NATM convention coverage: SAE's formation of Trailer Brake Task Force to lead to Information Report or Recommended Practice
THE National Association of Trailer Manufacturers (NATM) was a key player in jump-starting work toward a brake standard for light- and medium-duty trailers that led to the Society of Automotive Engineers' (SAE) formation of the Trailer Brake Task Force and will ultimately lead to an Information Report or Recommended Practice (RP) that will be published first as an SAE J Doc.
State laws vary dramatically: As of 2009, six states had no statute on a minimum GVWR for brakes. Twenty-one states required brakes for a GVWR over 3000 pounds. Two states required them for over 10,000.
“We wanted to act accountably to contribute toward a safer US towing environment. There isn't a test procedure for brakes — not even a performance criteria for brakes — so before you can say something needs brakes, don't you need to be able to test to see what it does need for brakes?” said Clint Lancaster, NATM's director of engineering and technical services, who moderated a panel including Titan's Randy McMann, UFP's Bernie Goettker, Dexter's Tim Meckstroth, and Al-Ko Kober's Larry Revelino.
So NATM coordinated an effort involving RVIA and BTMA to develop an industry work group that was initially five members from each organization, including a mix of trailer manufacturers and component manufacturers. Last year, they added all of the brake system component manufacturers for industry consensus and buy-in.
“We reached out to all the component manufacturers. We got the whole universe of brake manufacturers and systems. We've been working on it two years.”
Lancaster said the group researched everything it could find, including standards for ISO, Europe, Australia, and Canada, along with past National Highway Traffic Safety Administration (NHTSA) studies, and came up with almost 30 documents.
It developed a draft standard document with references, test conditions, road-test procedure and performance criteria, dynamometer-test procedure and performance criteria, and component compatibility for hydraulic systems.
Testing procedure
The brake standard includes both electric and hydraulic brake systems and will be a testing procedure to meet performance criteria.
“It's both a laboratory and trailer test,” Lancaster said, “so these guys will be able to use test procedures in dynamometers and labs to test to the standard. It will allow trailer manufacturers to design braking systems for their particular units, especially units that have different dynamics or centers of gravity.”
The stated goal: “Improve the overall safety of small to medium sized trailers manufactured for use in the US by creating a standards document that details general US requirements and performance tests for light- and medium- duty trailer brake systems. It should be constructed in such a way as to provide for simple, yet effective testing that can be performed either in a laboratory setting for more sophisticated organizations or as a simple road test in order to accommodate smaller organizations. The test procedure would accommodate both electric and hydraulic braking systems.”
It has been passed on to SAE for a standard process that he says will “bring together knowledgeable, interested individuals that can efficiently enable”:
- A clearly documented, reasonable braking standard that makes sense to all stakeholders.
- An easily interpreted set of testing procedures that are reasonable to execute repeatedly.
- Resources to validate the standard and the procedures.
- Distribution and acceptance of the standard by the stakeholder population.
SAE has formed the Trailer Brake Task Force. An Information Report or Recommended Practice will be published first in an SAE J Doc. NATM will add to the Compliance Verification Program Checklist as a recommendation.
Once brake manufacturers have adopted and implemented the J Doc, NATM will move to the compliance portion of the checklist.
“There are SAE standards out for testing combination vehicles — the vehicle and trailer together, J134 and J135,” Lancaster said. “This is to test the trailer brake only. The concept behind it is, we have calculated formulas that you'll use when you do your braking to basically pull the vehicle out of the equation.”
Talking about the brake dynamometer, Dexter's Meckstroth said: “It has programmable sequences. One of the advantages is you can put it on, program it, walk away, and come back. It doesn't show the whole braking system, but isolates the brake performance outside conditions and the tow vehicle. It's convenient and isolates the brakes. We run this thing a lot.
“You can run that trailer test with different lines if you want to see the impact of what flexible line, an extra 20 feet, is doing — not just to the brake pressure but the response time. You're slowing down your response time. People are taking a look at both sides of the equation: brakes only and system performance. You can do it for both hydraulic and electric brakes up to 10,000 pounds.”
Lancaster said it will still take a “long time” to finalize the standard.
“Once your brake engineers put in a brake standard, we need some people in the industry to put some checks and balances in the system for us,” he said. “I don't think you want just component people doing this because this impacts the end user a lot. So we have a plea for trailer manufacturers who have any interest in hanging out with bunch of brake engineers. A few would be very useful. We need them. We don't want to make a standard that's good for four brake engineers.
“We don't want to be testing a 10-inch brake with a 20,000-pound brake actuator. So there is a little bit of math coming into this thing. We have it for the hydraulic side. Now we need it for the electric controller side. That's where we're kind of hung up at. So we're going to get with the controller manufacturers and see if they can help us put together something that would be a control factor for the size of brakes and size of the input.”
Lancaster, addressing the importance of being proactive, referenced the comments of NHTSA administrator David Strickland.
“One of things he said is that you don't want somebody coming in and cleaning your house,” Lancaster said. “It's better if you clean it yourself.
“I think if we don't start this and establish it for ourselves, it would be real easy for them to take commercial regulations from FMCSA, which is brakes on all axles over 3000-pound GVWR vehicles, and put it right into the NHTSA standard, which would affect us as manufacturers. They have done a lot of work on brakes for vehicles. They had FMVSS 105, and they just did a new one called FMVSS 135. We want to make sure we're ahead of the game and taking care of what we need to take care of and also help manufacturers out there try to get their hands around something to help them with trailers. That's the long-term goal.”