Truck News

Feature

Research group says tridem drives the way to go

EDMONTON, Alta. - Tridem drive trucks are becoming an increasingly familiar sight on western Canadian highways, and those who use them have a little-known forestry research group to thank.B.C.-based F...


TAKE A LOAD OFF: Amlin says tridem drives offer a safer ride through stability.
TAKE A LOAD OFF: Amlin says tridem drives offer a safer ride through stability.

EDMONTON, Alta. – Tridem drive trucks are becoming an increasingly familiar sight on western Canadian highways, and those who use them have a little-known forestry research group to thank.

B.C.-based Forest Engineering Research Institute of Canada (FERIC) has been testing the 8×6 tridem drives for 10 years, and their research has been instrumental in getting the drives approved for highway use.

Although FERIC works almost exclusively with logging companies while conducting research, the results are now being enjoyed by heavy haulers in other industries as well.

Eric Amlin, group supervisor of transportation and maintenance, says “The forest industry really pioneered it and now there are other sectors where tridem drives are starting to appear.”

He notes that the Ready-Mix industry in B.C. is the latest to file applications for the use of tridems.

The logging industry is unique in that it can call upon a research group such as FERIC to evaluate the effectiveness of new ideas.

Big players in the industry are constantly looking for better ways to carry out their business, and FERIC is a major help in determining the value of new techniques.

Their work with tridem drives has seen almost every configuration approved in western Canada over the past 10 years. But it didn’t happen overnight. Amlin says that it takes between one and two years to adequately test each configuration.

“Every time you couple the tridem drive truck with another kind of trailer type the government requires another study because the trailer is influenced by what the tractor does,” explains Amlin. “It’s prudent to do evaluations with each new trailer.”

The first trailer type that was paired with a tridem drive under FERIC’s microscope was a pole trailer. FERIC studied the results in the field and through computer simulations and found that there were some major benefits to operating tridem drive tractors.

“Our initial test was to verify that they did offer improved mobility over tandems and to measure how much that was,” says Amlin. FERIC found that traction improved by 50 per cent over the traditional tandem drive trucks.

“What that means is that industry doesn’t necessarily need machinery on-site to tow trucks anymore and that saves substantially on their wood costs,” says Amlin.

But proving that tridem drives provided better traction wasn’t enough to convince the government that they should get the green light to run the province’s highways. There were a series of other concerns raised by government.

“We set about to address those concerns which were mostly safety and steering performance related,” says Amlin.

The wheelbase, the load on the steering axle, the load on the drive axle and the spacing of the drive axles were scrutinized. But in the end, FERIC was able to convince the province of Alberta that tridem drive trucks provided not only better traction, but also more stability.

Alberta was the first to approve widespread use of the trucks, and then FERIC started the process over in B.C. where different weights and dimension restrictions meant a whole new set of regulations had to be met.

Although it was a long time coming, FERIC’s research eventually led to the approval of tridem drive trucks for all typical log-hauling configurations in B.C. and Alberta.

But there are some drawbacks to the new fad. Amlin admits they do use more fuel, but insists the benefits outweigh any additional fuel costs.

“Of any of the trucks we monitored the increase in maintenance costs has been minimal,” says Amlin.

And while there are naturally more tires to replace on a tridem drive than that of a tandem drive tractor, it all balances out because there would typically be fewer tires to replace on the trailer.

All things considered, FERIC is quick to support the use of tridem drives in the logging industry.

“Industry is getting a vehicle that is more productive,” says Amlin. “Our findings continue to reinforce that a tridem drive is a more stable truck than the typical tandem drive and that’s really a big motivator for us in encouraging the use of it.” n


Print this page


Have your say:

Your email address will not be published. Required fields are marked *

*