A process of rigorous evaluation over many years has gone into developing the new API CK-4 Diesel Engine oil range. Using new innovations like those provided by System Pro Technology, Castrol has been able to arrive at an extra performance reserve in which VECTON Long Drain 15W-40 CK-4/E9 exceeds minimum CK-4 specifications by up to 45 per cent in some instances.
The Australian market poses a unique set of driving conditions for road transport fleets whose operations must endure the daily challenges of inhospitable terrain and extreme, often sweltering weather.
As road train combinations locally are approved for loads that dwarf those in North America and Europe, the average fuel burn across Australian fleets is, according to Castrol field trials, 50 per cent higher than the US market and as high as 90 per cent more than in Europe.
As testing is often standardised for repeatability and consistency by the American Petroleum Institute and original equipment manufacturers (OEMs) across global markets, Castrol has fostered extensive further evaluations to ensure the extreme conditions of Australia have been factored into the performance of its CK-4 products.
If you can make it there, to borrow a line from a popular song, you can make it anywhere.
Claudia Sclosa, Castrol Lubricants ANZ Expert Technologist says data for the OEM service intervals has often originated overseas.
“OEMs that play a big part in our Australian Market will have their service intervals set by the global business after the required testing has been completed. Their local business will then take these recommended intervals and assess them for Australian conditions where they may be altered to allow for our road and weather conditions and our loads.”
For Castrol the process behind Castrol Vecton Long Drain 15W-40 CK-4, a part synthetic heavy duty diesel engine oil, which began when the company started testing additives to meet the new CK-4 requirements, was about delivering a long drain product endorsed and accepted by local transport fleets.
Castrol worked with some of its fleet partners including AHG Refrigerated Logistics to trial the CK-4 products to cover all seasonal temperatures and environmental conditions.
Covering over 2.5 million kilometres with 16 prime movers, the testing involved the latest engine technology offered by Cummins ISXe5, Detroit Diesel DD15, Mack MP8 and Volvo D13 and D16 G600 engines on a range of roadtrain configurations with mass limits upwards of 110 tonnes in some instances.
In a bid to confirm its oils would continue to perform beyond OEM recommended oil drain intervals, the oil drain intervals for VECTON Long Drain 15W-40 CK-4/E9 were extended out to 80,000kms.
As fuel burn is determined by several elements including environmental factors, driver input and the actual age of the truck itself, it was crucial for Castrol to not only exceed the original recommendation but go well beyond the approval rating in its evaluation process.
By analysing oil samples at regular intervals through an independent laboratory Castrol monitored levels of oxidation, viscosity, aeration and wear by looking at determining factors like Total Base Number, Total Acid Number, Kinematic Viscosity, soot and the metal quantities detected.
“When we actually ran the trials we tested and monitored about 18 different elements but wear elements were of major concern and these include iron, lead and copper,” Claudia says. “Acid build up in the engine oil can lead to corrosive wear. Acids are introduced into the oil via the combustion process of a diesel engine. We have formulated our latest CK-4 oil to maximise total base number and be able to neutralise acids for longer drain periods. Total Base Number and Total Acid Number monitoring during the trials proved acids are neutralised so that corrosion wear doesn’t become a problem.”
Measurements from the testing show that Castrol kept total acid number under control even when pushing past 50,000km, the recommended oil drain interval for severe duty application.
Extending the drain interval to 80,000km from which the ‘extra performance reserve’ is derived, the total base number averaged three times that of the total acid number, a generous reserve.
For fleet managers there is greater confidence knowing the risk of engine corrosion has been reduced especially when drivers might be prevented from making a scheduled stop on a long haul assignment.
Soot, a by-product of diesel engine emissions, was also monitored as part of the used oil analysis. As it can cause deposits of larger particles that are abrasive to engine surfaces, soot is best suspended in the oil so as not to affect the quality of oil film according to Claudia.
“Soot particles tend to act like magnets. Smaller particles attract each other to form larger ones that can be quite abrasive. This causes wear deposits that may collect on your ring liners increasing the chance of gas blow by leading to more acid formation resulting in corrosion and corrosive wear. It’s an endless cycle of related engine damage. We minimise this risk through the detergent dispersant chemistry that’s in the oil,” Claudia says. “Our results show that the chemistry is able to keep soot under control throughout the 80,000km drain.”
In that sense detergent cleans soot deposits on the metal parts of an engine while the dispersant keeps it suspended in a fine form preventing potentially harmful clusters. According to Castrol’s results, soot in the trial remained well below OEM limits – another advancement for longer lasting heavy duty engine oils.
Being a premium brand, Castrol, according to Claudia wanted a CK-4 product that delivered additional benefits for Australian operators, whose freight task, often with older equipment, is immense.
“The results of our trials are aligned with our Vecton brand and the System Pro Technology that provides that extra performance,” she says. “We don’t formulate with off the shelf add packs. We are actually involved in the development of the technology so that it clearly differentiates us in the market. Less frequent maintenance is a win for fleets and transport companies.”