Change Oil Light

[magic1872]

How does that work. I've noticed that is does not come on after 3,000 miles. My dad has a Cady STS and what his car does is test the oil and tell him how much life is left. When it gets time to change it, the oil light comes on. Just wondering if our cars do the same.

[sac2165]

I don't think it comes on exactly at 3000, but I think it comes on at regular intervals...

[Red2K1]

As I understand it, the oil is not tested as some think. What the monitor keeps tract of is miles and speed. In other words, a car that is driven in city stop and go traffic will need to have the oil changed more frequently than a car driven at normal highway speeds and under light load. What the monitor tries to balance is miles and engine load.

In any case, under "normal" driving circumstance the oil and filter should be changed somewhere between 3,000 and 3,500 miles unless the engine is operated under heavy load and then the oil and filter should be changed before 3,000 miles.

Some will argue that synthetics hold up for a much longer interval, even under heavy engine loads, than regular oils, but no one can seem to put a number on the difference between the two types of oil and prove it. The proof may be there, but I have not been able to find it.

That is the way it was explained to me by a GM tech.

[V6Bob]

"What the monitor keeps tract of is miles and speed."

I think it also counts engine starts or maybe just cold starts. It would be interesting to know the exact equation it uses. In any event, mine seems to come on between 5-7K miles.

[9t9fb]

<blockquote>quote:</font><hr>Originally posted by V6Bob:
"What the monitor keeps tract of is miles and speed."

I think it also counts engine starts or maybe just cold starts. It would be interesting to know the exact equation it uses. In any event, mine seems to come on between 5-7K miles.<hr></blockquote>

Do you have the oversiezed oil filter?
Because since i got the biger filter my light doesen't come on until around 5500-6500 miles.