I'm trying to save money when and where I can. At my local Sheetz, they have the regular 88 octane gas, which is like 22¢ per gallon cheaper than the 87. I noticed the pump says only for use in 2001 or newer model years, but I've also seen things online that say it can only be used in vehicles that were actually built in 2001 or later. My suburban says it was built in December of 2000, and I don't want to just buy a tank of gas that could possibly damage the engine.

So the question is, can a 12/00 suburban use the regular 88 gas or should I stick to the 87?

2001 Suburban LT, 5.3 vortec, 192,937 miles

 

Are you sure you are not looking at E85 fuel, which is usually a lot cheaper than regular unleaded? The E85 is 85% ethanol, versus the 10% max ethanol allowed in the regular unleaded. Only vehicles made since 2001 that are also marked "Flex Fuel" can burn E85 without causing engine problems (and damage to fuel components).

If the gasoline is not E85, and is regular with 10% or less Ethanol content, it will not hurt your engine to burn it. You can use premium or mid grade higher octane fuel in a vehicle that only requires 87 octane, without harm. It will give no benefit to use premium, but won't hurt either. The opposite is not true however - if a Vehicle REQUIRES 91-92 octane fuel, and you fill it with 87, there will usually be performance issues (knocking, pinging, etc).

 

Sheetz gas pumps

Correct. Flex fuel is up to 85% ethanol, which is not what I'm looking for. The blue pump is regular 88, which says it is maximum of 15% ethanol. It says on the pump that only 2001 and newer can use it. Internet says manufactured in or after 2001. My suburban was built in December 2000 but is a 2001 model year. I just want some input as to whether or not it is safe to use in mine. I don't think another 5% ethanol would make a huge difference in performance or longevity, but I'm checking to make sure.

 

Ok. That is the fuel that is commonly known as E15.

Everything I find online says it is really only safe for vehicles built *since* 2001. Here is one article:

https://www.motorbiscuit.com/e15-gas-safe-use-in-car/

The big takeaway I have from that article is the statement:

And looking at the 2001 Suburban owners manual online, it makes NO mention of ethanol containing fuel at all, or E15 fuel. I looked at the 2002 Suburban owners manual, and the same section (6-3) talks about E85 (85% ethanol) in certain models, but also does not go into ethanol beyond that.

Personally, I think I would stick to the regular unleaded that is 10% ethanol or less. It's not the OCTANE that is an issue. 88 would be just fine. It's the ethanol that will damage fuel lines and other fuel system components. And it combusts slightly differently. It also leads to lower fuel economy compared to pure gasoline.

Something to be aware of is that you get less miles-per-gallon on ethanol than on gasoline. So the higher the ethanol content, the more often you have to fill up your tank. I doubt that the extra 5% content would be a huge difference, but you don't want to mess up fuel systems in a 23 year old vehicle at this point, so I wouldn't risk it.

 

See, I was reading something similar. What I read is that vehicles made in or after 2001 can use it, but not the model year. The part that confused me was that the pump says 2001 model year or newer. I did see in the article that if I filled up one time, it probably wouldn't have any negative effects, but continued use may cause problems.

My car is a 2003 Oldsmobile Alero, which is of course after 01, so it should be okay in that.

Thanks for the advice and the info. I'll just keep using the regular gas and not bother with the 88 in the Suburban.