So I was reading up about the Toyota FJ Cruiser. You're supposed to use Premium gas in em. It says Premium only, but after doing some research I found that Toyota announced that you can use regular if you really wanna, but the trade off is you get less horsepower and less gas mileage (dunno by how much)

So if that's the case, can the same be said for Jeeps? If you use premium, will you get more power and better gas mileage? I guess it's a tradeoff anyway with the higher price for premium and all that, but still..

so what kinda gas do you use in your JK? Is Premium better than Regular?

 

I always use regular (87), per the owner's manual recommendation. Why pay more when the owner's manual recommends the cheaper stuff?

Here's a link to a lengthy debate on the subject:
https://www.jk-forum.com/forums/jk-talk-26/anyone-using-premium-6907/

 

Look here.

https://www.jk-forum.com/forums/show...hlight=regular

 

I thought today was "bring up old thread day" but I may be wrong... it's "ask what octane gas to use day".


Well this one helped bring up an old thread.

 

I was told by my repair tech to use premium when going off road and use regular when on road. when we did this i did notice a differance and Ruby was really feeling her oats.

 

I have always put the cheap stuff in my Jk. By accident I put in the good stuff. It took me a while to figure out why it was so much for a fillup! However, My Jk loved it. I have 35's. I have not changed my gears. I drive 75 miles one way to work. Trust me when I tell you I know exactly when and where my jk is going to down shift to hold the speed up. The Jk downshifted far less on the premium which resulted in higher mpg. However. I spent way more on the Premium to make it worth it so I havn't done it again.

 

If it makes you feel any better the DBW computer after it got used to your high octane would most likely "dummy down" the performance and then when you put "cheap" stuff in it again it would be a real dog.

 

that tech is full of crap. Octane does not provide more power. Octane is used to prevent predetination on high compression engines. It does not clean the engine or provide more power. You need a new tech. he is an idiot.

http://www.offroaders.com/tech/octane.htm

 

http://en.wikipedia.org/wiki/Octane_rating
http://auto.howstuffworks.com/question90.htm

 

maybe. I consistantly get 15. On that tank it was 16.4. I've never seen it before or since. I'm back at 15. For what it's worth.