Home » Every 2019 Cadillac XT4 Will Feature Capless Fuel Fill

Every 2019 Cadillac XT4 Will Feature Capless Fuel Fill

Every 2019 Cadillac XT4 Will Feature Capless Fuel Fill

When the 2019 Cadillac XT4 launches this fall, it will introduce many new features and technologies that customers will notice the minute they enter the small crossover. And when it comes time to refuel, they’ll see another one – a capless fuel filler system.

What It Is

It’s highly likely that owners of modern Cadillac vehicles are familiar with the capless fuel fill feature, which makes refueling simpler and more convenient since it removes the traditional twist-off cap hidden behind a vehicle’s fuel door.

Instead, one only needs to open the fuel door, insert the fuel nozzle, and begin fueling. When finished, simply reverse those steps, without having to fumble with the gas cap.

Capless fuel fill on 2018 Cadillac CT6

How It Works

Cadillac’s capless fuel system has two “flaps” (or doors) inside the filler tube, designed to lock fuel in with a rubber seal around its edges and ensure that the system remains air-tight. When a nozzle is inserted in to the filler chamber, it pushes aside those two flaps.

And that is where Cadillac’s capless system shines. Though capless fuel  feature have been around for roughly a decade, not all are made equal.

While Cadillac’s system has two flaps within the filler chamber, many capless systems from other automakers only have one such flap/door, making them vulnerable to fuel leaks. What’s more, Cadillac’s system also has no internal drain, something that can also lead to inadvertent dripping of fuel.

Owner Benefits

Besides the obvious benefit of greater convenience, capless fuel fill has a host of advantages for both the car and the driver.

Benefits for driver:

  • Keeps hands clean, free of dirt and fuel
  • Eliminates risk of leaving gas station with dangling gas gap

Benefits for car:

  • Keeps paint clean, free of fuel and scratches caused by swinging gas cap
  • Keeps engine running smoothly (see below)
  • Can enable a smaller fuel door, since the door no longer needs to accommodate a hand, thereby making it less noticeable

The notion that a capless fuel fill system can keep an engine running smoothly typically raises questions from some, so we thought we’d address it before you ask in the comments.

Simply put, fuel systems must be fully sealed, and a loose cap can trigger a “check engine” light, thereby leading to a service visit. A capless system eliminates the possibility of a loose gas cap.


All models and trim levels of the 2019 Cadillac XT4 will have capless fuel fill as standard, including the base XT4 Luxury as well as the up-level XT4 Premium Luxury and XT4 Sport.

Notably, the first Cadillac to feature capless fuel fill was the 2013 XTS Sedan. From there, the feature proliferated to all modern Cadillac models except for the ATS Sedan. With the discontinuation of the ATS Sedan after 2018, all 2019 model year Cadillac vehicles are equipped with capless fuel fill as standard.

Written by
Alex is the founder of Cadillac Society. He has a deep passion for automotive business strategy and enjoys driving his ATS sedan on twisty mountain roads.


  1. The XT4 fuel filler is on the wrong side of the car (Pass side)

    • Why is the passenger side the “wrong side”, all of a sudden?

      It’s on the passenger side of the car for a reason: when you run out of gas and are stranded on the side of the road, you’re not filling up while standing on the road, thereby significantly minimizing the chances of being hit (and therefore injured or killed) by a passing car.

      This is the reason that the fuel door is on the passenger side of the car on the ATS, CTS and CT6, as well as the upcoming CT5. This is also the reason that every single German vehicle has the gas door on the passenger side of the car, too.

      • I have noticed that most CUVs and SUVs have their gas filler doors on the passenger side, but my 1995 Buick Regal and most other sedans have it on the driver’s side. Maybe sedans usually carry only the drivers. I do prefer it on the passenger side.

  2. Is it possible that the exterior and/or the interior colors will change or increase prior to the release of the XT4 ?

    • Not for the 2019 model year, no.

      PS: in the future, please start a new thread for a topic like this in the Cadillac Society forum. It helps keep discussion organized 🙂

  3. Makes me wonder with capless fuel doors that comes with two doors, is it foolproof from anyone trying to slip something in the gas tank or try to siphon gas out of the car?

    • Cadillac started including a locking gas door in vehicles with the capless fueling feature around 2016-2017 model years, so anyone trying to pull gas out of the tank or put something in it would first need to get past that obstacle.

      But if one does get past the locking gas door, then they would need 1) an object to push the two flaps inside the chamber aside, and 2) a long-neck hose to keep both of the flaps pushed out. In other words, you can’t just do it with a hand or finger.

      So, what you describe is not impossible… but neither is it impossible with a vehicle that has a “regular” cap.

      • I have seen what looks like a special long necked funnel sold for capless fill systems when the owner has to add gasoline from a container. Maybe with such a funnel inserted, a small hose can be passed through the funnel to siphon out fuels? Or does the system add a special perforated blocker to allow liquids to flow but no solid items to pass?

        • Right, the long funnels are used in case one has run out of gas and needs to use the portable canisters. That’s the way to push through the doors/valves of the capless system and fuel on the side of the road, for instance.

          So I guess one can siphon fuel out that way… but the point remains that to siphon out fuel from this system, one will need to get past the locking fuel door and have the long funnel with them.

          In any event, the capless fuel systems make it just as easy (or just as hard) to steal fuel from a car as the traditional systems with caps, making the topic moot.

          In both cases, if someone is truly determined to siphon fuel, then they will need to be prepared to do so. But in my years of car ownership, I have never had a problem with someone siphoning fuel from my car, or from the cars of those I know.

          • There is a section in the tank from the filler tube that makes siphoning gas very.very difficult. The hose you insert would go in a upward direction where there is no gas.

      • No locking door on XT4’s

  4. I bought an XT4 a month ago. I am using premium gas as recommended. Every time I get gas my “check engine” light comes on, it sometimes go off. I had OnStar do a diagnostics & it is related to gas filling. Anyone else having this issue?

  5. I have an XT4, Evey time i wash the vehicle there is a slight amount of water in the area where the gas tank spout would go into the capless hole. Wondering if that water (very little) overtime would get into the gas tank itself. I know what Cadillac would say, what do you guys/gals think?

  6. I really hate that capless gas cap. On my XT4, 22` it broke down at 2,500 miles (first cap fell off). This capless system is of really poor design and quality. There is no way to reattach the cap, you can only replace the entire assembly (Part #84753599). Hope I’ll get the defective part and I’ll try to build myself a conversion kit to a standard gas cap. The warranty is 3 years and this thing definitely won’t last long – only 2,500ml in my case and I´m sure it will break down again.


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