Date: Fri Jun 20 01:48:17 2008 Back to Contents

Author: Machele Kindle

Subject: Re: myth of oil change every 3,000 miles


My first husband and, sometimes me, commuted a LONG WAY to work (when I
worked between semesters). It was 180 miles each day for us and we
couldn't car pool often. So, needs to say, we did the 3 month limit of
the 3 months/3000 miles rule. That means we were changing every 11k
miles. We never had a problem.


Jerry DiMarco wrote:
> Sounds like a potential science fair project. I started changing
> oil every 3000 miles when I read a Consumer Reports survey about
> habits of car owners whose cars lasted the longest or something like
> that. Guess it's time to reconsider, and just in time since I'm
> getting tired of doing it twice a year...
> Jerry
> At 6/17/2008 09:29 AM, you wrote:
>> Read this in the yahoo news, concerning the myth of changing the oil
>> in a vehicle every 3,000 miles.
>> Idea for new experiment in the physics labs or something already
>> being done?
>> SR
>> *******************************************
>> 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.

For in the end, we will conserve only what we love.
We will love only what we understand.
We will understand only what we are taught. - Baba Dioum

From Fri Jun 20 01:48:17 2008