Nissan Targets Cabin NVH, Makes Big Investment in Sentra Upgrade

April 11, 2016

Kami Buchholz

To go along with its new design language influenced by the larger Altima and Maxima, the 2016 Sentra gets a quieter cabin and much livelier driving dynamics.

Significant updates to the seventh generation Sentra make the 2016 model Nissan’s quietest and most dynamic-driving compact sedan to date. The automaker invested more than three times its typical outlay for a mid-cycle refresh on Sentra, according to Chris Schwerkoske, a senior product planner.

The 2016 model contains more than 550 new parts involving the exterior, interior, suspension, and steering systems, Schwerkoske told Automotive Engineering.

With the Sentra revamp, Nissan aims "to remain a leader in the highly competitive compact car segment,” said Robert Mank, an engineer with Nissan Technical Center North America’s Marketability Engineering group.

The 2016 Sentra's interior features a new Nissan Z-inspired steering wheel, new advanced 5-in drive assist display, available 6-way power driver's seat with two-way power lumbar support, new shift knob, and more.

He said the current generation Sentra was fully redesigned in 2013MY. Since that time, compact sedan makeovers have included full redesigns of the Mazda3 and Toyota Corolla in 2014MY, as well as the 2016MY debut of the 10th-generation Honda Civic.

Sentra's cabin noise was reduced through various changes, including replacing the prior non-laminated windshield with an acoustic windshield, and adding sound-reduction materials under the dash, inside the door trim, and underneath the floor carpet.

Explained Mank, “In specific cabin areas, material was added where there was no sound absorption material before, and in other areas we replaced material that wasn’t as high-performance as the Autozorb material.” Supplied by AIM Fiber Products, Autozorb is a lightweight, 100% polypropylene fibrous insulation blanket designed to provide interior acoustical and thermal protection.

Engine mounting changes contribute to the approximately 10% reduction in the new Sentra's engine noise, noted Mank. “The upper torque rod was removed to change the noise path of the engine," he said, "and lateral rubber stoppers were added to one of the lower engine mounts to compensate for the upper torque rod function.”

Software updates to the Xtronic continuously-variable transmission (CVT) also impede powertrain noise from reaching the cabin.

“Instead of the engine holding high rpm—which means more engine noise—the CVT now varies the rpm and delivers variable engine noise in a more linear way," Mank said. "Engine noise now more closely matches engine demand, which is similar to a standard-step automatic transmission.”

The 2016 Sentra shares design language with the midsize Altima and fullsize Maxima. That look is conveyed via Sentra’s new hood, fenders, grille, front and rear fascias, headlamps, tail lamps and wheel designs.

Suspension changes include 10% higher spring rates, re-tuned front struts and rear shocks, and stiffer rear bushings. The prior one-piece stamped steel front tunnel bracket was replaced with a four-piece boxed-type front tunnel bracket (initially developed for the Nissan Juke NISMO RS) to increase the body stiffness. According to Schwerkoske, “The 2016 car responds more quickly to driver inputs.”

Other changes impacting Sentra’s driving dynamics include new electric power steering controller mapping, a new steering column intermediate shaft with higher torsional stiffness than the predecessor, and new Continental 16-in tires for the SV trim. The new tires have a higher grip tread compound and increased sidewall stiffness compared to the prior 16-in Continentals.

“The overall goal with the suspension and steering changes was to enhance the ride comfort and the handling,” said Schwerkoske. The 2016 car has a more progressive steering feel, while steering effort has been reduced by 7%, which helps improve how the car behaves during parking maneuvers and other low-speed driving.

For the first time, Sentra is available with forward emergency braking, intelligent cruise control, and radar-based blind spot warning with rear cross traffic alert. Said Schwerkoske, “We’re bringing some of the premium driver assistance technologies that we launched with the Maxima to the Nissan Sentra."