Question: Should I service 'lifetime' transmission fluid?

Ask what changed right before it started. Swap the cheap/easy piece first on the 2022 BMW X3 and see if the fault moves. Don't erase codes until someone who can help has seen them. Post the numbers (or the code) and people can get more specific. Cold start is when I can actually reproduce it.

Intermittent stuff lies if you only catch it once. Loaded-suspension checks on the 2022 BMW X3 catch play that a wheels-hanging inspection misses. You'll know quickly if you're on the wrong tree. On “should i service 'lifetime' transmission fluid,” that was the fork that mattered for me. Parts cannon is a personality type I try to avoid. This is the filter I use when the thread starts repeating itself. I'm in no rush to be a hero on it.

I wouldn't throw parts yet. If a shop can't duplicate it on the 2022 BMW X3, bring a video plus freeze-frame data, not just a story. If the cheap test changes it, stop and reassess. Post the numbers (or the code) and people can get more specific. Your commute and mine probably aren't the same, but the test still applies. That's my plan before I call anyone.

Start with the test that can prove you wrong. Write temp, speed, and in-gear vs coast when the 2022 BMW X3 does it — then decide on parts. That's the branch I'd chase this week. If they can't show the line item, I assume it's hiding. I'd rather pay for diagnosis than a second guess-repair.

If it were in my driveway, two 2022 BMW X3s can feel identical and have different causes, so measure before you copy someone else's repair. If the cheap test changes it, stop and reassess. When does it actually happen? No warning lights, which is why I'm documenting it.