The reasons behind fleets’ reluctance to shift to the new CJ-4 oils, concerns about replacing DPFs and the debate over the benefits of nitrogen inflation were some of the thorny subjects raised during the “Shop Talk with the TMC” session at this year’s CFMS.

TMC’s John Sullivan and Darry Stuart fielded questions and comments from maintenance managers and industry suppliers alike during the informative discussion, but nothing left both the moderators and those in attendance scratching their heads more than the problem of how to deal with moisture in differentials.

A manager from a Maritime fleet complained of finding a milky white watery substance in the differentials of trucks that have been on the road just nine months. The fleet was using a synthetic lubricant and the fleet manager was baffled as to what may have been the cause.

“How does the water get in? Nobody can tell me,” the exasperated fleet manager said. He added he was thinking of switching to a mineral-based oil to see if that would help re- solve the problem.

Stuart, however, warned against taking such action.

“I have seen this happen before and I don’t know what can be done to fix it,” he acknowledged. “But I do know that synthetic lubricants are like a sponge. They absorb moisture. I don’t know if I would go back to a mineral-based oil. You may be creating more problems.”

Stuart recommended sticking with the synthetic but switching to a different brand for a year to see if that would make a difference.

Others suggested checking the vents, although another TMC representative said that while “breathers” that allowed water to get into systems used to be an issue, it has not been one for many years. Another session participant suggested the vent in the differential may be too small and the differential manufacturer may have to rethink the size of the vents, adding that too was a problem in the past.

Yet another session participant suggested the water in the system may be condensation related to how the trucks were being used. If they were running hot over relatively short distances and then allowed to sit, they would not have the opportunity to burn up the moisture.

“I’ve been turning wrenches for a long time now and I’m seeing more water (in systems) than ever before,” he said.

Perhaps the wisest comment came from the industry supplier who suggested analyzing the makeup of the milky fluid found in the differential as the first logical step towards understanding what may be causing the problem.

Less controversial was the subject of industry adoption of the new CJ-4 oils. They were designed to run in the 2007 engines, but it appears many fleets are sticking to the older CI-4 oils.

“The majority of fleets (at a recent TMC meeting) told us they were not changing to CJ-4; they’re running still with CI-4. That kind of blew us away,” Stuart said, adding that while the pricing levels between the new oil and the old oil may have been the initial reason, the old oils seem to be holding up in the new engines.

An oil company representative, however, added fleets are missing out if they’re resisting the new motor oil formulation.

“It provides longer life and is a superior product. And CJ-4 is backward compatible. Our field trials indicate that oil drain intervals would remain the same (as long as ULSD is being used).”

Extending drain intervals is one way fleets are looking to deal with the impact of rising costs for oil products. The average over-theroad US fleet is employing a 45,000-km drain interval. A quick poll of the maintenance managers in attendance at the session found considerably more variability in Canada, with drain intervals ranging from 30,000 km up to 60,000 km.

“If we can save two oil changes a year, that’s money in our pocket. We should be going longer with the new (CJ-4) oil and Petro- Canada assures us that we can. Maybe we should be putting our heads together to see how long we can go,” one maintenance manager said.

Stuart added that some fleets in the US are even trying to push drain intervals to 100,000 km and selling the truck afterwards.

But one long-time fleet maintenance manager from a northern Ontario fleet questioned the wisdom of messing with drain intervals.

“There are two basic things that keep an engine running: fuel and lubrication. Why screw with that? I don’t play with my oil service intervals. As expensive as it may seem, when you take your lube cost and stretch it over the life of a truck -as a 10 to 15-year investment -it’s really not that much,” he said.

His fleet’s policy on service intervals has not changed with the new oils.

“I find the old way is still the best way,” he said. Stuart said the reason fleets are experimenting with new maintenance strategies may be “because we have no idea how to manage for the current cost of fuel,” but also because in the US, the “doctors of iron” -the traditional maintenance managers -are disappearing as US carriers go public.

“It’s not about hauling freight anymore, it’s about selling shares. The average shelf life of a maintenance manager in the US is three to five years. Maintenance is starting to be controlled more and more by bean counters than common sense maintenance strategies,” Stuart lamented.

One product that may have suffered particularly from this industry trend is the disc. Although disc brakes dominate the European market, this pricier but arguably more effective component has not made much headway in the North American market.

There is an issue, however, with the need to outfit not just the tractor but also the trailer with disc brakes in order to get proper braking performance.

“The problem a lot of the fleets have in the US with adopting disc brakes is the bean counters ask how much it’s going to cost. So the feds are going to do it through mandating stopping distance. The only way to comply will be by going to disc brakes,” said TMC’s Sullivan. “We are hearing a lot of noise about it. It’s going to happen.”

Stuart concurred, adding that the fleets that opt for an early adoption strategy will have a competitive advantage.

Nitrogen inflation was another issue that seemed to have no straight answers.

One fleet manager outlined how his fleet had installed a nitrogen inflation setup in one of its nine garages and was hoping to save about 1% on tire costs as a result because of the perceived benefits of tire inflation, namely cooler-running treads and no rust creation. Its current system was capable of filling less than 10 tires per hour and the fleet was looking to purchase a more robust system.

Stuart, however, was skeptical.

“If you are looking for a 1% savings, then you really need a system that can accurately track tire costs,” he advised, adding that in his experience with an Arizona-based fleet that experimented with nitrogen inflation, there was no advantage provided beyond what a well thought out tire maintenance program would provide.

“You really have to test it and check the numbers yourself. I see a lot of fleets that, surprisingly, don’t have a tire program that covers all the basic principles of tire maintenance that seem to want to cover their sins by going off on some tangent.”

Discussions about the ’07 engines have proved lively over the past year, but not this time around. Less than a handful of the maintenance managers at the CFMS session worked for fleets that had invested in the new engines (our own research shows that the pre-buy included up to 40% of Canada’s largest for-hire fleets) and the ones that did were having few problems. Initial issues with the wiring are being resolved, according to the experience of one fleet in attendance that was using the new engines, and fuel performance has improved over the previous engine models by up to 3%, while drivers are no longer complaining about insufficient power.

However, Sullivan cautioned that the availability of diesel particulate filters may prove to be an issue.

“It can be an issue if you wreck a new truck. Does the dealer really have a DPF in stock or will you have to wait three to four weeks for it? Just because you’re not supposed to have a maintenance issue with DPFs for 100,000 km doesn’t mean you won’t have an availability issue,” he said, adding:”It’s worth a phone call to your dealer.”

To which one fleet manager retorted: If the dealer didn’t have a DPF in stock, “If they have a new truck on the lot, the DPF is coming off if they want to support the business.”