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87 Octane Gasoline to Use

I recently have purchased a 2008 Cadillac SRX V-6 and the manual calls for 87 octane fuel. Many years ago my mechanic told me to always buy Chevron fuel because it includes Techtron which for allow my engine to last many miles. The problem is that on the need of power (going up a hill) and the valves clack. I notice the Chevron fuel I purchse in Florida contains 10% Ethanol.



My question - Is there any brand of fuel I can purchase that does not contain ethanol which I understand affects fuel economy.



Thank you! Frank

Chevron indeed did used to have one of the best additive packages out there, but nowadays there’s a lot of gas that meets the “top tier” requirements. Usually there’s a list of them at www.toptiergas.com although at the moment that link doesn’t seem to work.

As for the ethanol content, I don’t know about Florida, but most states have no requirements for labeling for ethanol content that’s 10% or less, so unfortunately there probably isn’t any way to know what the ethanol content of the gas you’re buying is.

The state of Florida requires fuel pumps to be labeled with “may contain up to 10% ethanol.”

However, jerseygator, almost any brand name fuel (Shell, Checvron, BP/Texaco, etc.) will have a comparable detergent in the fuel.

If you are experiencing valve noise, I would first check the type of oil being used to make sure it matches what is called for in the owner’s manual. If that doesn’t solve your problem, I would check to see if the valves are out of adjustment.

Are you sure it is your valves you hear?

This post goes off in several different directions.

Are you saying the “valves clack” only when going up hills? Sounds more like engine knock, see if using premium gets rid of the noise.

These days, in the effort to keep pollution control equipment working, the government has set fuel standards and all fuels are good. In fact don’t be surprised if you find two different brands getting fuel from the same truck.

There are still some differences between brands, but very few cars are going to notice the difference.

Ethanol is not your problem.

You may need to move up a range in octane. I would try a tank or two of higher octane and see if that helps. If it does, you may want to take you car to the dealer and tell them what happens. If they are good they may realize that the car should not be doing that and that they need to do something. I suspect if you think about it, you may be having fewer problems when the temperature is cooler.

I agree with texases.

That “valve clack” is likely to be pinging from the use of gas with too low an octane. If the car’s manual really does call for 87 octane, and if the car is pinging on gas of that octane, then the OP has a legitimate warranty issue. A Cadillac is not a cheap car and it should operate without pinging on the octane that is specified by the manufacturer. Long-term pinging WILL damage the engine’s valves and could even lead to piston damage.

Rather than putting up with this situation, the OP needs to address the issue under the terms of his warranty or he needs to buy higher octane gas. Those are the only practical choices as I see them.