Richard Hammond said he and James May never had any doubts about leaving the BBC to join Jeremy Clarkson after he was let go from Top Gear, and that ending their union would have been "stupid".
The three car enthusiasts are now set to launch their new TV programme, The Grand Tour, which will be available to stream on Amazon Prime Video later this month.
Richard said of himself, Jeremy, James and producer Andy Wilman: "We're better together, the four of us.
"Because we've all four worked - for 28 years in the radio and TV I've done - and the others similarly long times. But what have we ever done, any of us, that has been on this scale if we haven't been together?"
He added: "For whatever reason, as a machine, as a unit we're more than the sum of our parts and to break up would be stupid. Come on, I'll never get the chance to work with another bunch like that lot."
James feels similarly and described their grouping, and all the crew and production staff, as a "big, dysfunctional family".
When asked if the crew does whatever the three presenters want them to, he said: "I don't think the film crew would agree that (they) attend to our every whim. They tolerate us.
"I'm talking about the actual camera and sound people - one of them described us as being like a big dysfunctional family. But it is our dysfunctional family."
He added: "What keeps us there? To be honest, because we still, even after all these years, we still enjoy doing it. You really couldn't do it if you didn't get a bit of a kick out of it, if you didn't have a little bit of an ego, because you have to have one really to appear on the TV, and if we didn't just find it stimulating."
Of their decision to go to Amazon for a new show, Richard said: "There's any way we could have gone with it but having looked at every single option and considered it, this was the best route."
Fans they are hoping to lure from their Top Gear days should not expect any drastic changes, apart from a different format and the fact they now have to pay for an Amazon Prime subscription to watch The Grand Tour.
Richard said: "It has still got to feel like us, because if you liked us, we can't suddenly come back and be completely different.
"I can't be cultured and intelligent; Jeremy can't be mechanically-minded. We have to carry on being what we were in terms of attitude and voice. People have got to find that or they'll wonder where the bloody hell we've gone to. So that can't change, but it's got to be better."
The trio's appeal to audiences largely comes from their mocking camaraderie and banter, something that has not abated following their headline-grabbing display of loyalty.
Richard said of his co-stars: "They're old. They're old and fat. I'm 10 bloody years younger than them, people forget about that. They're very fond about saying, 'it's three fat, old men'.
"Hello! Wait a minute. I'm 46, they are in their 50s. They are ancient. To be fair, they've looked after themselves. Oh no, wait..."
There is no love lost between any of them, as James adds that "everything" irritates him about working with Clarkson and Hammond.
He said: "Really, they're deeply annoying people."
:: The Grand Tour arrives on Amazon Prime Video on Friday November 18, with a new episode released every Friday.