General Motors threw many industry analysts and media pundits an unexpected knuckleball when it unveiled the next-generation Cadillac SRX crossover utility at a pre-NAIAS backgrounder. The 2010 SRX is a smaller, sleeker, and more efficient overall package than its predecessor, which was based on the CTS sedan’s rear-drive Sigma architecture.
But the surprise came in learning the five-seat ’10 SRX is not based entirely on the Theta architecture, which underpins the Saturn Vue and 2010 Chevrolet Equinox, as had been widely expected. Rather, the new midsize Cadillac (which was originally slated for the BRX nameplate) uses an all-new architecture internally known as TE. It incorporates some Theta structural geometries as well as elements of the Global Epsilon D-segment sedan architecture.
“Our primary development bogey was the Lexus RX350, which has been the segment leader,” Chief Engineer Lyndon Schneider told AEI. “In terms of driving dynamics, we heavily benchmarked the BMW X3.” He explained benefits of the new TE architecture include front-drive for base models, with AWD optional, as well as the future potential to offer GM’s Two-Mode hybrid system—“there’s no reason it wouldn’t package on SRX,” he noted.
The all-wheel-drive version uses a Haldex differential with electronically controlled limited-slip differential (eLSD) to distribute drive torque based on individual wheel grip and stability-control system inputs. (The system interacts with StabiliTrak but has its own controller, said Schneider.) GM uses a similar setup on Saab’s Turbo-X. The Haldex unit can vector up to 100% of available torque front-to-rear or side-to-side, depending on where traction is needed in a given driving situation.
GM Powertrain’s European technology shelves also provide the new SRX’s premium engine option—a turbocharged 2.8-L V6 rated at 300 hp (223 kW) and 295 lb·ft (396 N·m). It’s the first turbocharged engine ever offered in a North American market Cadillac, according to the company, and is mated with an AF40 six-speed automatic supplied by AisinWarner.
SRX’s new direct-injected 3.0-L V6 base engine replaces the old SRX’s port-injected 3.6-L V6 and offers similar power with greater fuel efficiency. It’s a slightly more powerful version of the new LF1 used in the 2010 Chevrolet Equinox and other GM vehicles. In SRX, it’s rated at 260 hp (194 kW), up 5 hp (4 kW) over the Equinox, with the same 221 lb·ft (300 N·m) torque rating. The engine is calibrated for 87-octane regular fuel, and its Hitachi-supplied injection system is E85-capable.
The 3.0-L is mated to a 6T70 Hydra-matic six-speed, with a control strategy offering a driver-selectable “eco mode” algorithm that alters shift points to maximize fuel economy. For front-drive models, Schneider expects an EPA highway fuel economy rating in the mid-20-mpg range when testing is complete.
Theta genetics contribute a 190.2 in (4833 mm) overall length and 110.5-in (2807-mm) wheelbase, slightly altered from SRX's Equinox half-cousin. Front and rear track are relatively wide at 64.0 and 63.7 in (1626 and 1620 mm), respectively, with standard 18-in and optional 20-in road wheels. Even with its aluminum suspension control arms, SRX is no flyweight; curb weight of the base front-drive variant is 4300 lb (1950 kg), and all-wheel drive adds about 165 lb (75 kg). The vehicle’s maximum towing rating is up to 3500 lb (1587 kg).
SRX’s body stiffness has been improved from the previous version; Schneider notes that first-order bending and torsion are 27 and 31 Hz, respectively. Martensitic steel is used in the vehicle’s fully boxed rockers, which Schneider said helps reduce side-impact intrusion while maintaining the structure during front and rear impacts. SRX was also designed to meet European pedestrian protection standards; its front bumper is positioned for greater compatibility with car bumpers.
Improving structural rigidity allowed engineers to more precisely calibrate the strut-based front suspension and multilink rear layout, with their real-time-controlled variable-rate dampers. The remote-controllable power rear liftgate incorporates an adjustable height setting.
Inside the 129.8 ft³ (3676 L) SRX cabin, drivers are greeted with a pop-up navigation screen with three-dimensional imaging. Bluetooth compatibility is standard, as is turn-by-turn OnStar navi service for buyers who do not select the car’s navigation package option. SRX’s safety equipment includes optional adaptive forward lighting that swivels the headlamps in sync with vehicle steering.
Start of production is slated for second-quarter '09 at GM’s Ramos Arizpe, Mexico, assembly plant.