Silent Partners make good neighbours: you can lose a whole lot of public good will with one driver and some ill-timed air brake use [Noise suppression equipment]

It's near midnight at the edge of town. One of your drivers, fully loaded and rolling into town, makes the mistake of using his air brake. Everyone he disturbed knows whose truck it is -- after all, who else hauls into town at this hour-and they're not happy about it.

Despite driver education, this scenario happens more than it should. But now there's something you can do about it. A fleet manager for a mass merchandiser is using Donaldson's new Silent Partner to help improve the image of his company, his fleet and the trucking industry.

It makes us a good neighbour and a good partner on the road. That's what Herman Miller says about the new Donaldson Silent Partner silencer. As one of the first to operate Silent Partner-equipped vehicles on a day-to-day basis, his experience offers a valuable insight into the real world behaviour and benefits of this new approach to vehicle noise control.

For Miller, the issue of vehicle noise in general -- and engine brake noise in particular -- is important on several levels. The first, and one that the forest industry is most sensitive to, is image. "The name of our store is in 30-foot letters along the side of our trailers," Miller points out. "So everything our trucks do affects the image of our store with people who are potential customers. That's why being a good neighbour on the road really matters to us." But it's difficult to be a good neighbour when conditions force your rigs to make loud, harsh engine braking noises. As Miller explains, "When you're going through a little mountain town at 3 o'clock on a still, clear night, putting on the Jake Brake can rattle windows miles away. That's not the sort of thing you want people to associate with your name when you're a mass merchandiser."

Nor when you're trying to garner public support for your local logging or sawmilling operation.

Safety also a factor

Engine braking noise control is important to Miller for another reason, one that has to do with keeping operations as safe as possible. His fleet travels an area that stretches from Lake Michigan to the Pacific Ocean, and from the Canadian border down to 1-80. This territory encompasses some of the most mountainous routes in North America, roads where the greater control and safety of engine brakes are critical. Miller says that, "with the weight limits we run, there are times when we need and want more brake than we get from the service units." In fact, Miller instructs his drivers to rely solely on engine brakes whenever possible on downgrades, so that the vehicle's regular service brakes will be at full effectiveness if needed in an emergency. Any technology that can minimize engine-braking noise will allow drivers to use engine brakes more frequently. And that translates into greater safety for everyone on the road.

So when Miller first heard about the Donaldson Silent Partner silencer last summer -- from a Detroit Diesel engineer at a meeting -- he was intrigued. "I didn't know there was anything on the market that would really reduce Jake Brake noise," he says. "But any time you can do something for noise abatement at a reasonable cost, it's worthwhile to consider.

Miller agreed to try out Silent Partners on three of his trucks. The first thing that impressed him was Silent Partner's bolt-on interchangeability with conventional mufflers. As he recalls, "They were exactly like the mufflers we replaced. The only difference was the part number -- and the performance."

As for Silent Partner's performance, Miller reports, "We were pleasantly surprised. Silent Partner did everything I was told it would do. It really gets rid of that harsh sharpness with Jake Brakes. We didn't see any backpressure increase, so we didn't lose any power. In fact, backpressure might actually be less with the Silent Partner."

Miller's drivers were equally impressed. "They're as image-conscious as I am. They like the fact that heads don't turn in town anymore when they hit their Jake Brakes." He sums up his experience with Silent Partner succinctly: "I'm satisfied, the drivers are satisfied." And as a result, Miller is specifying Donaldson Silent Partner silencers as OEM equipment for the five new Freightliner Argosy cabovers his fleet has on order.

Herman Miller sees Silent Partner as having potential impact far beyond his fleet. "The only reason there are laws against Jake Brakes is because of the harsh noise. If you can get rid of the noise, you can get rid of the laws." He continues, "Image is crucially important to the trucking industry, especially an operation like ours. We deal directly with our store's customers, who are on the roads and in the towns we drive through. Silent Partner lets us become better citizens and neighbours with everyone -- at a reasonable cost. There are a lot of issues and problems facing the trucking industry today. Noise is just one part of it -- but it's a part we can easily fix."