Breaking into Hollywood was a struggle for the young Vin Diesel until a short film of his got the attention of Steven Spielberg. He ended up being cast in 1998's Saving Private Ryan. A few years later, he hit the jackpot with the Fast and Furious franchise. And the rest, as they say, is history.

Diesel projects a tough guy, a devoted family man kind of image. He has a staff that pushes this image on social media. But is it real? Some say NO.

He has a reputation for being difficult to work with. He is said to be demanding and less than hard working. Many of his co-stars and most of the crews in his films don't like him. Does he care? Apparently not. He can ride the Fast and Furious franchise out to its end, whenever that may be, and then sit and quietly count his hundreds of millions of dollars.

So what are his "not-so-sweet" secrets? Read on. Here are 15 of them that may surprise you, maybe even shock you a little.

15 He's A Cheater

Vin Diesel is known to be a flirtatious come hither kind of guy. He tries hard to pass himself off as a family man. But according to a "source": "About a year ago, he met this girl at a party in NYC. They hit it off, one thing led to another. . .  Vin and the woman had a whirlwind romance, based on sex." Some say that wasn't the only time the guy has done the dirties on the mother of his three kids, model Paloma Jimenez.

14 The Guy's A Party-All-Night Fiend

Stories of Vin Diesel's party-hard ways have been around for a while. It's said he's never on time for early morning meetings on sets because he's sleeping off yet another all-night session. He parties in Miami. He parties on yachts. Vinnie parties just about anywhere and everywhere. And if you are thinking that impact his famous physique, you would be right. It's called the party bod. So much for the tough guy thing.

13 Throws His Weight Around On Set

He's got a co-producer credit on some of the Fast and Furious films. And if you think it goes to his head you would be right. He changes meeting times to suit his party lifestyle. He makes certain his shooting schedule is a fairly leisurely one. And he makes decisions about what will and won't happen in the film. It annoys the sh** out of the cast and crew.

12 Keeps Cast/Crew Waiting While He Sits In His $1.1 Million Trailer

When an actor says he's going to his on-set trailer, what do you think of? Well, it's probably not an 11oo square foot custom-built gold abode with $70K worth of technology, round the clock video surveillance, and granite countertops in the kitchen. And he takes it with him when he shoots a movie, wherever it is. And he loves it so much he doesn't mind keeping the cast and crew waiting while he chills out inside.

11 Demands Special Perks On Set

OK. Silly picture. But the point is Diesel demands special treatment on the set. If everyone is piling into a van to travel to a filming site, he might ask for a private helicopter to transport him. And even then, he would probably be late. And of course, the filmmakers have to foot the bill for transporting and setting up his precious trailer. The tiger is pretty cool, isn't it?

10 7 A.M. Meeting? Forget It. Try 10 A.M. And I'll Be There

We're not saying Vin Diesel is lazy. Well, not exactly. But he likes to pace himself. Why shoot for 8 hours a day when they can shoot around you and you can roll up and do a quick hour or two. And why on earth would he want to show up for a meeting at 7 a.m. when 10 gives him more time for his beauty sleep. Or his hangover cure.

9 His Own Publicity Team Dumped Him

While the rest of the cast was busy promoting 2009's Fast & Furious, Vin was ignoring calls and pleading illness. Says one source, he finally arrived for a press event nearly four hours late looking fit as a fiddle. He was gracious enough to do an hour or two of face-to-face with the press. After this little stunt, his publicist firm dropped him as a client. About time too.

8 Pretends He And Paul Walker Were Best Buds - Not

Since Paul Walker's untimely death in 2013 Vin Diesel has gone on and on about what great buddies they were. Says one source: "Some insiders say that Diesel's outspoken dedication to Walker would come as a shock to the late actor because they didn't get along behind the scenes." In 2013 Diesel show up in tears at the location of the car crash that killed Walker. Fake, fake, fake says Walker's friends.

7 Exploits Walker's Memory With Tributes That Walker's Friends Hate

Walker's friends point to Vin Diesel's hypocrisy as far as his many, many tributes to Paul Walker are concerned. They swear blind Diesel was nasty to the dead actor and that all his effusive tributes to Walker are either a blatant lie or the result of a guilty conscience. It will not surprise anyone that the crew and stuntmen on the Fast and Furious films were Paul's natural buds, not the likes of Diesel.

RELATED: 15 Unknown Facts About Paul Walker

6 The Guy Criticizes Other Actors' Performances

With his co-producer clout on the Fast and Furious films, he sees fit to wade in and comment on the performances of his fellow actors. Well, he does on the rare occasion he shows up for the day. He even had the nerve to criticize Dwayne "The Rock" Johnson and Charlize Theron's acting. That's either very brave or very stupid. Very few of his co-stars have anything nice to say about the guy.

5 Slob Bod: Head Imposed On Double's Body

For 2017's xXx: The Return of Xander Cage Vin was up to his old party hard ways, keeping people waiting the next day while he slept it off in his trailer. All this partying took its toll. According to one source, his head was "superimposed on his stunt double's body for the majority of the movie, as his physique was not good enough." No wonder he is nobody's favorite co-star.

4 Film Crews Hate Him

Vin Diesel shows up late, makes demands, throws his weight around, and dares to criticize The Rock. So what do film crews think? Which side are they on? It will surprise no one that to a man and a woman they back the hard-working, on-time, good-natured Rock over Vin Diesel any day of the week. It's not just the film crews that dislike Diesel. His co-stars aren't that crazy about the guy either.

RELATED: Fast & Furious: 15 Things That Never Made Sense About The Races

3 Most Of His Co-Stars Aren't That Crazy About Him

2 That Awful Feud With Dwayne Johnson

The infamous feud between Diesel and Dwayne "The Rock" Johnson" reportedly started on the set of The Fate of the Furious.  The Rock took to Instagram to complain about "unprofessional" behavior, referring to some of his male co-stars as a "candya**". He was referring to Diesel.  Johnson is apparently everything Diesel isn't: Prompt, friendly, prepared, and ready to muck in. The feud was nasty, nasty.

RELATED: 15 Things Dwayne The Rock Johnson Does To Stay In Shape

1 Don't Get Between Him And What He Wants

Vin Diesel is out for himself, plain and simple. He is a "what's in it for me" kind of guy. He's prepared to throw his box office weight around to get what he wants, whether that is special perks on sets or co-producer status. It's about money, but it's also about power, clout. He will stop at nothing to get what he wants. Sounds strong? Well, read back over this piece and draw your own conclusions.

NEXT: 17 Details About The Making Of The Fast And Furious Films