Arizona attracts car lovers looking to get away from damaging road salt used in cold weather. The desert conditions also bring major automobile companies to test their brand new cars. 

In a test track east of Maricopa, drivers ride on different types of road conditions one probably tries to avoid – patchy asphalt, uneven brick roads and a whole stretch of potholes.

Here at Nissan’s only American proving grounds, those drivers ride over this terrain for hours on end – on purpose.

(Photo by Casey Kuhn - KJZZ)

A 2018 Ford Expedition being tested in Arizona Proving Grounds.

“One mile on this course is many miles of a customer driving,” said Derek Logan, manager at the proving grounds.

The grounds are like a giant obstacle course with dozens of different "events," like curbs to run into and even a small jump.

Logan has worked on the durability testing, as well as the long oval track where cars have been known to go more than 200 miles-an-hour once. Logan's bulky white van doesn’t quite make it to that speed.

“So let’s go ahead and accelerate up to at least 90 so we can get in that lane,” Logan said, driving the van into the outermost lane. That lane is on a steep angle and has a speed minimum of 90 mph.

Logan is also a long-time member of the Society of Automotive Engineers (SAE), which develops car standards. That could be anything from a bolt to a test of how a car performs.

Those kinds of tests are used at each proving ground, including the 1,500 acre Arizona Proving Grounds (APG) in Wittmann, where Ford tests new cars for market.

(Photo by Casey Kuhn - KJZZ)

A car being heat-tested at the Arizona Proving Grounds.

There, a black sedan sits in the sun, covered in yellow and orange wires that look like electrodes.

“Each one of these yellow wires ends in a temperature measurement," said Robbie Schaffer, APG test technician. "We have hundreds of these all over the vehicle.”

Schaffer said the test measures how temperatures up to 125 degrees affect a car’s interior and exterior. A kind of test made for the desert.

“And it’s consistently hot," Shaffer said. "We’ve got more months with hot weather throughout the year than any place else in North America.”

While heat and fair weather are the main draw, auto companies also come to Arizona because it’s near Colorado River’s Davis Dam, a long incline used to test tow strength.

APG Supervisor Butch Finkbeiner said simulating thousands of pounds of towing force on a hill can help a car maker figure out how to stop an engine overheating.

“The company may decide 'OK I’m going to reduce the amount of time the A/C is cycling because that’s drawing down the engine cooling capabilities,'” he said.

And, Death Valley - one of the hottest places in the world - isn’t too far away either.

Finkbeiner said these tests help spot problem areas. For example, a chrome gear shift that gets too hot to handle in the sun.

“Typically what they’re exposed to, what the customers put their vehicles through, that’s how we’re testing to ensure that, once they’re out there in the public, they’re going to meet their needs,” Finkbeiner said.

Proving Grounds Need Two Things: Secrecy And Consistency

Back at Nissan’s proving ground, cars with black and white camouflage line the parking lots. The camo is to fool photographers hoping to get a glimpse of a car before it’s released. There are also high berms surrounding the track to keep travelers from seeing the cars.

Logan said the point is to create an environment that is consistent and also re-creatable.

To show the ground’s versatility, he drives up a track that winds like a road in California.     

“So this is San Gabriel, this is one of the more fun parts of the course,” Logan said, as the engine revved.

(Photo by Casey Kuhn - KJZZ)

A machine that simulates thousands of pounds of towing on an incline.

He guided the van up, wrenching the steering wheel at each quick turn.

“And then coming up here on the left we have Allen road, in Michigan,” he said.

Michigan proves to be bumpier, with broken concrete. 

“So here let’s go to Massachusetts, let’s get onto Route 12,” Logan said, rounding another bend to a different road.

And another key aspect they test here is the sound of the car.

“Something might be really good for handling but it might create more noise, so we have to create that balance,” he said.

Microphones stuck to cars and on the side of the track test volume.

But, Logan said car engines are getting quieter, leading to new problems like more wind noise.

And, cars are getting smarter. He said the proving grounds should have staying power, even as autonomous vehicles are testing in the Valley streets.

“But there’s still some physical testing that is imperative, that still has to be done," Logan said. "There’s too many variables out there to predict the environment, the corrosion, the rough road. There's also some testing we do that's subjective analysis, that's just kind of a feel.”

If there’s still someone in the car, car-makers have to keep that human experience in testing, whether they’re driving or not.