Oil Changes?: Grassroots Motorsports forum: Grassroots Motorsports Magazine

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Feb. 19, 2011 11:36 a.m. HappyJack Reader

I've always been taught to change my oil regularly. Every 5000 kms (3000 miles) without fail. If not, sooner if there have been some hard miles.

I recently purchased a fully loaded 2002 Ford Explorer, Eddie Bauer edition. It has more options, bells and whistles than I've ever had, or know what to do with.

One of the options this truck has is a monitor telling you the "life of the oil". I'm almost due for an oil change according to the odometer, but according to the gauge, I still have 58% life left.

How accurate are these? Or are they just a gimmick? I'm probably gonna change the oil anyway, but should I put any stock in what this gauge says?
Feb. 19, 2011 12:15 p.m. 93gsxturbo HalfDork

Modern vehicles with modern oil, running modern high quality gasoline do not require oil changes as frequently.
Feb. 19, 2011 12:39 p.m. paul Reader

Go to Go to http://www.bobistheoilguy.com/forums/ubbthreads.php , lots of great info & results of oil analysis.

If oil life monitors were not to be trusted, manufactures wouldn't of spent the time to properly engineer the technology.

Unless you're towing heavy loads or in extreme temps etc, I'd either go by the oil life monitor, or stick to the non-severe oil change interval. , lots of great info & results of oil analysis.

If oil life monitors were not to be trusted, manufactures wouldn't of spent the time to properly engineer the technology.

Unless you're towing heavy loads or in extreme temps etc, I'd either go by the oil life monitor, or stick to the non-severe oil change interval.
Feb. 19, 2011 12:41 p.m. Hasbro HalfDork

In reply to paul:

http://www.bobistheoilguy.com/cms/
Feb. 19, 2011 12:51 p.m. fasted58 New Reader

I like Blackstone Labs for oil analysis, at minimum once per year per vehicle, it's cheap insurance.
Feb. 19, 2011 12:54 p.m. Flogger00 New Reader

They're accurate. They're usually based on algorithms which include things like ambient temps, rpms, how much highway use and the like. They don't actually test the oil, of course, but they tend to be good estimates. They don't, however, know about things like, say, you're running a good synthetic and the owner's manual specifies dino oil. Or you emptied a can of FI cleaner into a throttle body, filled a cylinder and it leaked down into the crankcase, or you have an injector that leaks after shutoff, further contaminating the oil. In other words, assuming the computer's assumptions are right, then they're pretty accurate.

One caveat - some of them tend to be biased towards reducing the cost of ownership during the warranty period for marketing purposes.

Also, even for older cars not designed to squeeze every cost effective drop of life out of their oil, 3000 miles is now considered very conservative. For the most part, oils have gotten better over the years.
Feb. 19, 2011 1:09 p.m. mad_machine SuperDork

even on my older cars.. I tend to do 4500 miles between changes
Feb. 19, 2011 1:34 p.m. EvanR Reader

Unless you are towing at max GCVW, uphill, through the dusty desert, virtually no one needs 3k oil changes.

5k on dino, 10k on good synth.
Feb. 19, 2011 1:47 p.m. ironhead New Reader

Lot of controversy here... Most manufacturers define Severe duty as any 2 of the following conditions. Towing Driving in dusty conditions or on dirt roads. Extended periods of idling. Extended periods of high speed driving. Stop and go driving. Driving in hilly or mountainous areas. Climates with large temperature changes. Extreme hot or cold climates.

The biggest problem with extended oil change intervals is not that the oil breaks down, but that it becomes contaminated with dirt, moisture and byproducts of combustion. Newer engines are better equipped to reduce byproducts of combustion and are a little better filtered to reduce dirt, but moisture is still a big problem. I dont care how much you spend on your oil or what pretty colors are on the bottle, if it is left in the engine long enough, especially in humid areas or places with large temperature changes, you will end up with a certain amount of moisture in the oil. Companies making synthetic oils that advertise 10k+ intervals all put in fine print that you are supposed to send an oil sample in for analysis at 5k and every 2k after that. If you do that and the analysis comes back good, leave it in there. but if you arent going to have the oil checked for contaminates, you should be changing it at 3-5k depending on your driving habits and climate. Guy
Feb. 19, 2011 2:51 p.m. Nitroracer SuperDork

EvanR wrote:

Unless you are towing at max GCVW, uphill, through the dusty desert, virtually no one needs 3k oil changes.

5k on dino, 10k on good synth.

I go by this as well. Change every 5000 miles and its easy to track on the odometer. No super special oils just stay on top of basic maintenance. ( I run 6qts of ford oil @ $2.75ea and a delco oil filter)
Feb. 19, 2011 3:27 p.m. Streetwiseguy Dork

As long as you are using an oil that is approved for the vehicle, the oil life monitor will take into account the style of driving you do, the temperature extremes, etc and will be accurate. My Chev pickup surprised me by kicking the light on at just under 5,000 km, but I had towed my race car 1,200 km twice in the heat of the summer on that change.

Remember that first sentence I wrote. The engine doesn't care that your Grandfather always used Oileyoil refined from the carcasses of blue throated hummingbirds. If it doesn't say on the bottle that its approved for your engine, DON'T USE IT!
Feb. 19, 2011 3:44 p.m. Zomby woof Dork

I can get 20,000 km on my Canyon between oil changes. Since I use good oil, it doesn't bother me. The dealer says it's not out of the ordinary for light highway use.
Feb. 19, 2011 4:34 p.m. 93EXCivic SuperDork

Slightly on topic. If a car says to use full synthetic do you really have to?
Feb. 19, 2011 5:53 p.m. bruceman Reader

93EXCivic wrote:

Slightly on topic. If a car says to use full synthetic do you really have to?

I assume you don't have a talking car. Generally an owners manual recommends to use an oil that meets a specification such as GM4718M, GF-5 or dexos1. I like to do what the owners manual sayes.
Feb. 19, 2011 6:36 p.m. 93EXCivic SuperDork

That E36 M3s expensive. And it seems hardly worth in a car which is falling apart (this isn't my car).