Truck arms, which are based on 1960s technology, stood the test of time in NASCAR. But, as NASCAR evolves into a new generation of cars and a revamped schedule, the truck arms may not be necessary. You may ask whether NASCAR uses truck arms on their Next Gen cars.
While NASCAR used truck arms for decades, they do not use them on the Next Gen car. Instead, NASCAR opted to use a rear suspension and transaxle unit that gave the new designs a sports car appeal. The new suspensions also specialize in the cars turning both left and right.
Below, we will outline what truck arms were on NASCAR’s older generations. We will also discuss the new rear suspension and transaxle units, what they mean for NASCAR’s future, and how the sportier car designs may return interest to a sport that has been seeing declining viewership.
What Are Truck Arms On A Racecar?
Truck arms on a car? That doesn’t sound right, does it? But in NASCAR, it is completely normal for truck arms to go onto a car. At least as far as the previous generations are concerned. You may also have heard that NASCAR, even throughout 4 different generations of cars in the 21st century, loves to keep some technological aspects as is. And truck arms were one of them.
If NASCAR sought new technologies, they have historically been slow to develop them. For example, they didn’t introduce fuel injection to the Cup Series until 2012. Something that never quite made it to the Xfinity and Truck Series, which still used carburetors.
They also never bothered to upgrade the steering box until they introduced the Next Gen. You can trace the old recirculating ball steering box to NASCAR’s early days. So given the eons-old technology, it makes sense they used truck arms even into the Generation 6 car’s life span from 2013 to 2021.
Truck Arms Explained
Truck arms resembled something you would have seen on a 1960’s model Chevrolet truck, hence the name truck arms. They were two, 51-inch trailing arms and two additional I-beams that formed an irregular trapezoid-like shape on the axles.
You would find them bolted into the car’s front and rear end. They also had a track bar to complete the rear suspension. This bolted to the truck arm’s left, on the right-hand side of the chassis.
The truck arms, like the engines and bodies, were also held to NASCAR’s specifications. For example, in 2017, NASCAR fined Todd Gordon of Joey Logano’s team $50,000 and suspended him for two weeks because of a 1/32-inch gap on the right-side truck arm when NASCAR mandated full contact at all times.
Problem was, these could come loose during a race at no fault to the crew. Which was the case that Gordon argued. Nevertheless, Gordon ended up missing the next two races. But NASCAR was hard at work planning for its next car design.
Does The Next Gen NASCAR Car Use Truck Arms?
The Next Gen NASCAR also does not use truck arms. While NASCAR’s track record with upgrading technology can be spotty, they deemed it necessary to get rid of the old chassis and truck arms. The Next Gen car features an independent rear suspension, giving it a sportier design.
One major drawback with the older truck arms is that teams could not adjust them as thoroughly, prompting NASCAR to make the change to an independent suspension. This helps teams on road courses, which NASCAR added more to the schedule in 2021. The road course trend continued in 2022.
To the untrained eye, the Next Gen NASCAR car may look just like the Generation 6. But anyone who follows NASCAR even remotely will discover a lot of key differences between the Next Gen and its predecessor. The engines also have different horsepower packages, the transmission is a manual 5-speed sequential, and the wheels look more like what you would find on a showroom car.
The biggest difference is the fact the cars look more like street-legal Chevrolet Camaros, Ford Mustangs, and Toyota Camrys.
How Does The Rear Suspension Work On The Next Gen Car?
NASCAR catapulted into the 21st century with the advent of the Next Gen car. But since lifelong fans had grown used to similar car components for the last few decades, NASCAR also needed to go into great detail on how these nifty Next Gen cars worked. Before they hit the road course at Circuit of the Americas (COTA), NASCAR broke down the rear suspension’s ins and outs.
Why did NASCAR wait so long to truly spotlight the new rear suspension? Because COTA was the first road course race to use it. And since NASCAR redesigned the rear suspension with road courses in mind, they wanted to show the fan base their epic creation.
Before NASCAR came to COTA, drivers who tested it described the rear suspension as being more nimble, with quicker acceleration, turning, and stopping. It was more receptive to sudden changes, and it was shiftier than the older generation’s suspension.
The Old Rear Suspension Design
On the old suspension, the truck arm was attached to the rear axle. They had no pivot point. Teams also put springs between the arms and chassis, and in front of the axle tube. Besides the truck arms resembling something from an old Chevy truck, sources also compared this look to an N95 Mustang.
This suspension was not road course friendly. So when NASCAR added more road courses to their schedule in 2021, they realized they needed to make sure their cars could turn both left and right.
And since NASCAR is further looking to reinvigorate lost interest in the sport, they also contemplated adding a street race to the schedule. And if you watched street races in the competing IndyCar Series, NASCAR cars would also need to specialize in turning right and left often.
How The Next Gen Rear Suspension Works
The independent suspension contains dual A-arms that teams can use on either side of the chassis. This also comes with a coilover suspension, and a transaxle replaced the rear live axle from the previous generations of cars.
This combined the differential housing and the transmission, which compared to front-engine, rear-wheel drive sports cars like the C7 Corvette. Gone was the old steering, and NASCAR replaced it with a rack-and-pinion design.
Further, the transmission has also been overhauled. The older cars used a 4-speed transmission and an H-pattern gearbox. The Next Gen cars have gone with a 5-speed, sequential manual which makes it easier for drivers to shift up and down by moving the gearshift one notch.
Is NASCAR Transformed?
Motor Biscuit believes the new independent rear suspension setup and Corvette-style transaxle will further transform NASCAR from an old-fashioned sideshow whose fan base left it for greener pastures into something revolutionary. Whether it will bring back old fans remains to be seen.
But NASCAR has realized, with the new suspension and sports car-style aesthetics the Next Gen brings, they can also accommodate a new generation of fans. So what makes this new transaxle more exciting? For one, it is nowhere near as front-heavy, giving it better handling than the old cars.
While sports car engineers had been combining the transaxle units for nearly a century, NASCAR never got the memo. It started with Bugatti in the late 1920s before Lancia adopted the method in the 1950s, followed by Ferrari in the 1960s, and finally, Alfa Romeo a decade later.
Finally, the Chevy Corvette followed suit in 1997 and 25 years later, NASCAR came around. So has NASCAR officially been transformed into a sports car-stock car organization? The exterior and the interior aesthetics are there, so that may be the case.
What The Suspension Means For NASCAR’s Future
For NASCAR, the future is now with more road courses on the schedule. But with the new rear suspension and transaxle, this could possibly mean even more road courses. Whether they come on the streets of Chicago or on a closed circuit, NASCAR may be in line to sacrifice a few more ovals.
Or, they can race infield. Pocono is one track that has a road course in the infield. And NASCAR has already raced at the Charlotte Roval, Indianapolis Motor Speedway’s road course configuration, and the Daytona road course.
While you will probably never see NASCAR’s historic ovals like Daytona, Bristol, Talladega, Darlington, Charlotte, Martinsville, and Atlanta fall to the wayside, you may see NASCAR do away with others. Especially if their independent suspension on the road courses works as advertised.
NASCAR has seen declining ratings for years now. And they took the first step in turning the tide with the advent of the Next Gen car, purging the ancient truck arms and all that ancient technology that belongs in a museum somewhere.
NASCAR used truck arms for decades before the advent of the Next Gen car. One reason NASCAR did away with the truck arms came from the addition of more road courses. This necessitated a change in the rear suspension to make it more road course friendly.
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