LIFT OFF: Lift axles continue to be phased out in Ontario, even in forestry where self-steer axles will replace them.
TIMMINS, Ont. – As Ontario continues overhauling its Vehicle Weights and Dimensions in an effort to phase out lift axles, many trailers used in the forestry sector are being targeted.
Phase 1 and 2 of the Ontario Vehicle Weights and Dimensions Legislation have already been reformed, including dump semi-trailers and one-, two-, three- and four-axle semi-trailers.
Phase 3, which is currently underway, targets all remaining semi-trailers and double trailers. Trailers manufactured in 2006 will have to be of a SPIF design or users of the equipment will face stiff penalties.
Existing equipment manufactured before 2006 will be grandfathered for 10 or 15 years.
Ron Madill of Ontario’s Ministry of Transportation was at the Forest Engineering Research Institute of Canada’s (FERIC) recent transportation conference to explain the reasoning behind the changes.
“The existing vehicle weights and dimensions are a highly productive regime,” he told delegates. “That’s not something we wish to disrupt.”
He said the province will continue allowing among the heaviest weights in North America. However, there are performance and safety-related issues concerning lift axles that need to be addressed, he said.
For one, they are simply bad for roads when misused.
“Lift axles are a particular problem. If they’re not taking their share of the weight, it has a dramatic impact on the dynamics of the vehicle,” Madill explained.
“Even when those axles are deployed we have studies showing that very seldom are those axles taking their proper weight.”
Changes to be phased in
In terms of safety, there have been cases where lift axles have been responsible for accidents as they tend to want to push the vehicle straight through a curve if not raised.
“It affects its stability and controllability (when you lift the axles),” said Madill.
“You’re taking eight tires off the ground. There’s also a risk of component failure.”
The province is looking at self-steering axles (Safe, Productive and Infrastructure Friendly or SPIF designs) as a viable alternative and Madill said SPIF trailers can manage similar gross weight capacities.
Studies have shown SPIF trailers cause about $7,000 per year less road damage compared to lift-axle equipped trailers. (In total, the province says lift axles cause nearly $300 million in damage per year.)
Madill emphasized the changes are being phased in over time.
“We’re not requiring that people change what’s on the road today,” he said.
“We don’t want to pull the rug out from under anybody. We are grandfathering (existing trailers) but putting a sunset on the grandfather so this will be a gradual migration to SPIF vehicles.”
Because trailers can be re-built to last many decades, the sunset is expected to be between 10 and 20 years.
Madill said developing SPIF alternatives is “one of the most challenging aspects of Phase 3.”
The province is already exploring alternatives involving self-steer axles, and Madill admitted there are some issues that have arisen.
“All of these issues are gradually being resolved as people are understanding how to spec’ and match these components,” he said. “Nothing has emerged that seems insurmountable with these axles.”
In mid-June, the province tested various configurations equipped with self-steer axles at testing grounds in Ohio.
Quebec is no stranger to self-steer axles, and Jan Michaelsen of FERIC spoke to delegates about that province’s experiences with the equipment. In Quebec, the lift mechanism must be entirely automatic or the control must be located on the trailer itself to avoid misuse.
Michaelsen likened the dynamics of a self-steer axle to the wheels on the bottom of an office computer chair – where the wheels simply respond to the movement of the vehicle and steer themselves.
FERIC has partnered with the Ministry of Transportation in Quebec to evaluate self-steer axles in severe service applications.
“We were really focusing on the operational (aspect) – can it perform as well and what are the maintenance issues?” explained Michaelsen.
A chip van and log trailer were both equipped with self-steer axles for the study. Immediately, the trailers were burdened with an additional 135-154 kgs of weight and the cost of the equipment was an additional $4,500.
It’s worth noting these trailers were equipped with wide-based single tires not yet permitted in Ontario.
“You’re going to have a weight penalty with these (self-steer axles),”acknowledged Michaelsen.
Some of the maintenance-related problems included: king pin wear and king pin housing wear; accelerated wear of the tires on the self-steer axle and the last tire of the tridem; and the self-steer axle geometry slipping out of calibration twice.
The project wasn’t helped when the logging trailer was involved in an accident that the driver blamed on the self-steer axle (an independent investigation indicated the self-steer axle wasn’t responsible for the rollover, however.)
“The driver’s still not convinced,” admitted Michaelsen.
One of the biggest concerns was tire wear.
On the chip van, the self-steer tire only lasted 100,000 kms and the third tridem tire lasted 185,000 km. On the log trailer, the self-steer axle tire lasted a measly 50,000 kms.
In the case of the chip van, there was a net annual gain of $2,800 because payload was increased marginally (that may not be the case in Ontario, pointed out Michaelsen.) The log trailer experienced a net annual loss of about $1,025.
“We think the axle is robust enough,” said Michaelsen. However, he did say there’s about a $5,500 purchase price increase, tire wear remains an issue and there will be a weight penalty as well.