Gas Octane

[TonyD]

I bought a 2000 GMC Sierra 1500 5.3L. What octane should I put in it? Does it have more power or run better with 89?

Thanks,

Tony

[tmf6902]

I would start with the lowest octane you can, if it runs fine, and you don't get any knocking then there's no reason to buy the expensive gas. Unless you have accessories that require it like a new PCM or something.

[Rookie]

Go with the lowest you can. Most motors these days are made to run on 87. If you made mods you may need to increase to 89. I would save some coin for more toys

[Rookie]

Go with the lowest you can. Most motors these days are made to run on 87. If you made mods you may need to increase to 89. I would save some coin for more toys

[silverado4800]

The lowest octane your can run is the best, the only advantage to running higher octane without it being tuned for it is that it will burn cleaner. But just run some good injector cleaner every 3000 to 5000 miles and that will make up for it.

[vortec350]

Unless you have some tuning done I would stick with 87 octane.

[TonyD]

Thanks all!

[TonyD]

One Question? What is considered a good fuel injector cleaner? They sell some at BJ's where I buy my Mobil 1. Is that good enough?

[Rookie]

I like Justice Brothers. I have had good luck w/ it.

[superbee]

I like Sea Foam, it works really well on older tbody and carburated stuff. My new Suburban hasn't had any yet though. Just make sure to keep up on your fuel filter changes, try to do it right after the cleaner runs through within maybe 3-4 tankfulls. It will wash all of the junk from the tank into the filter.

 

Superbee

[99silveradoz71]

What is considered a good fuel injector cleaner?

I tend to use Chevron's Techron. It's available at most auto parts stores.

[robsawatsky]

The octane rating itself has nothing to do with how clean a fuel burns. Energy content, combustion temperature, and tendency to produce internal deposits are very similar between grades based upon the octane rating itself. What differs is that some fuel refiners/retailers add extra detergents to the higher octane fuels, which MAY help keep your fuel system and combustion chamber cleaner.