I was just filling up this morning, and was just wondering which octane rating would be ideal to use?

I was always under the impression it's always better to use the higher octane rated fuel... (better mileage, cleaner fuel system, etc..)

What's everyone out there using? 87, 89, or 91

Should I stay away from the 87, and look to use the supreme stuff?

Any comments would be helpful...

 

This topic may be found on several older threads. Without rehashing ground that has already been covered, the TCH is designed to run on 87 Octane fuel and using fuel with a higher octane rating may actually decrease your FE.

There may be some benefit to using "Upper Tier" gasoline offered by Cheveron, Shell, Union Oil and several other suppliers. These fuels were developed as a result of cooperation with several auto manufacturers, including Toyota, and have additives that may be beneficial to engine life and ICE operating efficiency.

 

FastMover is right about loosing gas mileage with the higher octane gas. I have owned other cars trying to up the mileage using gas additives or higher octane gas, only to find I loose gas mileage.

Purchasing the Top Tier gasolines is the best way to go. Best to keep your tires aired up about 35 to 40 psi cold. You can use 40 in the Energy tires and they still seem to ride good. Easy driving and using a top tier gas usually gives some nice results.

Be sure to click each of the links, especially Retailers where it list the best brands of gas to buy.

http://toptiergas.com/

 

Higher octane gas actually contains less energy. Use what the manufacturer recommends, in this case 87.

 

I have always believed in the "higher octane is better" in all my cars since 1957. (yes 50 years) But this car runs best on 87 octane over the past 12 months and 10,000 miles. Like the others say buy 'branded' fuel mainly to avoid contamination and to get the additives for summer and winter driving.

 

I would agree to use the octane the engine is designed for. I know of a exception to that. Those driving the Ford Taurus made around 2000 with the 3.0 V6 engine with automatic. It was designed for 87 octane. But it runs much better with improved gas mileage if you use 89 and some use 91 octane.

My wife bought a used 1999 Ranger pickup. I uses a similar 3.0 V6 engine and has a automatic transmission. It's always been sluggish in low gear and not much power in second. She tried a few gas additives like techron and later lucas. But when she went to 89 octane then it ran like a new engine. She also picked up little more mpg in the process.

None of that will work with the excellent designed engine like we have in the TCH.

 

Knock sensors in many (probably most) cars retard the spark allowing the use of lower octane fuel but with a performance penalty. But as long as the octane level is sufficient to eliminate knocking without retarding the spark then there is no reason for additional octane.

I've got a 2000 Ranger with the 3L V6 and manual transmission that knocks on regular in the summer months and needs midgrade. But it doesn't improve gas mileage. And although I usually use "Top Tier" gas, Chevron, I found that I get better mileage using Costco gas. Back in the late 1960s I saved money by running Gulftane (a sub-regular grade gas) in my VW with no loss in gas mileage.

Sometimes premium grades have more additives, but it would appear that in the Top Tier brands all grades get the additives. Thus the only thing you are buying with "premium" gas is increased octane which you may not need.

 

More on the wife's '99 Ranger I mentioned earlier. Hers also pings some only when going up on either of the overpasses here in town. I found on the internet thats normal for these 3.0 pickups with the FFV engines. The engines are also designed to burn ethanol. One fellow replaced all his injectors and it helped very little. Another replaced two injectors that Ford said was bad. Still he had some ping under heavy throttle.

My wife gets great gas mileage with her pickup. She bought it used and it does have the larger tires on it. Being a automatic with overdrive, she drives 45 miles per hour the 8 miles to town. She gets 26 to 28 mpg with the AC on. She runs it on low fan. She did go to the mid octane fuel and that eliminated the ping and she picked up a some gas mileage. We use 5W-20 mobil one in that one. The pickup had 18,500 on the clock when we bought it from the Ford dealer. Its now 5 years old with 30K on the meter. She don't drive it that much.

She also uses top tier gasolines, was Chevron but these last few years seems that Phillips 66 may be a little better. I have had good mpg results using Phillips in the TCH. Conoco and 76 should be the same gasoline.

 

Carbon build-up in the heads will cause your low-compression (used-to-be-good-at-87 octane) engine to knock. The higher octane gas will compensate for that, much as it does in engines that were DESIGNED as high comp engines. Eventually, you'll be looking at a valve job.

 

I doubt the wife's pickup has any deposits. She has run Techron and Lucas for over a year messing with that slight ping when she drives up the overpass. She fills at a half tank with the 87. Then the next tank she will fill with the mid octane gas. That eliminated the pinging. The results are faster cold morning starts, better acceleration. She said she picked up a little gas mileage.

Strange how increasing the octane in most engines is a waste of time.