When we had 2 Spitfires they were “the red one” and “the blue one” for ease of reference.
Since we’ve had larger vehicles to cart my son’s wheelchair we’ve had:
Big Brown Bus (was initially called Shit box till kids got older, occasionally Dirt Box)
Big Blue Bus
Big Grey Bus
Big Blue Bus
Had a 308SW with the suffix “ODV” which my daughter thought hilarious to call “Old Daddy’s Van”
Left a job with co car 2 years ago so had to get something pdq- ended up with a Golf in poverty spec grey, grey interior & grey gti wheels a PO fitted. So my son calls it Daddy’s Dung Heap ‘cos he wants me to get a “German Whip”.
bikes just referred to by brand/model or type eg full suss or hardtail.
This subject came up with some riding buddies who named their bikes. I had a Palomino at the time and they missed the joke when I said mine was called Patsy.