As I'm sure is the case with many of you, money is for me tight right now. I live downtown in a city of about half a million people. I drive about 10,000 miles a years, rarely making trips longer than 10 miles(at most). I use Mobil 1, and have not changed my oil since September, as I've just reached the 3,000 mile mark on the oil. I normally change my oil at 3,000 miles on the oil to be on the safe side. My oil life monitoring system say I have 57% of my oil life remaining and since money is tight, I'm debating weather or not to delay the oil change until the system tells me to change it (like the owner's manual suggests ). Here's my question for you guys who actually work in the automotive industry: How accurate is the oil life monitoring system and how exactly does it work? I have a degree in mechanical engineering so I know how important it is to properly lubricate an engine.
Thanks!

*Upadate:* Read this post in its entirety.................you might learn something.

 

I am also a degreed mech eng. You are going to get a TON of responses on this thread from people who have no ******* clue what they're talking about. Only take advice from people who are wealthier than you, remember that. The majority of the people on this site are union or non-union blue collars who will only make $30-$40/hour (adjusted for inflation) for the rest of their life.

On the cobalt, the engine calculates oil life using an algorithym. Is its basically the cheapest and least complicated oil monitoring system on the market. It looks at RPM, miles, # of times you've gone WOT, # of heat cycles the engine has gone through, and spits out a % at the end. Some of the higher end cars actually use dielectric resistance as a method, such as BMW. They take their oil, send electricity through it, and measure the change in resistance. Obviously the more garbage, the higher the resistance. Some of the EVEN higher end cars acutally have full oil monitoring with the trivector technology, Im not going into that because chances are, you and noone you ever know in your life will be able to purchase such a high end vehicle. If youre worried about it, have your oil professionally tested. I change my oil every 5,000 miles with mobile one and have a full time tribologist that works for me. He basically tests oil for a living. There was ZERO change in the mobile 1 whether I changed it at 3,000 or 5,000 miles. This is a $35,000 oil analysis machine to boot....

 

I go by the OLM, mines at 5% right now BTW lol.

 

I go by what the DIC says and change it w/ about 10% left on the life meter ....
I frequently check my oil to make sure it's full and not brown!!!

 

while this is a great response, you're an idiot. you think that the amount of money you make dictates how much you know about cars? give me a break. you sound like a cocky, arrogant *******. if you left that first post paragraph out, you would have sounded smart, and helpful.

I make close to $100/hour on the weekends on top of my regular salary and commission. does that mean i'm a car god, and no one knows more than me? what a tool.

 

that is the most stupid thing ive ever read. i had to read it 4 or 5 times because it was so stupid i didnt think anyone would actually say something that was well for lack of better words, stupid.

ha ha obviously if this kid meant what he said id never listen to another word that came out of his mouth.

hahahahaha i still cant believe this came out of someone. wow im still in a bit of shock

 

i changed my oil at 3k with both Mobil 1 and RP. i'm going up to 7.5k and through 2 filters on Amsoil, maybe more but we'll see.

i'm not rich though i just change oil for a living.

 

you type faster than i do. this guy is a tool hahaha and not a bright one

 

Right you are.

I change my oil at around 3K and the OLMS usually reads in the low 50% range around that point.

My dad makes well over 10x more than what I make(I only made 9k last year part time) and he doesn't have a clue about cars.

 

yeah at 3k for me it says 47%

.......rev happy here

 

I like changing the oil filter every 3k and the oil at 6k. Saves a lot of money and we all know that Mobil 1 doesn't change that much in the extra 2k miles. It's the 10k mile changes that get a little worse

 

im in HS an have no job but i change mine @ 3000 miles

 

so ive got a question for all the people who think you can only listen to someone who makes more money than you do,

when your car breaks down, and your mechanic tells you that you need to replace something do you listen to him because he is a trained professional or do you not listen to him because you make more money than he does?

 

WTF is your problem, you sound like an absolute ********. This has to be the most ignorant post of the new year thus far. I met a guy who drove and lived in ragged out 80s Oldsmobiles, hadnt shaved or showered for days and could weld circles around anyone else Id ever met or seen and knew more about the design and function of internal combustion engines than 90% of the populace of this site combined!

Why dont you keep your caste based ******* ideals and comments to yourself next time.

LMFAO awesome, or what about when youre a multimillion dollar lawyer, athlete, actor, etc....what do you do when youre sick? go see Keanu Reeves?




The oil ife system in the Cobalt is fairly accurate at providing a percentage based life expectancy for the oil, provided two major conditions are met: A: you use high quality oil that meets or exceeds GM standards. and B: you dont drive in a dusty area. With that said there is no reason not to go by your OLM, change it when it gets down to single digits or every 11 months whichever comes first.

PS: Lewis, I am sure I am wrong since you make more than me and youre avatar says Mechanical Engineer, but dont trivector analyzers actually use dielectric analysis as a large portion of its actual data on the health of the oil? The laser optics are merely used to to locate and count particulater matter in the oil. The dielectric constant is arguably more important in the absence of excessive particulate matter.

Would you care to provide links to vehicle that use trivector based oil ife monitoring systems?

I wonder how youre full time tribologist would like to be referred to as a full time oil tester?

Maybe we should just call you you a guy who draws **** and does math problems?

 

Would like to see them too.

 

Give me some advice on how to break into the brisk 14s.

 

Lewis is teh fail
i talks like dis cuz only the wealthy iz smart

i dunno nothing

Seriously your a disgrace to any mechanical engineer. But dont take my word am only a EIT for civil/mechanical

 

I used to have a professor who said: "As an engineer, NEVER think that your better than ANYONE who works under you." He got his teaching position because he worked for 27 years as a machinist BEFORE he got an engineering degree.

btw.......where did you get your BSME? I went to Purdue.

 

This is wayy off topic but WTF is he looking at in his sig?

 

While I agree with Lewis on the Oil Life monitoring system, I have alwasy followed it changing my oil at about 10% and the filter at about 55%. I always send the oil off to get tested after each oil change to check the oil for how well it has stood up on its approx. 7,000 mile run as well as to see how the engine is holding up. My last lab test came back saying that the engine with 50,000 miles on it shows absolutely no signs of wear and the oil was still at 40% of its TBN and had virtually no contaminants in it; and that is with 7,000 miles on the oil.

I think what he is saying is that you should only take advice from people who are well educated in the area of the question. He used money to equate to education which is not necessarily true, however 75% of the time it is. For example, you wouldn't ask the secretary at the lawyers office for law advice, you would ask the lawyer if you expected to get a accurate response. If you want a question answered about how long oil will last, ask someone with a degree in chemistry that has knowledge of petroleum engineering.

 

the water...its called an artistic picture...down and bash his response but dont go just looking for stuff to make fun of and call out...

and lewis... your response was beyond harsh...i make 0 dollars an hour and i know more than alot of white-collar ******...

 

I wasn't bashing, I was asking if i was bashing it would be more like WTF is that blah blah looking at in his sig.

Take it as you want it was a simple question, if I wanted to bash in my first post I would have. In that if you don't see I asked for link to a car that would carry a system as he mentioned.

Did I ever say he was wrong or stupid or anything as other people mentioned?

Quit being a bodygaurd and go back to what you are doing.

Thanks for your answer. Let me rephrase so he can answer.

Lewis WTF are YOU looking at in your sig?

 

This is exactly how I meant for my comment to be taken....

 

whoa there...

i am not a "bodyguard" for lewis...as we have maybe spoken once and it was when i was thinking about M-E and he offered some advice....i have no preference whatsoever towards him...how he said what he said was definitely wrong...

 

Zero dollars an hour FTW

My degree isnt finished so I wont bother mentioning what letters it consists of, and I wont bother listing any of my actual hands on or other training or certifications because I dont matter since I make less than Lewis(do I?)

But let me say this, Ive worked with engineers who couldnt fix a sandwich, guys who are so into their degrees and their paychecks that they "earn" simply because they went to school and had connections, and Ive worked with "mere" mechanics who could solve mechanical problems faster than the sandwich engineer could ever hope to. I know this is the way our world works but dont ever assume someone knows less than you simply because of the amount of letters after your name or the quantity of pieces of paper that you have been awarded. An engineer who has little practical experience or hasnt ever been hands on with the real world is a worthless number pusher. The only people likely to disagree are said number pushing engineers.