The Globe and Mail

Something’s gone
wrong

We are experiencing an internal server error. Our engineers
are working to resolve the problem as we speak.

In the meantime, please visit us on Twitter to stay informed.

Go to the Globe and Mail homepage

Jump to main navigationJump to main content

(Getty Images/iStockphoto)
(Getty Images/iStockphoto)

You & Your Car

Does my car really need an oil change every 5000 km? Add to ...

I enjoyed your article on synthetic versus regular oil (tgam.ca/DszY). How about a column on oil change intervals? Old school was 5,000 kilometres. New school is much higher with the monitoring systems. – Egan

As engines and lubricants have evolved, this issue has become a popular topic with about as many opinions as leaves on a tree.

More Related to this Story

The factors that have remained constant are the three roles of engine oil: 1) to provide lubrication, 2) to carry harmful particles to the filter and 3) to act as a coolant.

Oil has always and still has to provide those vital services. But, over the years, engines, fuels and oils have improved dramatically. Modern oils are the result of extensive engineering, testing and scientific input. They are not only made from a much higher-quality base stock, whether petroleum or synthetic, they contain a number of additives to address specific roles within the three primary ones mentioned above.

Modern oils last longer and do a much better job during their useful life. Gasoline (and diesel) is much cleaner these days. Regulations around the world have forced refiners to clean up their act, so to speak. In the push for cleaner exhaust emissions, fuels are now much higher quality. This not only means cleaner exhaust, it means less contamination of the oil within the engine. And lastly, engines are built to much higher specs these days. Tolerances are tighter, variances from one engine to another far less and the casting, boring, drilling and assembly processes more precise. There are fewer nasty little metal pieces for the oil to carry to the filter.

Finally, your answer. Oil change intervals are much longer than they have ever been for the reasons stated above and because manufacturers have learned a great deal about what driving habits and scenarios place the most strain on engines and oils. By monitoring engine activity with sensors, the modern engine control computer can calculate oil change intervals.

The short answer? Follow the manufacturer’s recommendation and, if in doubt, change more frequently. If you have low-mileage vehicles, i.e., they accumulate very low mileage over a year, change the oil once a year. There is no scientific reason to do so, but it is cheap insurance.

Transmission

I just had the transmission replaced in my 2003 Honda Pilot, then I noticed something else right after the transmission change while accelerating. Once you step on the gas, it bogs down and you can hear the intake sucking. If you hold your foot down, it will backfire (pop) a few times through the intake and then it revs normally. If you touch the pedal lightly, it will rev normally. When coming to a hard stop, the motor will stall. I got my mechanic to increase the rpm and, at 3000 rpm, the car drives fine. I took it back to the mechanic and he replaced the fuel pump and filter, and yet it still reoccurs. I also have my VTM and check engine lights on. Any suggestions as to what I can do? How do I resolve this? – Ashinze

Take the vehicle to a Honda store and have them hook it up to their diagnostic system.

Engines and transmissions are much more closely integrated than in the past. The amount of information passed back and forth between the two every second would boggle your mind.

I suspect that the transmission swap was done without taking this into account. This has resulted in false or no information going to the engine from the transmission. In this age of tightly controlled emissions, any application of throttle, or request for more fuel, is accompanied by a raft of information about engine speed, throttle position, ambient conditions and the proper gear. Your engine and transmission are not communicating effectively.

Please send your automotive maintenance and repair questions to globedrive@globeandmail.com

Follow us on Twitter: @Globe_Drive

In the know

Most popular video »

Highlights

More from The Globe and Mail

Most Popular Stories