Should the older GL8 use 92 or 95 octane gasoline?

[SanIsaac]

The older Buick GL8 2.5L model, as per the manufacturer's guidance, should use 92 octane or higher quality unleaded gasoline. The Buick GL8 2.0L model, according to the manufacturer's guidance, should use 95 octane or higher quality unleaded gasoline. The gasoline must comply with the standards of GB18352.5-2013 and GB17930-2013. Below is an introduction to 92 and 95 octane gasoline: 92 octane gasoline: 92 octane gasoline contains 92% isooctane and 8% n-heptane. 95 octane gasoline: 95 octane gasoline contains 95% isooctane and 5% n-heptane. When the pistons move inside the engine cylinders, gasoline and air mix and compress within the cylinders. If the pressure is too high, knocking can occur.

[DeBrantley]

I've been driving an older GL8 for over a decade, always using 92-octane gasoline, and it's been perfectly adequate. The engine's compression ratio isn't high, unlike newer models that require higher-octane fuel to prevent knocking. 95-octane is a bit more expensive, and the money saved can be used for maintaining other parts. The manual clearly recommends 92-octane or lower—if you can't find the manual, just check the label on the fuel filler cap. Don't worry about 95-octane damaging the car, but using it long-term is purely wasteful with no extra benefits. Fuel consumption is stable too; even on long trips, 92-octane runs smoothly. Older cars are all about practicality—don't get tricked into spending more. There's almost no safety risk, and the engine remains durable even with prolonged 92-octane use. In short, check the facts, stick with 92-octane, and you'll have some budget left for other minor repairs.

[StAlina]

As a long-time GL8 owner, I choose 92-octane gasoline purely for cost savings. With 95-octane costing over 1 yuan more per liter, using 92 saves me hundreds annually given my high mileage. This vehicle's engine has simple design with low compression ratio - 92-octane fully meets requirements without causing knocking issues. Don't believe claims about premium fuels being better for cars; it's truly unnecessary. Economic practicality matters more. My car runs perfectly fine on 92-octane for years. Just follow the manual's specifications - if higher octane isn't required, don't bother. Calculate costs clearly - the extra money is better spent on oil changes or maintenance. 92-octane is widely available at nearly all gas stations, making refueling convenient. Long-term engine performance shows no significant difference - just ensure fuel quality isn't adulterated.

[DeHenry]

The old GL8 is fine with 92 octane gasoline. Check the owner's manual or fuel tank label, which usually indicates 92 octane. The engine's compression ratio isn't high, so there's no need to spend extra on 95 octane. There's no performance improvement, and 92 octane works perfectly for city driving. Just be careful not to mistakenly fill up with diesel. 92 octane is more cost-effective.