"No, there wasn't a bus route directly from Cramlington to Sunderland via the Tyne Tunnel in the 1980s" says Google.
That said they are using AI which is often wrong!
But I certainly don't remember it if there was.
I have to admit however that I haven't been on a bus "since Moses was a lad". An exaggeration of course but truly since I was 35 the only occasion on which I have used a bus is in London about 10 years ago (free with my Derbyshire Gold Card which us old folk get for free)