After 12 years striving in Formula One, including five years of intense rivalry with his Red Bull teammate Sebastian Vettel, the popular racer finally won his first world title in 2015.
The no-nonsense Australian might appreciate the irony that the victory laurels came in the World Endurance Championship (WEC), where staying power is part of the game, rather than the fast-paced world of F1.
"The biggest challenge for me is dealing with the traffic," Webber explains. "There's a lot of different categories in WEC racing."
The WEC is a bit like driving on the freeway -- there are slow cars, fast drivers and a plenty of people in between, some of whom may or may not know which lane they should be in.
The championship has four classes, all racing at different top speeds, from the futuristic LMP1 prototype racers to the GTE Pro-Am sports car category which pairs amateur drivers with professionals.
At Silverstone there will be 33 cars on the grid, compared to a maximum of 22 cars in F1 this season, and for June's legendary Le Mans 24-hour race the field increases to 60.
"I race in the LMP1 category and we're arguably the fastest drivers and the fastest cars, but we've got to deal with amateurs sprinkled through the race," Webber says.
"Le Mans has always been like that, mixing professional and 'gentlemen' racers, but that's been a mind shift for me."
Share and share alike
"The individual side of F1 is so intense but I now enjoy sharing the car with two other teammates," says Webber, who won the 2015 world title with New Zealander Brendon Hartley and German Timo Bernhard.
It's not unusual to find F1 drivers locked in a duel with the man on the other side of the garage -- just ask Mercedes rivals Lewis Hamilton and Nico Rosberg
-- but teamwork is the essence of endurance racing.
Individuals must abandon their egos as two or three drivers share driving duties for each team. Every WEC race in 2016 lasts six hours, with the exception of Le Mans. In the top category, each racer must drive for at least 40 minutes but no more than four and a half hours.
"We like to contribute and pull together," Webber says. "We talk and help each other as much as we can to get the most out of the car. But we also want to make the car know who is behind the wheel, so we've all got different driving styles which we like to keep to ourselves!"
Brain and brawn
Webber reckons endurance racing saps more brain juice than an F1 race, which has a two-hour maximum limit.
"Mentally it's more draining because the races are a lot longer," says the 39-year-old, whose best finish in the F1 championship was third overall, which he managed three times.
"At a race like Le Mans you have a 90-minute sleep in 30 hours and you drive for eight hours, so that's quite a draining day.
"You also have to deal with the backmarkers, race at night and use another driver's car setup, which can also be less comfortable."
"I was way too big and too tall for F1," Webber reveals. "I had to stay as lean as I could my whole career, but still stay fit enough and strong enough to hang onto the car for two hours."
At six feet tall, he weighed around 11st 11lb (75 kg) when at Red Bull -- more than 10 kg heavier than what he once called the ideal driver weight.
"Now I have a little bit of room to move, a couple of kilos, which probably doesn't sound much but it's nice that you can have that because the overall weight of the car is that little bit more," says Webber, confessing his love for ice cream, chocolate and "a bit of red wine here and there."
The Porsche LMP1 hybrid car has a minimum weight of 875 kilos compared to 702 kilos for an F1 car, meaning a difference not only in the size demands of the drivers but also in the physical dynamics they must deal with on the track.
"The g-forces on the body are lower," the nine-time Grand Prix winner adds. "The heart rate is also lower, so in that endurance racing is easier than F1."
The Davis Cup of motorsport
The 2016 F1 season will have a record 21 grands prix, spanning 252 days.
In contrast, there are nine stops on the 2016 WEC calendar, which focuses on its jewel in the crown, Le Mans. Each stop, from Great Britain to Bahrain, is also an important market for its global car manufacturers such as Porsche, Audi and Ferrari.
A new race in Mexico City is scheduled for September at the Autodromo Hermanos Rodriguez, which also hosts F1 and Formula E.
"In F1 you are racing week in and week out against the best guys on the hardest tracks in the world," Webber says.
"That went on for a long period of time for me, now I can do nine races a year with a phenomenal brand and share that with my teammates. It's a bit like the Davis Cup
(international teams event) in tennis.
"We can travel and really enjoy it, but when we've got our helmets on, the racing is very competitive and we want to win."
"The thing I miss most about F1 is working with the likes of (Red Bull chief technical officer) Adrian Newey," Webber says. "F1 is renowned for its arms race. It's rewarding being involved in that pace and intensity."
While F1 remains the pinnacle of motorsport, showcasing the most technically advanced and fastest vehicles on the planet, auto manufacturers like Porsche, Audi and Toyota are increasingly using the WEC championship, now in its fifth season, as a serious test bed for road car technology.
The very essence of the LMP1 class, after all, is to produce a high-tech, closed-cockpit prototype and, unlike F1, each team also has the freedom to choose which hybrid system it uses to power the car.
"Porsche has brilliant engineers and the same intensity in terms of development," Webber adds. "The experience I have from F1 is to bring accuracy from a driver's perspective to that research and development.
"Where motorsport is going to be in 30 years, given road car developments, is our fascinating challenge.
"But it's just very hard to sign off (new parts) so aggressively in WEC compared to F1 because the races are so long. The cars have to be validated in a very safe fashion, in the same way an airplane has to be."
Webber wins again?
Though he will turn 40 in August, Webber shows no signs of slowing down -- and he is aware that he needs to make the most of his remaining racing opportunities at Porsche.
He's now in the final season of his three-year deal with the German manufacturer, and will be seeking his first victory in the famed Le Mans 24 Hours after finishing second behind a Porsche team led by current F1 driver Nico Hulkenberg last year.
"It takes a lot of preparation and effort in this type of racing," Webber says.
"But when you get older finishing second really sucks... you want to be winning as often as possible."