Oil cold comfort for new cars

Press, 30 August 1989, Page 2

Oil cold comfort for new cars

MICHAEL RENTOUL

The use of a low-grade oil, 30/ 40, could damage late-model cars, particularly in Christchurch’s cold weather, says the Consumers’ Institute director, Mr David Russell.

He was responding to a warning yesterday by Castrol New Zealand, Ltd, that 30/40 oil, typically marketed in four-litre take-home packs, was of a standard not suitable for modern engines and could result in warranty claims being ruled invalid. The Consumers’ Institute had shown the oil companies a copy of an article on 30/40 planned for its September edition of “Consumer.” Mr Russell said the oil companies were heavily promoting 30/40, some without telling the motorist which cars it suited.

Sophisticated modern engines required oil of greater viscosity and consistency than 30/40, es-

pecially in colder temperatures. A modern car which made a lot of short runs on cold starts using 30/ 40 would be particularly at risk of engine damage. Not only could 30/40 starve some engines of oil, some brands did not have cleansing abilities.

Mr Russell knew of no cases where a car manufacturer had refused a warranty claim because 30/40 had been used instead of the recommended grade of oil, but said it was possible. Castrol’s technical director, Mr Stewart McDonald, said a loophole in the oil standards classification was resulting in oil being sold which was of lower quality than the standard quoted. An oil manufacturer could put an out-of-date standard on a pack to avoid having the oil tested, he said.

SAE 30/40 and SAE 25W grades

were considered invalid and no longer tested. Another oil measure, API, had obsolete grades. Only API SF and API SG were still measured, he said. Car manufacturers specified either API SF or API SG rated oils in most cars made after 1980.

“Warranty claims... may be affected if an incorrect grade is used," Mr McDonald said. “As long as motorists believe that all oils are much the same and buy on price, oil manufacturers will compete on price. “It is easy in the uncontrolled 30/40 market for unscrupulous manufacturers to achieve a low price by leaving out the expensive additives which give oil a longer life and better wear protection. “There is a market for 30/40 oil for old cars. However, that market should be declining, not expanding.”