Deep inside General Motors Vehicle Engineering Center in Warren, Michigan, is a storage room few people know about.
In that room, a handful of engineers for two years hid the secret weapon GM would have in the current Truck Wars: The MultiPro tailgate on the 2019 GMC Sierra SLT and Denali pickups.
"We had a 3D-printed version of the tailgate that we kept covered with a lock on the door. We'd put it on a gurney and wheel it in the conference room to work on it, then wheel it back to the storage room," said Derek Patterson, GM's lead integration engineer on the MultiPro tailgate. "We did this all in secret. I kept a list of those who knew about it. No one ever showed anything over Skype."
The tailgate was so guarded because it is revolutionary. Many auto experts say the MultiPro gives GM an edge in one of the U.S.'s most competitive and profitable vehicle segments. To prove it, just look at GM's aggressive advertising of the tailgate.
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The story behind this arguably ingenious invention started a decade ago when a GM manager asked a high-school-educated technician, Jim Gobart, to fix a problem.
Stairway to heaven
The MultiPro tailgate is essentially two tailgates in one. The primary gate is hinged like a conventional tailgate. Then, a smaller inner gate is hinged within the primary gate panel. When a person raises or lowers these two tailgate panels in different combinations, the MultiPro can act as:
It comes standard on the GMC Sierra SLT and Denali.
In 2009, Gobart's job at GM was as a technician to devise ways to improve GM cars and trucks.
One day, Gobart's manager complained to him, "Every time I take a pickup to Home Depot and load it with items, by the time I get home, the stuff has slid forward and I can't reach it," Gobart recalled.
Gobart said he had some ideas, and just a few days later, pitched them to his boss.
"If I could take the tailgate, which is about two feet tall, fold it in half horizontally, then fold the second part down, you could reach in further in the truck," Gobart remembers saying. "Then I thought, if I put another flap on the inside of that and it folds out horizontal, you now have a stair step. I thought that would be very nice for someone who works out of the back of that truck."
His idea blossomed as he concocted more ways to configure the tailgate to provide seating and storage.
"I nicknamed it 'Stairway to Heaven' after the Led Zeppelin song because I thought I would want it and the customer would certainly want it," said Gobart.
His boss liked it and told him to do a "quick and dirty" mock version to determine if the idea was feasible or laughable.
So Gobart got two tailgates from GM's pickup group. It took him about a month to cut them up and combine them into one folding tailgate, but the early iteration of the MultiPro tailgate was born.
"It went over very well," said Gobart. "GM leaders thought it was a great idea and everyone wanted one."
But there were a few obstacles that would delay it for a full decade. First, this was 2009, the height of the Great Recession and as GM entered bankruptcy, so justifying the steep cost to engineer, design and build such an elaborate tailgate was not going to happen.
Second, GM wanted it on the GMC Sierra, which was in the middle of its product cycle. It did not make sense to introduce an innovative tailgate on a design that would soon be outdated.
Finally, it needed refinement and a lot of durability testing. By the time the tailgate was ready for production, it would be the most tested tailgate in GM's history.
GM's 'Shark Tank'
"Jim's idea of breaking it in half made it very accessible and versatile. But I had issues with the hatches holding it together," said Patterson.
So in the first quarter of 2014, Patterson took the idea to a GM Innovation Clinic for input.
"Think of that as 'Shark Tank,'" said Patterson, referring to the television program where entrepreneurs pitch their business idea to a panel of wealthy investors hoping to win financial backing.
GM started the clinics and the Innovation Hub, a group that works to inspire GM employees to contribute creative ideas, in 2014.
"The seat-back storage, some of the advanced trailering on the Sierra, it all came from that clinic," said Patterson. "You had people there from all different aspects" of GM.
Out of the clinic came ideas for improvements to Gobart's tailgate, such as better ergonomics to prevent consumers from bumping their arm.
"We asked Jim to build us another one we can show our customers," said Patterson. "He said, 'OK, I need five end-gates, seven handles and a large pizza.'"
A young inventor
Gobart, 69, is a mild-mannered, modest man who happens to be as original as the tailgate he invented, Patterson said of working with Gobart.
Gobart's name is on 11 patents with GM, including the patent on the MultiPro tailgate along with Albert Butlin, who invented the latching for it. Gobart's name is on eight more patents that are pending, he said.
Gobart has no college degree. He races endurance motorcycles and snowmobiles, plays on half a dozen softball teams at once and builds anything he can by hand. In fact, Gobart hand-built the sprawling ranch home in Oakland Township, Michigan, where he and his wife live and raised their two daughters.
He knows the power of innovation and secrets too. His father worked on the U.S. space program in the 1960s and Gobart remembers that dad "couldn't talk about stuff."
But Dad's work sure did rock Gobart's world growing up near the Kennedy Space Center in Florida. As a 10-year-old boy, he remembers frequently waking in the middle of the night, "and the house would be shaking and vibrating and you'd looked outside and it was bright as daylight and there was a missile launching into space."
That space-age progress exploding outside his bedroom inspired the young inventor. By early high school, Gobart could build an entire car by hand. Since then, he's hand-built at least 200 cars, he said.
He also has the rare ability to operate an English wheel. An English wheel is a metalworking tool that creates different types of curves from flat sheets of aluminum and steel for building cars by hand. GM found itself struggling to find an English wheel operator in the mid-1970s. In 1978, Gobart interviewed for the job.
"They walked out to the parking lot and saw the car I built by hand and hired me on the spot," said Gobart.
Not only can he operate an English wheel, but, you guessed it, he built the English wheel he uses in his home.
'Begging to buy'
By August 2014, Gobart had built a prototype tailgate that would do all the things the original concept had proposed: Storage, easy access, an entry step, work station and more. GM put it on a 2014 GMC Sierra pickup and in October sent it off to a customer clinic.
"They don't know what company you work for, they just see a curtain around a truck and a tailgate," said Patterson, who was at the clinic. "They all asked 'Who built that?' and I just said, 'Jim.'"
Patterson said some customers were "begging to buy the gate from us at the clinic to put in their own truck. When you have something that hasn't been done before, you start to learn how folks want to use it."
The top three things GM learned from pickup customers were:
"We also used our findings to determine we needed an assist handle," said Patterson. "We had an ergonomist work with us."
By November 2014, GM leaders gave the gate the green light to begin durability tests and production design.
A typical tailgate has one piece, two hinges, two latches and handle, said Gobart.
The MultiPro had a "midgate and the flip-down steps, so you have three times as many hinges and several times more latches and so it's a much more complicated piece of equipment," Gobart said.
It had to be lightweight, strong, durable and cost-efficient, added Patterson.
"We're pretty good at determining how much something is going to cost," Patterson said. "This was unique, but a lot of the pieces on it are parts we use on other products. The stampings, we are very good at that, but there were some other additional things."
He declined to say how much GM spent to develop the tailgate. But engineers built some "mule properties" to test at GM's proving grounds in Milford and its labs. A mule is a rough-built tailgate made with aluminum used to learn how the production gate would act and to correlate those findings against a computer model of the gate.
"We do a lot of analytic testing before we do anything physically," said Patterson. "We made about 23 gates that we put through different forms of testing and correlated that back to our computer model to show that if you load it a certain way it'll dent here, for example."
From October 2014-March 2018, GM conducted "hundreds of tests" to thwart the biggest concern expressed by the customer clinic: "This isn't going to break, is it?"
When asked if the tests proved the gate will hold up over 10 years of ownership, both Patterson and Gobart answer "yes" and "absolutely" in unison.
"When it came to the gate itself, we tested it more than anything else on the truck," said Patterson.
On the road
The 10-person team that started on the MultiPro project grew to more than 100 by the time it was ready for production.
"We always said, 'We're going on the road with the gate to help people understand what is required to get this done,'" said Patterson.
Patterson's team visited GM's lab to make sure there was enough room for testing it and then went to the manufacturing team to explain what it is and what materials will be needed to build it and how it has to be built.
"We did this all in secret. The design was locked down right up until the reveal of it in March 2018," Patterson said. "It was really cool to see that and to hear all the pictures being taken and all the journalists saying, 'How'd you keep this a secret?'"
Even Gobart was amazed that Patterson protected his invention so well for so long.
"With everyone carrying a cellphone these days, you have to do everything on a need-to-know basis," said Gobart. "You can't leave your computer up with the screen showing, you have to shut it down. The fact that Derek and his team could keep it a secret is amazing to me."
'Dad did that'
The two men have worked at GM for a combined 70 years and they agree the MultiPro tailgate was the most challenging and rewarding project of their careers.
For Patterson, whose father had worked at GM in the prototype division, it was satisfying because this tailgate had never been done before, forcing him and the team to be pioneers.
"You're the expert and you can't go look at the last one to see how it was done," said Patterson. "We all grew as a team because of that. And, there's some point when you say, 'Oh, my goodness, this is going to work!'"
Gobart said this invention is at the top of his career achievements, too, despite having worked on the original Saturn and Hummer vehicles years earlier.
"We all work on things that end up on vehicles, but the likelihood that you can stand by and see a vehicle pass you on the road and say to your kids, 'Your dad did that' almost never happens," said Gobart. "To be lucky enough to do what Derek and I did ... I feel incredibly lucky."
Follow Detroit Free Press reporter Jamie L. LaReau on Twitter @jlareauan.
This article originally appeared on Detroit Free Press: GM engineers hid secret tailgate in storage room for 2 years