Leyland always make the noisy engine which I can’t stand hearing
it loud~ Now that Leylands are retired, all Singapore buses except
KUB are safe~
The relatively new single deck scanias are arguably noisier on
the inside and outside.
And the volvo double deck B9TL (the first wheelchair assessible
double deck) is a major source of noise pollution.
The old LO3x and VO3x models are less noisy than this horrid
model.