 and the other number is 91. No flames intended, your mileage may vary, pun intended!

 

So the conclusion is... use 91 for best performance and mpg.




?

 

It could be the way I drive, but everytime I put high octane in the tank my milage drops a little.

 

This was a great post on a Reg vs premium gas test on Toyota Nation by Chazmanian from a while ago.

Originally Posted by Chazmanian
Heading out for Oregon tomorrow and have decided that I'm going to chart the MPG differences between Fuel grades and actual miles per hour. its 1300 miles from Colorado Springs to Bend Oregon which will give me an oppourtunity to really see what differences there are between fuel grades and what type of mileage increases that I can get from lowering my average speed. After reading the various posts and throwing in my own twisted wanting to go too fast ideas I have determined that my 11-12 MPG overall average on the highway towing my 1500# Cargo trailer is probably a combination of, Cheap Fuel (I tend to use the 85 when out on the road) and pushing to hard and to fast ( Averaging 70-75 mph and usaully turning 3000 Rpm's) in an attempt to arrive at jobsite, complete job and get the hell back home! So i'm taking my time this trip and and doing some some research. I did break the 300 mile barrier in all town driving this past week with 91 Octane...a milestone for me as I generally get 280 per tank before the light goes on at 17.7 Gallons.

So its gonna be a tank of the good stuff at 55 MPH
A tank of the cheap stuff at 55 mph
And a tank of the cheap stuff at 75 mph
and finally a tank of good stuff at my usual 75 mph

I have already found in previous seat of the pants tests that "DaKine" 91 octane "Pulls" my trailer a helluva lot better than the 85 octane "Ditchweed"...I've just been to ignorant to actually see if I can save money overall by using the 91 octane and slowing the hell down. The 55mph will be hard to do for 5 hours but if I can get a 25-30% increase over my 11-12 mpg previous averages it may be worth it.

I always take my Laptop on the road and will only stay in La-quintas due to the excellent hard boiled egg and bagel breakfasts along with the free Wi-Fi. so i'll post my test results as soon as I arrive in Oregon monday morning and calculate.

Well I certainly had a helluva 3000 mile ride this past week...Colorado to Oregon then down to Carson city nevada then back to colorado again. 2900 miles total all with my 5x8 cargo trailer and lots of monster energy drink. Had a hard time getting consistant terrain for my testing but but did my best as the return trip from Navada to Colorado on I-80 was fairly consistant....Except for that windy ass Salt Flat where I was certain that I would be blown into an erternal salt flat hell. Very poor mileage for that 100 miles.

If you pull a trailer with a Tacoma buy the 91` octane as its benefits are incredible. I was able to hold 5th gear OD for long periods of time when fueled up with the "Good Shit". There were even long flat sections where I held 75-80MPH in 5th gear OD after my tests and it was actually "Do-Able" with the cheap gas the motor will not hold 5th gear and will actually try to downshift out of 4th. Cheap gas and trailers do not mix well, it seems as if I was abusing my truck by running the cheap stuff. Anyhow heres what I got holding true to my MPH and fuel grades. No A/C was used during my testing.

The good stuff(91 Octane) at 55mph: Right at 15.5 MPG! 17.5-17.7 Gallons or 271 Miles til the light came on. I was really shocked that I got this type of mileage, Rpm's are the enemy and with the good gas I burbled along in 5th gear happily.

The Cheap stuff (87 Octane) at 55mph: Right at 13.9 MPG or 243 Mile til the light came on. Still way better than I had done in the past but that crappy gas made me have to run in 4th gear for most of the tank even on the flat areas. my truck hated me for using this shitty gas and complained bitched and ran at high Rpm's the whole tankful.

The good stuff at 75 MPH: 12.4 MPG or 217 miles til the light came on. Major loss at 75...Major. Although I do prefer to run at 70-75 it hurts me pocket badly! This number gets worse with the A/C on touch.


The cheap stuff at 75 MPH: 11.8 MPG or 206 mile til the light came on. This was difficult as you will beat the shit out of your Tacoma trying to hold 75MPH with cheap gas, Funny that the mileage numbers are actually closer but....If my truck wasnt a lease I would have cancelled this test after about 25 miles as I was often hitting 4000 Rpm and really abusing my truck in an attempt to find my true MPG. I will never again attempt to run this truck at 75 MPH with a trailer and cheap gas. with the 91 Octane its really no problem but the cheap stuff had me downshifting to 3rd gear at 70-75 MPH which is completely insane.

 

Thats a good article, so I think I should go 91 octane.

It looks like its better in any way!!
Dont you guys think???

 

I appreciate you finding that Demoncleaner. Only issue is, I rarely haul a trailer. That's good advice if you do though. This kinda ties into that wikipedia link I posted earlier. If you need higher performance out of your engine (racing, towing, etc.) then higher octanes are worthwhile.

Me, I do mostly city driving. When I'm on the highway I do 70 mph at 2K RPMs.

 

I appreciate you sharing that info. I'm even able to follow some of it considering my limited knowledge of engines.

 

There is a point to where octane is a waste.
I use 91, and have been known to use 93, which produced no gain,
The 91 did.
Mine will burn 87. But it is not worth it.
I have a TRD Super charger and TRD Headers and a Magna Flow exhaust. TRD does not make a good exhaust for the Taco.
There are better headers out there too.

 

Hey Fellow Tacoma Truckers,

I figured I'd share my information with you all. I've pretty much trended the mileage on my truck since the day I bought it a year ago. Some things to know:

(1) I live in Colorado (elevation approximately 5200 ft)
(2) Regular Grade starts at an Octane Reading of 85
(3) My truck is a TRD Double Cab Long Bed
(4) I usually drive the truck consistently 4 days a week on the same route to work (so 8 trips total), at a speed not greater than 65 MPH
(5) There are 2 obligatory stops on the way to work, and 7 stop lights
(6) Winters here are cold and snowy so in the winter months my mileage suffers from 4x4 driving and heater use.
(7) I have been using 85 octane for the most part, just to see if there are any major variations in the gas quality. I did notice a loss of some power when I initially moved down from the premium, but I don't tow or haul anything usually. Plus, I experience no pinging or engine issues. ALSO, the dealer said it was okay to use 85, it's just not in the manual because only Colorado sells 85.

Other than that, feel free to use the data for your own conclusions. If you see a zero-N/A entry combination, that's because I had just started or forgot to write down the mileage in the previous gas fill up, and thus had to wait again to calculate a mileage. Feel free to ask questions! have fun out there riding!!

 

When spring arrives in New England, I will give the 91 Octane a try for a few tankfuls. I use strictly 87, there is no 85 grade of fuel in Mass. According to most authoritys including Toyota, they recommend 87 according to the manual and from some mechanics and from C/D and R/T when the subject comes up about grades of gas producing better mileage and more power, they don't see significant gains. However supercharged Toyota truck engines must run 92 or 93, no questions there. Haven't heard of or seen any turbo'ed Taco's but I don't doubt there are some.
Jeff, 06,V6, 6spd, 4x4, SR5

 

Jeff, we do not have less than 87 either.
I too would like to hear from someone who has turbo charged and after cooled the 1GR engine.
SC makes more sense for me.
I need the tourque in the low RPM band.

 

Mid-grade here. I throw in a little Lucas treatment every few fills.

 

Revival time

I read a while ago about gasoline octane rating and fuel mpg. The octane rating is basically a knock resistance rating. That's why higher compression motors need it. Our computers will retard the timing while using lower grade gas (resulting in lower mpg). Yes the lower grades are "purer" and have more energy per unit, BUT that also makes them more volatile and prone to pre-detonation (spark knock). From my understanding, the mpg and power increases found in higher octane gas is purely from the computer being able to advance the timing because of the fuel's greater ability to resist pre-detonation. Advancing the timing results in more complete combustion and more time for combustion to act on the piston, so less fuel is needed for the same, (or better) results. But that fuel must be able to resist said pre-detonation.

 

I know that this is a pretty old thread, but if you haven't run the numbers please take a look. It is a mistake not to use premium fuel on the 4.0 V6 trucks because they actually get a little better mileage with it and a search here will show that many with the 4.0 V6 have.

In California regular is about $4 a gallon and premium is usually 20 cents more. For the comparison, let's say you have $80 for gas.

At $4 a gallon you will get 20 gallons of regular fuel for your $80 and lets say you get 17 mpg average. That $80 will take you (20 gallons X 17mpg) 340 miles.

Now premium fuel at the same station will be $4.20 per gallon (20 cents more). That same $80 will get you say 19 gallons (or one gallon less). However with premium (besides the extra 'pep', lower risk of detonation and cleaner emissions all results from the more efficient slower burn) you are now getting 18 mpg; or 1 extra mpg. Now that $80 will get you (19 gallons X 18mpg) 342 miles. That is essentially the same amount of miles (actually 2 more, but who's counting) PLUS all the other benefits for the same price.

It DOES NOT cost you more to run premium gas in the 4.0 V6 trucks. If anything it saves you money and you get many added benefits. You only need 1-mpg more for the costs to even out. Test it on your truck to see for yourself.

Here's how... fill your tank with regular until the pump automatically shuts off. Zero your trip odometer. Run your truck normally until its close to empty. Fill you tank again at the same station until the pump automatically shuts off, but this time with premium. Record how much fuel you put in. Check your odometer. Divide the mileage by the gallons you put in (or used). You will get a mpg number. Save that number. Now zero your odometer again and do the same routine once the tank is again empty. If the mpg number from the premium is higher by 1 or more. You should use premium because it's cheaper per mile than regular and its generally better for the truck.

Finally, the higher the fuel cost, the more money you will save by going to premium. IF fuel goes to $5 a gallon and you are getting that 1 mpg more you will be saving even more money. Conversely if it goes to $3 a gallon you will need to get a better than 1 mpg gain for the costs to even out.

I hope this helps all of us to get the most from our trucks!!

 

i agree with everything you've said, however, here in florida, the difference between regular and premium is about $.29 so for us it'd have to be about 2 mpg difference to benefit. but i am going to try it on my next fill up.

 

If you run a forced induction you need 91 plain and simple. Any thing else nope.

 

Recently came back from a 2000 miles trip pulling a camper 91 one way 87 the other absolutely no difference, no difference in perceived power no difference in mileage. Saw no difference in Ultra Gauge reported timing the only thing that suffered was my credit card. Yes this was hand calculated. No way I’ll waste money on 91.