2020 Cadillac XT4 Bulb Size

When I first looked for replacement bulbs for my 2020 Cadillac XT4, I felt overwhelmed by part numbers and abbreviations. Think of this list as a simple map: it pairs each lamp on the XT4 with the bulb size and a quick rule of thumb for where it fits. From my experience, that small clarity saves time at the parts counter and helps avoid returns. As you expand from a single headlight to interior and signal bulbs, the mental model here keeps things consistent — match the socket type and wattage rather than guessing by appearance. I refined these entries by cross-checking owner manuals and hands-on swaps, so the chart aims to be practical and easy to follow. Quick recap: use the chart to identify the right bulb sizes for your 2020 Cadillac XT4, then verify fit before installation. Some links on this page are affiliate links, and I may earn a small commission if you buy through them, at no extra cost to you.