Wednesday, September 3, 2008

Dodge hopes smooth ride of coil springs will distinguish Ram

Dodge uses a coil spring suspension on the 2009 Ram pickup.
When the 2009 Dodge Ram 1500 reaches dealerships this month, it will be the only full-sized pickup offering a five-link, coil spring rear suspension.

In a segment where cherished traditions really matter, why take a chance doing something nobody else is doing?

By talking with its customers, particularly those trying pickups for the first time, Dodge learned they were not enamored of the bouncy, jittery ride that comes with traditional elliptical leaf-spring rear suspensions, which descend directly from the horse and buggy. Dodge will continue to use leaf springs in heavy-duty versions of the Ram.

Although carmakers have switched to link and coil spring arrangements on the rear suspensions of full-sized, body-on-frame SUVs, they've stuck with leaf springs on pickups. Leaf springs have an aura of toughness, and they've proved themselves over generations in pickups, where users care more about payload and towing capacity than a silky ride.

But Dodge thinks it has engineered a system that will handle tough loads and improve ride quality.

"There was clearly a demand for better ride," Scott Kunselman, Chrysler LLC vice president of truck product development, said last month at the Ram media introduction.

Now Dodge must convince pickup customers that the new rear suspension is as tough and durable as leaf-spring rear suspensions. Dodge should find early road tests encouraging.

"The new Ram delivers ride and handling that are the current best of breed," wrote NextAutos.com, a road test Web site. "The big Ram doesn't bob or weave or toss your head about over rough pavement, and the interior remains surprisingly quiet regardless of the road surface — or lack of road surface."


Taking a beating
Dodge won't disclose its advertising strategy for the truck until October, but look for the ads to point out what Dodge engineers have been saying: Coil springs work just fine in other heavy-duty applications such as rail cars and semitrucks.

Kunselman said Dodge has no concerns about the durability of the rear suspension.

The problem with leaf springs is they must do too many jobs, he said. Those jobs include not only suspending the truck but also positioning the solid rear axle, Kunselman said.

In the Dodge coil spring setup, the links connect the solid rear axle to the frame, leaving the springs free to do just one job — springing the load.

Don Sherman, technical editor for Automobile magazine, said that, despite their ruggedness, leaf springs have several drawbacks. One is weight. Dodge cut 40 pounds from the Ram by switching to rear coil springs.

"Also, they're bulky," Sherman said. "A big problem is friction. You don't want friction in the suspension. (Friction) tends to cause a harsher ride."


Dodge 'mavericks'
Sherman also said Dodge is once again doing what it did in the early 1990s with styling.

"What they're looking for is some way to distinguish themselves from the herd," he said. "That was the Ram story all the way back. They made it look like a Peterbilt. It was something different."

Marc Seguin, launch manager of the 2009 Ram 1500 pickup, put it another way: "We don't follow. We lead. We like to think of ourselves as mavericks."

Now Dodge will wait to see whether competitors--and customers--follow.

No comments: