Why do ambulances have chains hanging underneath

The Onspot Automatic Tire Chain System offers the traction of a single set of conventional snow chains at the flip of the dashboard switch without having to stop the vehicle. Onspot works when accelerating in forward or reverse or when braking in either direction. Two reasons. The Liquid Tire Chain theory was sound. Inside the canisters was a space-age polymer ready to coat the rear tires and turn slip into grip. Press the button and presto!

Evaporating solvent left a traction-improving chemical compound on the tires that resulted in instant winter traction, even on ice. The chains are designed to provide traction on snow-packed and icy roads and struggle to function in thick snow, Snoozy said. They can also become frozen inside the bus if there is snow and ice blowing around on the roads. A pilot program in North Carolina in the early s tested the theory that a school bus with a white roof would make for a cooler experience for the passengers.

The results were profound. The program found white-topped buses had internal temperatures an average of 10 degrees cooler than yellow-topped buses. Driving too fast with chains. Each chainwheel has 6 lengths of chain attached to it. The centrifugal force created causes the chains to flail out and pass between the tire and road surface to enhance traction in snow and ice in forward or reverse. Liquid Tire Chain: Activate a control on the instrument panel and a traction-increasing fluid is sprayed on the rear tires to provide greatly improved traction on ice.

According to Hagerty, only about cars were optioned with the liquid tire chain for 69, and most customers buying it were large car shoppers. The Liquid Tire Chain theory was sound. A control on the instrument panel activated a pair of aerosol canisters mounted above the rear tires that contained a chemical compound labeled Liquid Tire Chain Traction Improver.

Inside the canisters was a space-age polymer ready to coat the rear tires and turn slip into grip. Tyre Grip improved traction modestly during acceleration and braking, but any benefit waned after about one mile. With AutoSocks over the front tires, however, the car summitted many times. First, a thin film of liquid snow chain works better when it is as thin as possible, while evenly covering the whole surface of tire tred rubber.

Tire rotation is undertaken to ensure that the tires wear evenly. This can extend tire life and save you money. For example, failure to rotate tires on a front-wheel-drive vehicle will eventually result in the front tires having significantly less tread than the rear tires.

It is sharp and jagged and does more damage to standard tires than almost any other driving surface does. If a vehicle is equipped with off-road tires, gravel-covered dirt roads are not a major concern, but tires designed for highway travel do not typically fare well on gravel roads. Yes, tires do wear out faster on gravel and you get less mpg.

If the road is gravel that is dusty or the road is dirt the car will wear out much faster even though you change the oil 2x as often. High-end more expensive tires should last at least 2, miles. Racing bicycle tires, which are designed for speed and high-performance, may need replacing after 1, miles, but tough bicycle touring tires can last as long as 4, miles.

Also, front tires tend to wear more on the edges, and rear tires more in the middle. Since these things are true, not only would wear be distibuted more evenly on all four tires, but all four tires would wear more evenly across the tread face, and therefore wear longer.

Primarily, you should avoid mixing different tire brands and different tread patterns. There are rare exceptions for approved mixed-tire fittings, but in general, manufacturers do not recommend tire mixing at all. Mixing tire brands or even different models may cause handling instability. And when replacing only two, we recommend installing the new tires in the rear and placing the older but still decent rear tires in the front.

When the tires rotate, they catch the chains, greatly improving traction on icy or slick roads. You can see how they deploy and work in the video above. The automatic chain devices are typically seen on vehicles that need to be able to confront and cope with varying road conditions in a split second.

And while these types of vehicles are often heavy and more easily driven in snow, the chains can assist when they need to drive uphill. Now that you know, you can get back to taunting the kids staring at you from the back of the bus.