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Written by Bill Visnic
Almost bizarrely for a car brand and for a nation renowned for its predilection for large vehicles GM"s Cadillac is far behind its German premium-brand rivals in addressing the market"s endless thirst for crossover vehicles. It"s a model-development shortcoming that is hurting Cadillac in profits and customers. The luxury brand aims to make up for lost time by introducing the 2017 XT5, a midsize crossover that replaces the strong-selling but aged SRX. Perhaps equally important, XT5 is the first Cadillac crossover to use GM"s new "C1" global vehicle architecture that will underpin future larger and smaller Cadillac (and other GM-brand) crossovers. The next is the pending 2017 GMC Acadia. The C1 structure is utterly conventional in that it isn"t another Cadillac exemplar of mixed-materials design. Instead, its full-steel unitary structure was intricately modeled to produce big weight savings by optimizing the blending and joining of the platform"s disparate steel formulations (http://articles.sae.org/14679/). At about 3985 lb (1808 kg) in front--drive configuration and 4257 lb (1931 kg) with all-wheel drive, the new XT5 is up to 292 lb (132 kg) lighter than the SRX and demonstrably lighter than most rivals, even several that are significantly smaller. Superior dynamics, new V6 Weight- and strength-optimized structures are supposed to pay off in enhanced driving manners and dynamically, the XT5 at least when fitted with the optional adaptive damping and the AWD system"s sublime torque-vectoring effect palpably surpasses its like-sized competition, BMW X5, Mercedes GLE-Class and Lexus RX, leaving perhaps only the narrower-focus Porsche Cayenne and Jaguar F-Pace as midsize luxury crossovers with a more agility-oriented chassis tuning. On a MacPherson strut front and new-design 5-link independent rear suspension, the XT5 now blatantly sets the new ride/handling "balance" benchmark between the hard-cornering but heavy-feeling X5 and the roly-poly GLE and RX. The XT5"s electric power steering works with you and returns some sense of cornering-force buildup. But the best part is that while one never gets the sense of thumpy-stiff tuning just for the sake of mechanical grip, apart from the overtly sportier Cayenne and F-Pace, there isn"t a midsize crossover that seems as nimble or feels so comfortable in exercising its tire contact patches. Standard road wheel size is 18 in (305 mm); the upper trims bring 20-in (508-mm) wheels and the ZF-developed CDC4 adaptive suspension to govern them. Perhaps in a nod to the real and potential future complications that come from introducing an all-new platform, Cadillac is keeping the powertrain portfolio simple for now, serving up an all-new 3.6-L DOHC V6 and an Aisin-sourced TL80 8-speed planetary automatic transmission as the only propulsion combination. China-market versions of the XT5 will get a 2.0-L turbocharged 4-cylinder that very likely will have a future in North America, too. Although displacement is the same 3.6-L, the all-aluminum V6 is totally new and is being deployed throughout the GM firmament, with particularly good effect under hoods such as the 2017 Chevrolet Camaro. For the XT5, powertrain emphasis appears to be on optimizing fuel economy without a regression in power. This explains the proximity of its SAE-certified 310 hp and 270 lb ft (366 N m) metrics to the previous 3.6-L"s 308 hp and 265 lb ft (358 N m) ratings. Although the C1 platform locates the engine longitudinally (the outgoing SRX used a transverse engine), Cadillac did not use GM"s 8L45 8-speed automatic that backs this V6 in other longitudinal-engine models. Instead, engineers specified the Aisin gearbox that is also used in the Cadillac CTS. It includes a sport mode and can be paddle-shifted. The new V6 design brings upgrades such as full-authority phasing for all four camshafts, Active Fuel Management cylinder deactivation and a standard start-stop system that GM Propulsion engineers believe operates so discreetly that there"s no off switch. The system aggregate lighter weight, revised V6, two more transmission ratios bumps fuel efficiency by more than 8%. Front-drive models are expected to achieve 19 mpg (12.4 L/100 km) city and 27 mpg (8.7 L/100 km) highway, while AWD XT5s can deliver 18 mpg (13 L/100 km) city and 26 mpg (9 L/100 km) highway. "Twin-clutch" AWD The AWD layout also is all-new. Co-developed with GKN for this application, it utilizes a twin-clutch differential at the rear axle that imparts a torque-vectoring ability in addition to standard traction-enhancing qualities. The system can deliver 100% of available drive torque to either axle, with the slick twin-clutch differential able to apportion to either rear wheel as much as 100% of the torque it receives. Departing from the conventional "passive" drive strategy typically used for AWD crossovers in which the driver has no real options regarding the distribution of torque, Cadillac has elected to enable the driver to defeat AWD with the press of a button, leaving the XT5 to operate solely in front-drive mode regardless of road conditions. If AWD is engaged, however, then the system acts as automatically as most other AWD designs and remains in this mode until the defeat button is engaged. Larry Mihalko, XT5 vehicle performance manager, says that when in "automatic" AWD mode, some amount of tractive torque always is applied to each axle. Over-the-top luxury Rear-seat occupants are the biggest beneficiaries of the 2017 XT5"s 2 in (51 mm) of additional wheelbase, enjoying a newfound 3.2 in (81 mm) of legroom. (The XT5"s major exterior measurements all are nominally smaller than those of the SRX.) No passenger will feel slighted by the premium materials and satisfying textures that impart the requisite luxury cues without the excessive impression many luxury interiors currently impart. The leather dashboard inserts and look and feel of the microsuede headliner and trim are at the same time unique and understated, reinforcing the noticeable engineered quiet that comes from the acoustic windshield and advanced (but lighter-weight, of course) new sound-attenuation materials. The XT5 interior features Cadillac"s first use of a fully electronic shifter, which frees space below the console. During Automotive Engineering"s first drive of the vehicle, the new shifter presented a not-quite-perfected shift action. Engineers admitted the set-up was undergoing last-minute refinement surprising for a vehicle scheduled to reach showrooms in April. Other cabin highlights include the optional but marvelous rear-camera mirror (300% improved rear field of vision compared with the conventional rearview mirror) and a head-up display. There"s also the expected raft of driving-assist systems such as lane-keeping assist, automatic front and rear low-speed braking, auto collision braking and automatic parking and full-range adaptive cruise control. The 2017 Cadillac XT5 comes in four basic trim levels, from base to Premium, with AWD available on all but the base model. The vehicle is assembled at GM"s newly refitted Spring Hill, TN, complex which also will produce the C1-derived GMC Acadia. The China-market XT5 will be built at GM"s new plant in Pudong, near Shanghai.
Date written: 18-Mar-2016 12:33 EDT
More of this article on the SAE International Website
ID: 2615
Almost bizarrely for a car brand and for a nation renowned for its predilection for large vehicles GM"s Cadillac is far behind its German premium-brand rivals in addressing the market"s endless thirst for crossover vehicles. It"s a model-development shortcoming that is hurting Cadillac in profits and customers. The luxury brand aims to make up for lost time by introducing the 2017 XT5, a midsize crossover that replaces the strong-selling but aged SRX. Perhaps equally important, XT5 is the first Cadillac crossover to use GM"s new "C1" global vehicle architecture that will underpin future larger and smaller Cadillac (and other GM-brand) crossovers. The next is the pending 2017 GMC Acadia. The C1 structure is utterly conventional in that it isn"t another Cadillac exemplar of mixed-materials design. Instead, its full-steel unitary structure was intricately modeled to produce big weight savings by optimizing the blending and joining of the platform"s disparate steel formulations (http://articles.sae.org/14679/). At about 3985 lb (1808 kg) in front--drive configuration and 4257 lb (1931 kg) with all-wheel drive, the new XT5 is up to 292 lb (132 kg) lighter than the SRX and demonstrably lighter than most rivals, even several that are significantly smaller. Superior dynamics, new V6 Weight- and strength-optimized structures are supposed to pay off in enhanced driving manners and dynamically, the XT5 at least when fitted with the optional adaptive damping and the AWD system"s sublime torque-vectoring effect palpably surpasses its like-sized competition, BMW X5, Mercedes GLE-Class and Lexus RX, leaving perhaps only the narrower-focus Porsche Cayenne and Jaguar F-Pace as midsize luxury crossovers with a more agility-oriented chassis tuning. On a MacPherson strut front and new-design 5-link independent rear suspension, the XT5 now blatantly sets the new ride/handling "balance" benchmark between the hard-cornering but heavy-feeling X5 and the roly-poly GLE and RX. The XT5"s electric power steering works with you and returns some sense of cornering-force buildup. But the best part is that while one never gets the sense of thumpy-stiff tuning just for the sake of mechanical grip, apart from the overtly sportier Cayenne and F-Pace, there isn"t a midsize crossover that seems as nimble or feels so comfortable in exercising its tire contact patches. Standard road wheel size is 18 in (305 mm); the upper trims bring 20-in (508-mm) wheels and the ZF-developed CDC4 adaptive suspension to govern them. Perhaps in a nod to the real and potential future complications that come from introducing an all-new platform, Cadillac is keeping the powertrain portfolio simple for now, serving up an all-new 3.6-L DOHC V6 and an Aisin-sourced TL80 8-speed planetary automatic transmission as the only propulsion combination. China-market versions of the XT5 will get a 2.0-L turbocharged 4-cylinder that very likely will have a future in North America, too. Although displacement is the same 3.6-L, the all-aluminum V6 is totally new and is being deployed throughout the GM firmament, with particularly good effect under hoods such as the 2017 Chevrolet Camaro. For the XT5, powertrain emphasis appears to be on optimizing fuel economy without a regression in power. This explains the proximity of its SAE-certified 310 hp and 270 lb ft (366 N m) metrics to the previous 3.6-L"s 308 hp and 265 lb ft (358 N m) ratings. Although the C1 platform locates the engine longitudinally (the outgoing SRX used a transverse engine), Cadillac did not use GM"s 8L45 8-speed automatic that backs this V6 in other longitudinal-engine models. Instead, engineers specified the Aisin gearbox that is also used in the Cadillac CTS. It includes a sport mode and can be paddle-shifted. The new V6 design brings upgrades such as full-authority phasing for all four camshafts, Active Fuel Management cylinder deactivation and a standard start-stop system that GM Propulsion engineers believe operates so discreetly that there"s no off switch. The system aggregate lighter weight, revised V6, two more transmission ratios bumps fuel efficiency by more than 8%. Front-drive models are expected to achieve 19 mpg (12.4 L/100 km) city and 27 mpg (8.7 L/100 km) highway, while AWD XT5s can deliver 18 mpg (13 L/100 km) city and 26 mpg (9 L/100 km) highway. "Twin-clutch" AWD The AWD layout also is all-new. Co-developed with GKN for this application, it utilizes a twin-clutch differential at the rear axle that imparts a torque-vectoring ability in addition to standard traction-enhancing qualities. The system can deliver 100% of available drive torque to either axle, with the slick twin-clutch differential able to apportion to either rear wheel as much as 100% of the torque it receives. Departing from the conventional "passive" drive strategy typically used for AWD crossovers in which the driver has no real options regarding the distribution of torque, Cadillac has elected to enable the driver to defeat AWD with the press of a button, leaving the XT5 to operate solely in front-drive mode regardless of road conditions. If AWD is engaged, however, then the system acts as automatically as most other AWD designs and remains in this mode until the defeat button is engaged. Larry Mihalko, XT5 vehicle performance manager, says that when in "automatic" AWD mode, some amount of tractive torque always is applied to each axle. Over-the-top luxury Rear-seat occupants are the biggest beneficiaries of the 2017 XT5"s 2 in (51 mm) of additional wheelbase, enjoying a newfound 3.2 in (81 mm) of legroom. (The XT5"s major exterior measurements all are nominally smaller than those of the SRX.) No passenger will feel slighted by the premium materials and satisfying textures that impart the requisite luxury cues without the excessive impression many luxury interiors currently impart. The leather dashboard inserts and look and feel of the microsuede headliner and trim are at the same time unique and understated, reinforcing the noticeable engineered quiet that comes from the acoustic windshield and advanced (but lighter-weight, of course) new sound-attenuation materials. The XT5 interior features Cadillac"s first use of a fully electronic shifter, which frees space below the console. During Automotive Engineering"s first drive of the vehicle, the new shifter presented a not-quite-perfected shift action. Engineers admitted the set-up was undergoing last-minute refinement surprising for a vehicle scheduled to reach showrooms in April. Other cabin highlights include the optional but marvelous rear-camera mirror (300% improved rear field of vision compared with the conventional rearview mirror) and a head-up display. There"s also the expected raft of driving-assist systems such as lane-keeping assist, automatic front and rear low-speed braking, auto collision braking and automatic parking and full-range adaptive cruise control. The 2017 Cadillac XT5 comes in four basic trim levels, from base to Premium, with AWD available on all but the base model. The vehicle is assembled at GM"s newly refitted Spring Hill, TN, complex which also will produce the C1-derived GMC Acadia. The China-market XT5 will be built at GM"s new plant in Pudong, near Shanghai.
Date written: 18-Mar-2016 12:33 EDT
More of this article on the SAE International Website
ID: 2615
