This is _very_ noticeable with buses. My local transport system uses a mixture of modern-ish (last 10 years) diesels, heavy/plugin serial-hybrid, BEV, and a sma

This is _very_ noticeable with buses. My local transport system uses a mixture of modern-ish (last 10 years) diesels, heavy/plugin serial-hybrid, BEV, and a small number of ancient (20 year old) diesels, all double decker. The BEVs are a shockingly different experience from the old diesels, noise and vibration-wise. (The most disconcerting are the hybrids, which go from near-silent to very noisy and back periodically.)