Posted on 06/17/2008 7:19:00 AM PDT by Disturbin
According to a recent study by the California Integrated Waste Management Board, 73 percent of California drivers change their oil more frequently than required. This same scenario no doubt repeats itself across the country. Besides wasting money, this translates into unnecessary consumption of $100-a-barrel oil, much of it imported.
Using 2005 data, the Board estimates that Californians alone generate about 153.5 million gallons of waste oil annually, of which only about 60 percent is recycled. Used motor oil poses the greatest environmental risk of all automotive fluids because it is insoluble, persistent, and contains heavy metal and toxic chemicals. One gallon of used oil can foul the taste of one million gallons of water.
It’s been a misconception for years that engine oil should be changed every 3000 miles, even though most auto manufacturers now recommend oil changes at 5,000, 7,000, or even 10,000 mile intervals under normal driving conditions.
Greatly improved oils, including synthetic oils, coupled with better engines mean longer spans between oil changes without harming an engine. The 3000 mile interval is a carryover from days when engines used single-grade, non-detergent oils.
For several years, automakers like General Motors, BMW, and Mercedes-Benz have installed computerized systems that alert drivers via an instrument panel light when it’s time to change oil. As an example, the General Motor Oil Life System (GMOLS) analyzes the engine temperature, rpms, vehicle speeds, and other driving conditions to calculate the rate of engine oil degradation. Then, software calculates when the oil needs to be changed. Other systems work similarly.
Because of the many external conditions and parameters that have to be taken into account, calculating the precise maximum service interval using mathematical models alone is difficult. Now, Daimler AG has developed a more direct and precise way to monitor oil quality directly on board a vehicle.
Daimler uses a special sensor integrated into the oil circuit to monitor engine oil directly. Oil doesn’t wear out, but rather dirt and impurities cause oil to lose its ability to lubricate properly, dictating the need for a change. Daimler uses the oil’s “permittivity,” that is, the ability to polarize in response to the electric field. If the engine oil is contaminated by water or soot particles, it polarizes to a greater extent and its permittivity increases.
To evaluate the quality of the oil, permittivity is measured by applying an AC potential between the interior and exterior pipes of an oil-filled sensor to determine how well the oil transmits the applied electric field.
Because not all impurities can be measured with sufficient precision via the electric field method, Daimler also measures the oil’s viscosity to detect any fuel that may have seeped into the oil. Daimler researchers measure viscosity while the vehicle is in motion by observing the oil's side-to-side motion in the oil sump. The slower the oil moves, the higher its viscosity. This movement is registered by a sensor and the viscosity is calculated on this basis.
A single sensor, along with the information already monitored by on-board computers, is sufficient to determine the various parameters of the engine oil. Daimler will likely use the technology first on its commercial vehicles. Here, large oil reservoirs mean larger quantities of oil can be saved. Plus, a predicted 25 percent increase between service intervals and reduced downtime will be of interest to fleets, and thus justify the added cost of installation.
After your knee jerks have finished, maybe we can address opinions about this:
" ... most auto manufacturers now recommend oil changes at 5,000, 7,000, or even 10,000 mile intervals under normal driving conditions."
Roger that. This "story" reads like a press release from Daimler.
Now that oil changes are covered by factory warranty, my BMW only requires it ONCE A YEAR (14,000 miles).
I still think I’ll pay for one at 5-6,000! LOL.
Remembers back in the 60’s a fella that drove a chevy corvair with over 100K miles on it.
Claims he NEVER changed the oil one time. We’d always joke about it and he’d just smile and head on down the road..
His name was Ralph..Ralph Nader, yea, that’s the ticket. jk
Yep. And it gets all burnt up and stuff. Not fun.
You never owned a '75 Plymouth Valiant, apparently. (or a 1985 Renault Alliance, or a 1973 Ford Pinto, or a 1976 Chevy Vega)
I had a blazer (’93, V6 Vortec, all original) that was the same way. Ultra-reliable until it hit 296k and cracked a seal. My cousin’s rebuilding the engine to give the thing to his son.
I use Amsoil oil and filter, and change every 25k miles. But, if switching from Dino-oil to synthetic, you should flush the engine first.
Why do you say that...?
What they mean is that the oil molecule itself doesn't wear out. If there is no contamination, you wouldn't have to change it. See manual transmissions, differentials, and other sealed systems.
Yea, I’m lining up to buy a used car from you . . .
What you say is correct except unless the oil was overheated such as blowing a radiator hose or such. Getting oil hot will crack down the molecules and change it’s properties.
When I was 16 back in the mid to late 70’s (ahem!), I drove a Gremlin. I drove that baby for 8 years and never once changed the oil. What did I know? Was still running fine when I sold it.
according to wikipedia (yeah, i know):
One form of synthetic oil is that manufactured using the Fischer-Tropsch process which converts carbon dioxide, carbon monoxide, and methane into liquid hydrocarbons of various forms.
Another form of synthetic oil is that produced at Syncrude sands plant in Alberta, Canada. This huge facility removes highly viscous bitumen from oil sands mined nearby, and uses a variety of processes of hydrogenation to turn it into high-quality synthetic crude oil.
The old piston engined airliners with large radial engines did not ever change the oil. The entire maintenance procedure was to drain the oil sump and clean the oil screen, then top off the oil tank.
That explanation makes sense. Thanks.
Just adding new if it is low is all you need, I would guess.
I have a Plymouth Voyager, nine years old, with 126,000 miles. Tranny fluid and filter was last changed at 90,000 miles.
Any suggestions about changing the trans filter? I’m thinking that a new filter will be needed one of these days. Just change the filter and reuse the old fluid to avoid the new stuff?
My Dad use to sometimes pour the used oil onto our dusty driveway to keep the dust down. It worked, but can you imagine doing that today?
You’re right. Too much heat puts a fork in it.
Which was more because of body and chassis corrosion and cooling system failure (again due to corrosion) than due to engine mechanical problems.
I've seen many a Dodge Dart corroded to junk with a perfectly serviceable slant six under what was left of the hood.
Also take note that most European cars have oil change requirements much less strict than US cars. 6K to 10K oil change requirements for Mercedes and BMWs are not uncommon, yet there are a lot of Mercedes cars in the million mile club.
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.