The former Bosch, Bendix and Studebaker proving grounds near New Carlisle in northern Indiana is open for business under new ownership: Navistar Inc., which took it over as of April 1.

The company showed off the facility to industry reporters Tuesday with a multi-vehicle ride-and-drive that covered many of the on- and off-road testing paths on the sprawling 668-acre site.

Its main feature is a 3-mile paved and banked oval that allows steady 65- to 70-mph cruising by heavy tractor-trailers, something Navistar engineers never had before, executives said. The facility is replacing Navistar’s old technical center in Fort Wayne, a much smaller property that is being sold.

The New Carlisle proving grounds also include shops and equipment that allow extensive testing and maintenance of the wide variety of trucks and buses that Navistar builds. Navistar bought the facility from Robert Bosch, the German component maker that had acquired it from Bendix Corp. in the 1990s.

“Bosch didn’t use it anymore,” said Dennis Mooney, vice president for global product development. “We were really lucky. We got it for a really good price,” though he declined to say what it was.

“This falls in with our emphasis on uptime,” he said. “We’ll use it to make our trucks even more reliable.”

Executives and technicians showed off 14 International heavy trucks and tractors and four medium-duty models and allowed reporters to drive them on the long track, across rough testing surfaces and off-road courses. These were samples of the type of rigorous testing that the company can now do on its own property instead of renting time at other firms’ facilities.

Previous owners rented various parts of the premises to other companies for testing and Navistar intends to continue that practice. In a typical year, 50 different suppliers and truck builder conduct testing, said Steve Nash, director of operations who works out of Navistar’s engine and engineering center at Melrose Park, west of Chicago.

One current tenant is Daimler Trucks North America, which uses a large shop and the various tracks to test Freightliners. Daimler has two years left on its Bosch contract and is welcome to stay at New Carlisle, Nash said.

The proving grounds are about a 90-minute drive from Navistar’s headquarters in Lisle and Melrose Park, so the facility is convenient to engineers and executives there, Nash said. Fort Wayne is another 90 minutes to the southeast, and was not easy for Chicago-area people to get to.

In addition to the high-speed paved track and off-road courses, the proving grounds also include:

• Brake testing capabilities which include infrastructure, complete instrumentation and computerized data acquisition;

• Structural durability testing and accelerated-mile accumulation with road profile capability using accelerometer and strain gage data and multiple road surfaces including chatter, impact, cobblestone, undulating, resonance road surfaces, gravel, body/chassis twist event and off- road surfaces; and

• Specialized testing such as vehicle noise and handling, center-of-gravity, rollover and roof crush testing, grade-ability up to 60%, traction control, powertrain durability among others.

“The new Navistar Proving Grounds is a strategic addition to our product development operations and will play an important role in our mission to deliver industry-leading uptime for our customers,” said Bill Kozek, president, Navistar Truck and Parts, in a statement. “Beyond testing our latest vehicles and innovative technologies, we will also use the site as a customer center to showcase new products and give customers an opportunity to experience our vehicles firsthand.”