For 40 years hard-rock legends AC/DC have seemed indestructible.

They even bounced back when their original singer died and delivered their defining album, Back in Black.

Recorded with new frontman Brian Johnson a few months after Bon Scott’s death, it has shifted more than 45million copies and is the second-biggest seller of all time after Michael Jackson’s Thriller.

But news that rhythm guitarist and founding member Malcolm Young, 61, is taking a break due to a serious but unspecified illness has prompted fears that AC/DC are reaching the end of the road after total album sales of 200 million.

Rumours said their plans for a new album and 40th anniversary tour had been scrapped and the band were unlikely to perform or record ever again, even though a studio had been booked in Vancouver to start trying out new material next month.

After an ominous silence, AC/DC finally released a statement reassuring fans they would “continue to make music”.

But with no mention of their eagerly awaited tour.

Now Newcastle-born singer Brian, 66, has revealed how his friend’s illness has thrown plans for the future into doubt.

“I don’t know what happens next,” he says in a gravelly Geordie accent that remains undimmed by 34 years of stardom and a home life in Sarasota, Florida.

“We are just going to take it one day at a time.

 

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"I think we are going to into the studio again anyway just to get together again after four years.

"It’ll feel nice to sit in the same room and knock a few tunes out. We’ll see where we go from there.”

The way that news of Malcolm’s illness leaked out on an Australian radio show has clearly shaken Brian and the band .

“I didn’t know they were going to do that because Malcolm is a very proud man,” he says, grimacing.

“It is a debilitating disease, it’s f***ing horrible and I hate it!

"But I don’t want to say much more than that because Malcolm is a very private guy.”

It’s clear Brian is not ready to give up on the band. But first he is going to be on TV talking about his other passion – fast cars – for a new series called Cars That Rock with Brian Johnson.

Speaking under brilliant blue skies at Goodwood race track, he admits that the show is a world away from his usual comfort zone.

“I’ve never done a TV series in my life. I had no idea what I was doing,” he says.

“But they just let me ramble on in my own crazy passionate way.”

Brian’s childhood dream was to be a racing driver.

 

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