Catching Up With: GMC Terrain Chief Engineer Mark Cieslak
We find out why the 2018 Terrain is what it is
Automobile Magazine: What's the timeline for Terrain development? When did it begin, where are you presently, and when does it go on sale?
Mark Cieslak: It goes on sale this summer. We started development approximately three years ago. Presently, we are in the final throws of tweaking and refining — bringing closure to the final adjustments.
AM: What is unique to the Terrain versus the Chevrolet Equinox?
MC: The unique selling point with the Terrain is the exterior. We wanted something that is very stunning — bold, confident, and poised. We also knew we needed to compliment that with the interior. Some of the premium materials are unique to the Terrain: the aluminum components and soft-touch areas. The mode switch and the electronic precision switch (push-button transmission) are also unique.
The basic foundation — the architecture — is the same for both vehicles but, as the styling evolved, we started diverging a little from the Equinox. The back structure is different. As such, the Terrain is a little heavier, and it carries its own, unique calibrations.
AM: Talk to me about the D2XX platform in regards to the development of the Terrain?
MC: We needed to right-size this vehicle for the market. We looked at length. If we would have kept it the same as the outgoing vehicle, that's not the right move. It's a new GM. The new GM is about doing it right from the get-go. That brought along the all-new architecture from the ground up. This brought along some really cool things in terms of torsional stiffness. It means the vehicle is now rock solid, and we could really take advantage of the new mounting systems — powertrain mounts, ride and handling, etc. So, we now have a great ride and precise steering. The chassis isolates well but also manages head toss well.
Then there's fuel economy. We knew that if we designed the vehicle right, we could pull out mass. We pulled out 400 pounds. This helped with fuel economy, of course, but also improved powertrain responsiveness.
All of these goals caused great creativity with the engineers. We started with the 1.5-liter engine. But we knew that some GMC customers expect more and we must have a 2.0-liter. That engine is a little bigger (exterior dimensions). We had to package the larger engine in this smaller platform. The 2.0-liter engine was very, very challenging. We played with moving the fan one way, then having to move the catalytic converter another way.
AM: What have been some other specific challenges with the development of Terrain?
MC: Getting the platform right from a safety perspective, is one. Again, we wanted to pull mass out of the vehicle. The easy way, the convenient way to sort the safety requirements is to add mass back in. That's not creative engineering. It's one thing to pull out 400 pounds but I told engineering not to come back to me with proposals to add more metal here and there. We tortured ourselves as far as some very solid engineering. Necessity is the mother of invention. We did not relinquish the mass target, which was the necessity for creativity and invention.
The diesel was another. I'm very happy with that. Of course, we had to deal with the normal diesel NVH issues. We worked hard for a very refined integration, not just hitting the fuel economy goal. We call this diesel the Whisper Diesel inside GM. The guys in Torino (GM Powertrain Torino, Italy) did a very good job.
The EPS (electronic precision shift) was a challenge, too. It's new technology for us. Where do you put it, etc. That was the thing we spent a lot of time on. Michael Stapleton, our director for the Terrain interior, happened to be the single voice for EPS in the company. A beautiful thing, as it was an opportunity. We looked at going vertically or off to the side. We looked at the back of the console. It came down to getting rid of the shifter and maximizing that (center console) area.
AM: Both turbocharging and diesel are new for this vehicle at GMC. Was that all about emissions and fuel economy?
MC: Emissions is a given, and fuel economy is the price of entry. You can't just throw that out there and expect people to buy it. It was about excitement. I'll be honest and say that when we first started talking about the 1.5 [liter engine], I wasn't sure. The 2.0-liter and the diesel made sense, but a 1.5? But I clearly remember when I first drove the 1.5 at Milford [proving grounds in Michigan]. I called my boss right away and told him that it's a rock star. It's a rocket! I think most people will think they need the 2.0-liter, but once they get into the 1.5-liter — maybe a demo at the dealership — they'll be pleasantly surprised.
AM: What else did you want to change/improve on the outgoing Terrain?
MC: One of the big things is that there's no rear HVAC on the outgoing Terrain — for A/C. We have some very loyal customers, and we listened to them to make changes that matter the most. We've addressed those issues. It was also NVH and ride. Our customers are pretty happy now [with the outgoing Terrain], so it wasn't a matter a wholesale fix of all. The all-wheel drive disconnect is also new to Terrain, and unique to GMC. (The Terrain is the only GMC with this feature.)
AM: What vehicles did you benchmark with Terrain?
AM: What were the key test and development facilities for the Terrain?
MC: The main facilities were Milford and Yuma, Arizona. We did some diesel calibration in Europe — in Russelsheim [Germany] and Torino. Also, the active safety work at the new facility at Milford was a big plus. There is also a new dedicated active safety pad at Milford. This is for low-speed braking mitigation, lane keep assist, lane departure, forward collision alert, etc. — all new features for Terrain.