PASADENA, Calif. — If orange is the new black, then 70 is the new 40. At least that’s what Lily Tomlin and Jane Fonda think. And they are proving it as aging cohorts in Netflix’s “Grace and Frankie,” streaming its second season.

“I think 70, that’s when things started to really happen for me,” says Fonda. For one thing, she’s found happiness, she declares. “Why don’t we just start with that? I mean, sort of knowing what to look for in a partner, for example … having a steady job, a man. I’ve never had to go to a studio every day — for five months. It’s fabulous. When you’re 78, having a steady job like that, I absolutely love it.”

“And then, working for a company where the product that you’re making was released on a Thursday … we were in New York promoting it. The next morning, Friday, we got on a plane to fly to L.A. By the time I got home, I was getting calls and emails from people who already saw the whole Season 1. I mean, to have what to me was like a revolutionary experience like that when you’re my age, that’s pretty great. So I love 70s!”

Tomlin, who’s the less talkative of the two, says that she probably felt the freest in her life when she was 15 and managed to avoid “juvenile delinquency school.” But, she reckons, “The first 20 years of your life everything is so imprinted and you spend the next 20 trying to get that out. The next 20 trying to remember where it all started … I don’t cling to those things in the past. I think I probably had a pretty good time (then). I think I did,” she says.

“Grace and Frankie” is about two very different women who find themselves odd-couple pals when their husbands come out of the closet and leave their wives for each other. The husbands are played by Sam Waterston and Martin Sheen (“West Wing”).

Waterston, who played the stiff Deputy District Attorney Jack McCoy on “Law & Order” for 16 seasons, says people are astonished by the show. “They don’t expect such delicate and difficult and hard subjects as late-in-life sexual orientation changes and divorce and death itself and aging to be funny at all. And so I think people are frankly astonished. They were astonished to see Jack McCoy claiming that he was a homosexual, and they were astonished to see the president of the United States want to marry him.”

Fonda says that not only do she and Tomlin synchronize on the series, they share a special bond in real life. “I love being with her for all kinds of reasons, but she has a funny bone. I come from a long line of depressed people. And she has a true funny bone. That’s one of the reasons I love going to work every day. I get to spend time with somebody whose take on everything comes from a place of funny, which for me is total catharsis,” she says.

“I mean, it’s just fabulous … She jokes a lot with me and I’m so lacking in humor that I think it’s all serious. And then she has to kind of bring me out of it. We have a good time together, and we do have a history together.”

That history dates back to 1980 when the two starred with Dolly Parton in “9 to 5,” a working-girl comedy about three female employees who dream of wreaking revenge on their chauvinist boss. The film was such a success that a TV sitcom and musical followed. Ever since, there’s been talk of a sequel, but so far it’s only talk.

Tomlin and Fonda are conspiring, however, to bring Parton on “Grace and Frankie” as a guest star. But executive producer Marta Kauffman (the real guru behind “Friends”) says now is not the time.

“We’re still, I feel, creating a world, and the world is Grace and Frankie. That’s the world. These are characters you want to know and invest in. And the minute you bring Dolly Parton in — who I love by the way — it’s ‘9 to 5.’ No matter what you do, the thought is, ‘Oh, look, it’s a “9 to 5” reunion!’ And you’re taken out of the show … I will say there will never be a ‘Friends’ reunion movie, but I will not say ‘never’ on the Dolly Parton thing.”

This season, there will be several guest stars including Sam Elliott as Fonda’s new love interest and Amy Madigan as his wife. That’s fine with her, says Fonda, who’s had a crush on Elliott since he starred in “Lifeguard” in 1976. And she’s not the only one, she insists.

“When I was married to my favorite ex-husband, he (Sam) came and visited us. When he came to visit us in Montana, we took him to the ranch-office thing, every woman in the office, I mean, they were panting. It was really … and I thought, ‘Oh, well, OK.’”

Her favorite ex-husband, she adds, is Ted Turner.

So what does it take to be vital and gainfully employed in your 70s? “Health, attitude,” nods Fonda.

“Denial,” says Tomlin.