We’ve written in-depth articles about the fuel requirements involving different Cadillac models. In this blog, we’ve compiled this information to answer whether Cadillacs require premium gasoline or whether this is a myth. Here’s a quick summary:
Cadillac generally recommends using premium gasoline (with an octane rating of 91 or 93) for most of its engines. However, some models (such as the Escalade, XT5, XT6, and the SRX) also have engines that can take regular gasoline with 87 octane.
However, that certainly doesn’t tell the full story. Below, we’ll first dive deeper into why one would or wouldn’t need to use regular instead of premium gasoline for their Cadillac. After that, we’ll give you a complete rundown of all the Cadillac models sold in the USA in the past decade or so, and their fuel requirements. Read on!
Why Should or Shouldn’t I Use Premium Gasoline For My Cadillac?
As you saw in the introduction, some models and engines take regular gasoline, whereas others have premium gasoline (either 91-octane or 93-octane) recommended. As a general rule of thumb, Cadillac recommends regular 87-octane gasoline for the smaller V6 engines. On the other hand, they recommend 91 or 93-octane for the larger V8s and the (twin-)turbocharged engines.
We recommend sticking with these recommendations.
Not using premium gasoline when Cadillac recommends it will result in a decrease in performance and possible engine damage. The performance decrease will come from the fact that the engine can’t handle the lower octane grade and, therefore, can’t perform as it’s designed to do.
Using premium gasoline in vehicles that have this gasoline recommended is also especially important in cases where the vehicle is performing, such as when towing or driving uphill.
On the other hand, using premium gasoline in vehicles and engines that have regular 87-octane recommended won’t provide the vehicle with any performance benefits. This is because these engines weren’t designed to use this gasoline. Therefore, follow Cadillac’s recommendations as best as possible.
Fuel Recommendations For Each Cadillac Model
It goes without saying that each Cadillac model, and each generation, has different gasoline requirements. Luckily, we have written articles on this already. You can find extensive articles for each model by clicking on “Read more here” after each model.
Below, you’ll find a quick summary for each model regarding octane recommendations. This list only includes models sold in the United States.
CT4
Cadillac CT4 and CT4-V manufactured between 2020 – 2021 take premium gasoline with an octane rating of 93 or higher. From 2022 onwards, the CT4, CT4-V, and the CT4-V Blackwing have premium gasoline with an octane rating of 91 recommended.
Furthermore, all model years and all engine types of the CT4 are compatible with gasoline that contains a maximum of 15% ethanol (also referred to as E15). Read more here about its fuel requirements.
CT5
Cadillac CT5 and CT5-V manufactured between 2020 – 2021 take premium gasoline with an octane rating of 93 or higher. From 2022 onwards, the CT5, CT5-V, and Blackwing have premium gasoline with an octane rating of 91 recommended.
Furthermore, all model years and all engine types of the CT5 are compatible with gasoline that contains a maximum of 15% ethanol (also referred to as E15). Read more here about its fuel requirements.
CT6
Cadillac CT6 with a 3.6L V6 engine have regular, unleaded gasoline with an octane rating of 87 recommended. Models with a 4.2L twin-turbo V8 have premium, unleaded gasoline with an octane rating of 93 recommended.
Furthermore, all model years can take gasoline with a maximum ethanol percentage of 15%.
CTS
All generations and engine types of the Cadillac CTS can take premium, unleaded gasoline with an octane rating of 91. However, the early 2.6L and 2.8L V6 have 87 octane recommended, whereas other V6s (especially the ones with a turbo) or the V8 engines have 93 octane recommended.
Furthermore, all generations of the Cadillac CTS manufactured from 2008 onwards can take gasoline with a maximum percentage of 15% ethanol (referred to as E-15). Read more here about its fuel requirements.
Escalade
Cadillac Escalades with a 5.3L engine make use of regular unleaded gasoline with an octane of 87. For the 6.0L engine, 91 octane is recommended, and for the 6.2L engine, 93 octane is recommended. Both the 6.0L and 6.2L engines can run on gasoline with an octane as low as 87, although this will cause a decrease in engine performance.
Escalades without a FlexFuel badge or a yellow fuel cap should never use fuel with 15% or more ethanol. E-15 and E-85 are, therefore, not an option, and doing so will damage the car. Escalades are, however, compatible with E-10, which contains 10% ethanol. Read more here about its fuel requirements.
SRX
The 2004-2009 models had two engine types; a 3.6 L V6 with a recommendation for unleaded gasoline with an octane of 87 and a 4.6 L V8 with a recommendation for 91 octane level gas. The 2010-2016 models had three engine options; 2.8 L V6 with 93 octane level premium gas recommended, 3.0 L V6, and 3.6 L V6, which had regular unleaded 87 octane recommended.
Furthermore, the Cadillac SRX can take a maximum of 10% ethanol for all engine types. The only exception to this is if it’s a FlexFuel vehicle which can take ethanol up to 85%. Read more here about its fuel requirements.
XT4
Cadillac XT4 manufactured between 2019 – 2021 take premium gasoline with an octane rating of 93 or higher. From 2022 onwards, the XT4 has premium gasoline with an octane rating of 91 recommended.
Furthermore, all model years of the XT4 are compatible with gasoline that contains a maximum of 15% ethanol (also referred to as E15). Read more here about its fuel requirements.
XT5
Cadillac XT5, with a 3.6L engine, take regular unleaded gasoline with a minimum octane rating of 87. XT5, with a 2.0L engine, take premium unleaded gasoline with an octane rating of 91.
Furthermore, all model years of the XT5 are compatible with gasoline that contains a maximum of 15% ethanol (also referred to as E15). Read more here about its fuel requirements.
XT6
Cadillac XT6, with a 3.6L engine, take regular unleaded gasoline with an octane rating of 87. XT6, with a 2.0L engine, take premium gasoline with an octane rating of 91. Furthermore, all model years of the XT6 are compatible with gasoline that contains a maximum of 15% ethanol (also referred to as E15). Read more here about its fuel requirements.
What Other Things To Consider When Refueling Your Cadillac?
Besides the octane and ethanol levels, there are other things to consider when refueling. Two of the most common things that should be taken into account are the use of additives and where you get your gasoline from (yes, there are differences between retailers).
Aftermarket additives are available in places like Amazon and are marketed as either being performance-enhancing or as a helpful substance that cleans the internals of your engine. However, Cadillac strictly recommends against the use of aftermarket additives.
This is because these additives may contain silicon or metallic pieces that actually harm your engine more than they clean it. This is damage that’s not covered by any warranty. Furthermore, using gasoline from the correct retailer will provide your engine with all the fuel additives it needs.
For this reason, Cadillac recommends using gasoline from TOP TIER retailers. You can find a retailer like this at toptiergas.com. TOP TIER is an initiative that several large carmakers in the United States support. Gasoline from these retailers has a higher amount of additives that have proven to keep your engine much cleaner in the long run. Below, you can see the difference between TOP TIER and non-TOP TIER gasoline.
If TOP TIER gasoline isn’t available in your area, Cadillac codes have certain recommendations for additives that they sell themselves. You can find this information in the corresponding articles for each model, in the owner’s manual, or by talking to a salesperson.
What If I Hear A Knocking Sound From The Engine?
Furthermore, using fuels with an octane rating lower than 87 in any Cadillac will result in severe damage to the engine, which is indicated by a symptom referred to as engine knock.
Engine knock means that the fuel can’t be adequately burned, resulting in a heavy knocking sound of the engine. A slight knocking sound is never a problem, but heavy knocking should be dealt with immediately.
Please stop the vehicle and contact your dealers if this heavy knocking occurs. You’re likely using fuel with a lower-than-recommended octane rating. The car needs to be drained, the fuel filter will need to be replaced, and the battery will need to be disconnected and reconnected to reset the car’s memory.
Hi! My name is Stefan; I’m the owner and lead writer at TheDriverAdviser.com.
I’m an active writer on this blog myself, as well as a novice car mechanic. For the really technical stuff, I find writers with experience as a mechanic or who have studied mechanical engineering.
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