How Jeep Design and Engineering Faced off on the New Grand Cherokee
If the 2022 Jeep Grand Cherokee were a child, chief engineer Tom Seel and lead designer Mark Allen would be dedicated but disparate co-parents doing the best they can for the sake of their progeny. One parent is happy to let the kid play more hours of video games. The other wants him to read more books. Families that have it figured it out know how to work together for the most positive outcome.
It’s not always easy for the design team and engineering team to mesh when they’re looking at a vehicle project from different perspectives. Seel and Allen, each a Jeep veteran for decades, understand when to lean in and when to let the other lead.
“If developing a car were easy, we’d put together a spreadsheet and go,” Seel told me at a sit-down in Moab, Utah, where I had a chance to put the new Grand Cherokee through its paces. “But it’s not like that. There are constant balances and tradeoffs, and we did have a few –“
“ –tense moments?” Allen breaks in with a grin. Seel agrees, emphasizing that no one took any conflict personally. It was all about what was right for the car, the two of them acting as co-guardians.
“It will sound corny, but the Jeep always had to win; it wasn’t me or him,” Allen says. “Tension builds between design and engineering, but the car has got to be first.”
From all sides, the Jeep team knows the Grand Cherokee is a staple product, the heritage of which dates back nearly 30 years. If one end of the Jeep spectrum is the Wrangler, the other is most certainly the Grand Cherokee, Allen says. When the planning process started for a bottom-up redesign for the popular two-row SUV, former Jeep boss Mike Manley pushed hard for off-roading improvements. Allen believes the new version achieved this goal, particularly in the articulation, and he says it has a more comfortable ride than the previous generation.
Stretching the Boundaries
For model year 2022, the Grand Cherokee is longer and wider, with 3.7 inches in the back and close to two inches in the wheelbase. That alone was a vigorous tug of war; at different parts during the process, either the design team or engineering team would have to give, and the difference could be as tiny as a single millimeter. Allen was passionate about increasing the track by 36 millimeters (18 millimeters on each side) to give the Grand Cherokee a more planted feel, and it was on him to convince the engineering team it was a worthwhile change.
“That’s me sticking my nose into a lot of technical issues: suspension, steering, and so on,” Allen says. “Really, when you’re architecting a suspension, the appearance is at the bottom of the list, and Tom helped me get it where I wanted it.”
The new axle-on-engine structure also helped Allen’s design team by lowering the engine by 40 millimeters, which improves the dynamics and balance of the SUV.
Headlighting was also a challenge. Typically, Jeep builds a base level and a luxury level headlight; Allen suggested it would be easier (and better for the design) for every Grand Cherokee to wear the same headlamp. The engineering team agreed. By going to LEDs across the board and adding the signature upper brow, both Seel and Allen were satisfied. The idea met all the cost objectives and thematically still worked.
Painting the Roof
The next hurdle was agreeing on the roof color, and Allen made the case for all of Grand Cherokee trims to come with a black top. However, that added another layer of complexity because vehicles with a black roof would have to go through the paint shop twice, adding time and assembly line mileage.
When a roof is a different paint color than the body, the top is painted first in a separate spur line, then it’s taped up and goes back through the line for the body color. Taping the car is a manual process during which an assembly worker circles the vehicle with a sophisticated tape gun; operators have just a few minutes to complete the task. Doing this for every Grand Cherokee wouldn’t be ideal for achieving manufacturing goals.
Even the way the tape is applied has to be reviewed with an extensive amount of engineering to determine where every one of those tape lines goes. The goal is for it to look perfect while matching throughput numbers, so they had to collectively work together to ensure the person who is wielding the tape gun and pulling the tape can do it efficiently and effectively at X jobs per hour.
“It came down to bringing advanced manufacturing into the fold,” Seel says. “They’d say, ‘Well, we can do that, but we can only do a certain number of those to maintain the throughput.’ Then it became the discussion of which trims made the most sense for the paint process.”
Crunching the numbers, the team agreed to make the black roof optional on the Overland and standard on the Trailhawk and Summit variants. That way, the manufacturing team could meet its goals for output, the engineering team could keep watch over the process, and the design team was satisfied with the collaboration. Allen says that required a little horse trading.
“You’ll notice the car doesn’t have body-colored mirrors,” he says. “We decided to make all the mirrors black, and what that did was reduce the part count. For instance, there’s a base mirror, one with the turn signal, one with a sensor, and so on. Multiply that times nine colors. How many mirrors did we knock out of there by doing all-black mirrors? A lot.”
With that proposal, the team realized they could go from over 350 types of mirrors down to 19. From a manufacturing perspective, each mirror has to be warehoused, displayed, and on sequence so the assembly team can pick and place it. Having fewer choices streamlines the production line significantly, and from a design perspective it gives the new Grand Cherokee a more “technical” look, Allen says.
Both Seel and Allen agree that their baby is growing up, and with parents so committed to its development, it’s all but guaranteed to continue Jeep’s record of success with this SUV.
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