What octane should I use?

I have a 4.0 v6, what octane should I be using? From what I'm seeing in the owner's manual it says any... correct or not?

 

Correct.. use what works best for you not only the the wallet but for your driving needs.

Regular for me proved to knock to much and I went with mid-grade for daily driving. Get the occassional knock on those really really hot days but it's rare.

I put premium in when I'm pulling my travel trailer (5000#) to get the best performance possible from the engine and reduce the knock completely. Manual recomends premium for best performance as well. Numerous threads out here with explainations for everything.

 

I got customer who works for ARCO and they would only put lowest grade for city street driving but will go mid grade or premium for a long trip.

Tacos require only 89 octane.

 

i have found that there is nothing wrong with 87, although i got a little spark knock with it, but mid-grade and premium yeild a little better performance, and i cant really tell the 2 apart, so i run mid grade all the time now. mileage is good with the mid or premium too.

 

When I first bought my truck I used 87 octane, about a couple months ago my mechanic recommended 90 octane (only two available) so I switched. I notice the engine runs smoother and quieter, also you hardly hear that annoying ticking sound the engine makes. I'm sure I read somewhere Toyota recommended 91 octane for the Tacoma.

 

gotta agree......they are alot smoother running with higher octane!

 

Awesome. Yeah, I hear that light knocking sound when I'm going about 20 mph and my passenger window is down. I hear it bouncing off random objects and projecting back into the cab.

The whole reason for me to ask this question originally was that I'm only getting about 14 miles per gallon at the moment. I was at class this evening and was talking with one of my classmates. He had said that since I only have about 750 miles on my truck, the engine has alot of braking in to be done, but then after that, my gas mileage will go up 3-4 miles per gallon. This sounds legit, but is there any truth in it?

 

yeah, definitely. as the engine breaks in......you mileage will increase, enough that you can see a good improvement.

 

I've run 87 since day 1 - never noticed any problems. If gas wasn't so damn expensive, I'd treat 'er to higher octane. But - I drive to/from work and around town mostly and that's it. Not worth spending $$ for the good stuff.

 

Drove from Toronto to Ft Lauderdale & back.... Started with 87 for half the trip down. 2 adults, and enough load to make the springs sag 2".
Truck ran great. Switched to mid-grade, and I thought I noticed a small difference in smoothness. Fuel economy about the same.
Half-way back I switched to regular.
Here I noticed the engine was noisier - and you had to really put your foot into it to downshift (auto). Didn't seem to have as much power on the hills. 5 hours of driving later I switched back to mid grade ... noticeable improvement in hills and more 'willing' to go.
I know this is subjective. For daily driving I doubt I'd ever notice. There was definitely a difference for the positive, running 89 over 87 on highway use.
The difference was quite noticeable when going from mid to regular. Once you've driven days on 89, then switch - it was very apparent.
I'll stick to 87 I think (cheaper) for regular driving @ home

 

i use 87 as 89 is 10 cents more a gallon, but if i see 1 mpg inc. then it would actually cost the exact same... hmmm, will try 89 at next fillup... and premium 93 is way to damn expensive to try

 

89 here...............like others when you run 87 you get more engine noise and the engine seems to run a little rough.........w/89 I don't get the knocking and get the smoother ride. I don't think my truck has ever had 92 in it............It all boils down to driving conditions and your personal mindset...........

Oh................and god forbid that any of you let your low fuel light pop on thinking its hard on the truck some how .............. ...............

 

Why would you doubt your owners manual?

 

unless your engines poping, or premature detonation i wouldnt use a higher octaine

 

Use whatever won the hundreds of polls on this forum that you can easily find via a search, like this one: http://www.tacomaworld.com/forum/2nd-gen-tacomas/43253-what-octane-do-you-use-your-4-0l-v6.html

I will add my $.02 (maybe not even that much since I'm poor these days): I have been using 87 lately and I'm getting a lot of "dieseling" at lower rpm's. This does not happen when I use 93.

 

I just realized this thread was a month old. Let's euthanize it.