Cadillac Fuel Requirements

Many Cadillac vehicles are equipped with high performance engines that require premium gas to run efficiently. Cadillac has five models of cars including the CTS, SRX, Escalade, DTS and STS and each has different fuel octane requirements based on the engine size and type. In general, Cadillac vehicles use either premium, mid-grade or E85 fuel, instead of regular gas.

Premium Fuel

Fuel with a higher octane rating of 91 or more is usually considered premium fuel, as it has fewer additives than regular unleaded gasoline. The vehicles that require premium fuel in the Cadillac line up are the Cadillac SRX 2.8L V6 engine, the Cadillac CTS 6.2L V8 engine, all models of the Cadillac Escalade and all models of the Cadillac DTS. For the SRX 2.8L V-6 and the Cadillac CTS 6.2L V-8 , Cadillac recommends the use of 93 octane premium fuel for the best engine performance, but if it cannot be found, then 91 octane fuel can be used. According to the users' manuals for these vehicles, regular grade 87 octane fuel can be used in an emergency, but if it is used, then aggressive driving should be avoided to prevent knocking and permanent engine damage.

Mid-Grade Fuel

Some Cadillac vehicles can use mid-grade fuel rated at 87 octane. These vehicles include the Cadillac SRX 3.0 V-6, the Cadillac CTS V-6 and all models of Cadillac STS. According to the users' manual, using gasoline less than 87 octane in any of these vehicles can result in engine knocking.

Flex Fuel

Some models of the Cadillac SRX, Cadillac XT5 and Cadillac Escalade are considered Flex Fuel vehicles and will display a Flex Fuel badge on the vehicle and a yellow fuel cap. These vehicles can use premium gas or the lower octane 87 octane gasoline in the gas tank and still get roughly the same MPG. Cadillac encourages the use of E85 in these vehicles as a more environmentally friendly choice. The users' manual warns that vehicles designed for E85 cannot use fuel that contains methanol because it will damage plastic and rubber parts, and this damage would not be covered under the warranty.

Top Tier Detergent Gasoline

For all of its vehicles, excluding the Flex Fuel vehicles, Cadillac recommends the use of Top Tier Detergent gasoline for the best performance. If the gas is rated Top Tier it will displayed on a label on the gas pump. If Top Tier gasoline is not available, then Cadillac recommends that GM Fuel System Treatment Plus be added each oil change to help remove deposits. In areas where gasoline is oxygenated with ether or ethanol, Cadillac recommends their use while still complying with the octane needs of the vehicle.