So much bad info here and urban legend... "MOTOR" oil does not break down???????????I guess no one ever heard of thermal breakdown... Shear...or reduced particle suspension cause by thermal breakdown, lubricity, acidity and viscosity depletion.

"Use the Freekin OIL Life Monitor" it took many months of time and research and thousands of dollars to develop...specifically for YOUR car

or you can listen to Grand pop and what he did in the fifties with his Buick Roadmaster, when engine life was around 60,000 miles.

 

My 98 C5 and 01 Grand Prix get oil changes by the indicator. Oil analysis tells me the oil still has useable life when I do change it!!

Ron ...

 

GM's oil life moniter is programmed specificly for Mobil 1 synthetic which is by far not the best on the market. We are talking about using a superior oil that helps your engine lubricate better and resists breakdown more effectively (not prevent breakdown) therefore prolonging engine life better than cheaper synthetics with additives even if you do change the oil every 3k miles. Its like using nitromethane instead of gasoline and arguing, "why reprogram the ECU when GM spent so much time getting it right". BTW, my grandpa taught me that...

 

I have no doubts they can make an oil that will last that long.

My question is, who in their right mind would want to go that long without looking at thier oil?

 

How much is this Mobil oil 5000, 7500, 15000?

 

John, I think the 15k is about $5.25 at walmart.

 

Those of you who change oil at 3k are wasting oil, time and money. And no you are not buying cheap engine insurance. The new cars, new engines, new computers, and new oils are much better than in the old days. I am 61, I still have my first car a 68 Camaro with a 327. That oil was dirty way before 3k. The 97 Camaro LT1 I changed at 5k. It was the fastest Z-28 at the track, got 30mpg on the road, and at 84,000when I sold it was using very little oil. I will follow the computer on my Vette, daily driver, but will give in and have been changing at 25%.
OLD HABITS of 3k are hard to let go of. The dealers, and petro companys love you 3k guys. The sad part is you are not helping your engine just the petro companys.

 

The owners manual even says up to 7500 miles on an oil change. Mobil 1 only. I think everyone is paranoid with the oil change question. This has been the most talked about issue thread on this forum for no apparent reason at all. Just use the DIC and reset it at oil changes.. Easy as pie. The DIC will tell you when you are down to 10% of usefull life

 

Why not trust the DIC?

 

I may just put a barrel of oil in the hatch of my coupe. That way I can have it stream continuously through my engine and drip down to the road (not an environmentalist). My oil will only go through one time before getting tossed.

I will also replace my tires when they get dirty.

 

Dang E-T, you hit it exactly. I can remember helping my dad change the oil in his 1940 Roadmaster. He did it every 1000 miles. There was no filters in those days and he had it rebuilt, rings bearings and a valve job, at 50K. During the WWII, he bought Sunoco 30 weight that came in cardboard cans as metal went to the war effort.

Technology of engines and oils has change dramatically since then, but Old Wives Tales die hard.

 

I personally don't buy it. Like said before, it isn't that it really goes bad but it gets contaminated.

 

All you have to buy is a comprehensive oil test for a few bucks it tells all. Done, end of guessing.

It feels good to change it. I feel it is running better and will last longer even if it is a cement mixer That's part of the problem.

 

It seems that this topic will never die. It's also particularly sad to see people who proudly -- and rightly so -- talk about the technological marvels of their car then repeat the hackneyed "cheap insurance" non sequitur. Equally as sad is that it seems to be a case of an emotional argument versus a logical one so it seems that we're doomed to go around in circles.

Why is it so hard to understand that technology, oil and in general, has progressed from the days of old? Just because our grandparents changed their oil at 3000 miles doesn't mean we need to.

Do those that refuse to trust the oil life indicator also totally deactivate the ABS, traction control, active handling, climate controls, air bags and so on. Do you also refuse to even drive the car because you don't trust the fact that so many operations are controlled by computer? Of course not. Yet the particular function to accommodate the fact no oil ever was always good to 2999 miles then suddenly went "bad" at 3000 seems to cause angst to so many.

There was a time when the general case of changing your oil at around 3000 miles was probably a reasonable thing to do. However, we've moved on. Man has now gone into space, the computer mouse has been invented, we no longer use punch cards and paper tape for computer input, Random Access Memory is everywhere, hand-held calculators have been invented, we now have computers that are even smaller and dwarf the capabilities of even the biggest of some decades ago and, of course, we now have have the Internet.

Oil technology has improved too.

Why is that so hard to believe?

 

I can remember the advertisements for Kendall "The 2000 mile oil", yikes! There were those who said then that they were not going to ruin their engine by going 2000 miles before changing the oil in their vehicle.
Guess what, engines were not ruined.
Then people started going 3000 miles before changing, WHAT WERE THEY THINKING? Now, since the early 90s, most manufacturers began going to 7500 mile recommended oil changes, and 15000 mile recommended changes are now upon us. The push behind this was enviromental impact, lessening the crude oil requirements for motor oils and fuels, and reducing the waste oil impact was a goal that the engineers faced, and met. The proliferation of synthetic oils helped reduce the need for dino motor oils, but the waste product remains regardless of type of oil used. Therefore the best way to reduce the waste oil product was to develop longer intervals. With the introduction of electronic / computer controlled fuel delivery, spark control and leaning of the fuel ratios, the old problem of fuel washing of the cylinders, and the resulting oil contamination was greatly reduced.
How many here remember pulling the dip stick and being able to smell raw gasoline in the oil, or lighting the oil on the dip stick? I doubt if anybody is having that problem in today's engines. Additionally, with higher running temps, moisture is usually boiled off with a drive to work every day, as long as the distance is great enough to allow the engine to reach full operating temperature. Because of the reduced moisture, acids are reduced and therefore the oil life becomes much greater than that of 40 years ago. Now there may be those out there who do need to change the oil and filter more often, but for probably 95% of us, we can go with the oil life monitor as our guide, note I said GUIDE.
So it all really boils down to individual preferance. Technically speaking, those who are changing their oil and filter at 3000 miles are doing so because they feel they need to, that's their peace of mind. For those who follow the oil life monitor, that to me is good sense, and as we already know, it's recommended in the owners manual. For those who track their cars, my guess is they probably are using some sort of outsourced oil life monitoring program, and are changing their oil often anyway. So that's my two cents worth, and a look back on changing times.

zo6vettepilot

 

That's what TBN (Total Base Number) is indicating, the oils ability to neutralize acids. At 3K miles it is practically new unless there is a mechanical problem with the motor (such as an internal coolant leak or something).

An oil analysis, done by Terry Dyson, will provide much information on how your oil and motor are doing.

 

I am not so sure I buy the "oil analysis tells" all story anymore. It seem slike some people do an analysis with X oil and then compare it to Y oil and see which has less heavy metal in it. The theory is that the one with the least metal is causing the engine to "wear" less. The only problem with that is that some oils don't do as good of a job carrying metals in suspension. Unfortunately an oil that does a lousy job of carrying particles in suspension will be judged as a great oil.
I'm also not so sure TBN numbers mean much as they keep changing the standard.

 

Changing oils before 3000 miles is a false insurance policy and in many cases will be a retro grade step for the engine life.
I have been in the oil business for over 20 years. In the days when I worked for Exxon R&D on engine lube oils, we tested oils in many bench engines which ran at loads and conditions way beyond that of the corvette engine, which is a relatively low-powered, lazy big engine that carries a lot of lube oil in its crankase.

Fresh oil is not at its optimum performance until a couple of thousand miles under its belt.
Very few of the Lube oils components will have had a chance to get working in the first few thousand miles. The combination of heat and pressure is the essence to the antiwear additives in the lube to start depositing in the surfaces they are designed to protect. The viscosity modifiers are designed to take their time to shear down and become effective products.

For that reason folow the GM oil life indicator or the handbook. The additive companies spend million developing products to meet the manufacturers needs. In europe oil changes for many high performance vehicles is set at 17,000 miles.

 

Bingo!
The last time this was brought up it was met with a lot of derision by the 3000 mile guys. I have read the SAE paper on this pointing out oils are at their best after several thousand miles. Unfortunately the article was on paper and it wasn't mine so I can't lay my hands on it. But changing oil at early intervals seems to be counterproductive.

 

I put 5-7 thousand miles on my car a year (7-8 months). I use the amsoil long life and just change the filter at 3000 miles and change the oil when it comes out of hibernation every spring. I use the 30000 mile amsoil in my 98 GMC pick-up with the vortec 350. I change the oil every 20000 miles and the filter every 5000. Thats got 105000 miles on it and runs like new. I really like the amsoil products. All my motors have it, the Harleys, the truck has the tranny, transfer case, and diffs. and motor. the vette has the 6-spd, motor and diff. even my 73 formula 400 4-spd has all amsoil products.