I t’s been a busy four years for
the makers of heavy-duty onroad diesel engines and no less so for the
producers of lube oils for these engines. Both groups have been scrambling
to meet the latest round of deadlines imposed by the Environmental Protection
Agency. All on-highway diesel truck engines manufactured from that day
forward will have to emit fewer emissions and these new engines will
require new lube oil. The good news is that the operational impact of
these regulations on contractors has been minimal for the most part.
The new engines are more expensive, but they’ve also become better
and more efficient. The only change contractors and fleet managers have
to make is in their preventive maintenance and the type of lube oil
they use.
CJ-4 is not a jeep
The official spec for this new oil is the American Petroleum Institute
CJ-4 category. (The CJ-4 name has nothing to do with Chrysler’s
everpopular Jeep. It’s just the next extension of a series of API
specs - from CH-4 to CI-4, then CI-4+ and now CJ-4.)
The new oils have lower levels of phosphorous,
ash and sulphur - additives that, if used in the 2007 engines, would
increase maintenance and lower the performance of the exhaust aftertreament
devices (diesel particulate filters and diesel oxidation catalysts)
these engines need to produce cleaner exhaust. The new oils also have
higher oxidation stability (resistance to breakdown in high heat situations)
and soot dispersant capabilities - two conditions that get more severe
in the new engines.
“Ash can plug up the diesel particulate
filter and when it is plugged up for a period of time it can cause back
pressure, which has a detrimental effect on the whole engine,”
says Reginald Dias, Director, Commercial Products, ConocoPhillips Lubricants,
Conoco brand.
“The high levels of phosphorous
and sulphur could have a negative effect or deactivate the catalyst
in an oxidation catalyst. These aftertreatment devices are supposed
to be warranted for 150,000 miles, but when you have higher ash, phosphorous
or sulphur levels, that warranty could be voided,” he says.
How much it will cost to clean a DPF
or oxidation catalyst has not been clearly established yet. Dan Arcy,
technical manager for Shell Lubricants, estimates it may run from $300
to $500, not including a half day or so of downtime. It is likewise
uncertain to how much more frequently you would have to clean the aftertreatment.
A likely scenario is that if you were getting 150,000 miles between
cleanups with the CJ-4 oil at 1-per cent ash and you put a 1.5-per cent
ash product like CI-4+ into your engine, you may only get
....CONTD
