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Oil Change, obsessive? or just OCD?

So I thought I would just throw out my oil change procedure just to see if there are any like minded auto fanatics out there that use the same oil change thought process as I do or maybe even a better way to do it. So here it goes. A 2005 Chevrolet Corvette with an LS2 motor with 95K miles on the clock. I change my oil at evry 3K miles. I will NEVER be caught waiting until 7500 miles, or 10K miles, or 20K miles or changing my oil once a year nonsense that you see in commercials. The oil viscosity tech may have changed but we have yet to discover "self cleaning" oils.

I started a bit differently this time by letting the car sit for a week without the motor turning over at all to let everything settle to the oil pan. I haven't done this before because it really isn't practical as this is a daily driver.

So I get the car up on ramps without starting the motor. I set the parking brake and pull the oil plug and oil filter and a thick black dirty oil pours from the oil pan drain and you can feel the micro carbon grit in the dirty fluid. The DIC read "37% oil life" after 3K miles this oil change when it normally reads "50% oil life" in previous oil changes. I change the oil at 3K miles regardless of what GM or my DIC demands.

Next step is to replace the oil plug, screw on an inexpensive STP oil filter, and add 6 quarts of basic STP 5W-30 oil, start the engine and let it idle until the oil comes up to temperature and then shut the car off to let the "first oil change" as we will call it settle to the oil pan once again.

I again jack up the car, crawl under to once again remove the oil plug, oil filter, and wait until the last drop of oil falls from the oil drain. This time the oil comes out cleaner than the old oil and even cleaner than in past "first oil changes" and i think its because the old oil in the car got the opportunity to settle to the bottom of the pan for a week.

So last step in my oil change process is to button the bottom of the engine back up and this time add a top of the line oil filter and refill the crankcase with Mobil 1 5W-30 synthetic as the manufacturer recommends, put the car back on the ground, fire it up, let it get to temperature while looking for leaks, shut it off and then read the dipstick. I then slide a piece of clean cardboard under the car and come back in an hour and look for a leak to show up on the cardboard.

Is that all too much? is it crazy? is it obsessive? is it OCD? or are there OTHER car fanatics out there that have a similar procedure? a similar love for the care of their autos?

Do you have any similar oil change processes or ideas you want to share? and opinions on this procedure? my madness?

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360, the only concern I have with what you are doing lies in something you didn't specifically state. What type of oil are you using for oil change #1?  If memory serves, the LS motors, particularly the Corvette motors all require synthetic oils. So I would make certain not to use a cheap conventional oil while trying to flush the remaining dirty synthetic oil out in change #1. I would try to find the least expensive synthetic or at the very least a synthetic blend. 

My reasoning is this, synthetic oils are for very tight tolerance motors, like the LS, modern Hemis, and Coyotes. So why risk possible cross contamination (and worst case - engine damage) between a conventional and a synthetic?  

Now if I am off base here and you aren't doing this, I have no concerns.

Edited by Frosty
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10 hours ago, Frosty said:

360, the only concern I have with what you are doing lies in something you didn't specifically state. What type of oil are you using for oil change #1?  If memory serves, the LS motors, particularly the Corvette motors all require synthetic oils. So I would make certain not to use a cheap conventional oil while trying to flush the remaining dirty synthetic oil out in change #1. I would try to find the least expensive synthetic or at the very least a synthetic blend. 

My reasoning is this, synthetic oils are for very tight tolerance motors, like the LS, modern Hemis, and Coyotes. So why risk possible cross contamination (and worst case - engine damage) between a conventional and a synthetic?  

Now if I am off base here and you aren't doing this, I have no concerns.

"What happens when you mix synthetic and conventional oil?"

According to Mobil Oil, it should be fine to mix oils. This manufacturer states it would be unlikely anything bad would happen, such as a gel-forming from an interaction of the chemicals (a common fear), because the oils are compatible with each other. In fact, many oils are a blend of natural and synthetic oils. Any SAE rated motor oil can be mixed with any other with no problems. That’s one of the requirements to get a SAE rating.

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Posted (edited)
On 9/8/2018 at 2:53 PM, 360Rocket said:

Oil Change, obsessive? or just OCD?

So I thought I would just throw out my oil change procedure just to see if there are any like minded auto fanatics out there that use the same oil change thought process as I do or maybe even a better way to do it. So here it goes. A 2005 Chevrolet Corvette with an LS2 motor with 95K miles on the clock. I change my oil at evry 3K miles. I will NEVER be caught waiting until 7500 miles, or 10K miles, or 20K miles or changing my oil once a year nonsense that you see in commercials. The oil viscosity tech may have changed but we have yet to discover "self cleaning" oils.

I started a bit differently this time by letting the car sit for a week without the motor turning over at all to let everything settle to the oil pan. I haven't done this before because it really isn't practical as this is a daily driver.

So I get the car up on ramps without starting the motor. I set the parking brake and pull the oil plug and oil filter and a thick black dirty oil pours from the oil pan drain and you can feel the micro carbon grit in the dirty fluid. The DIC read "37% oil life" after 3K miles this oil change when it normally reads "50% oil life" in previous oil changes. I change the oil at 3K miles regardless of what GM or my DIC demands.

Next step is to replace the oil plug, screw on an inexpensive STP oil filter, and add 6 quarts of basic STP 5W-30 oil, start the engine and let it idle until the oil comes up to temperature and then shut the car off to let the "first oil change" as we will call it settle to the oil pan once again.

I again jack up the car, crawl under to once again remove the oil plug, oil filter, and wait until the last drop of oil falls from the oil drain. This time the oil comes out cleaner than the old oil and even cleaner than in past "first oil changes" and i think its because the old oil in the car got the opportunity to settle to the bottom of the pan for a week.

So last step in my oil change process is to button the bottom of the engine back up and this time add a top of the line oil filter and refill the crankcase with Mobil 1 5W-30 synthetic as the manufacturer recommends, put the car back on the ground, fire it up, let it get to temperature while looking for leaks, shut it off and then read the dipstick. I then slide a piece of clean cardboard under the car and come back in an hour and look for a leak to show up on the cardboard.

Is that all too much? is it crazy? is it obsessive? is it OCD? or are there OTHER car fanatics out there that have a similar procedure? a similar love for the care of their autos?

Do you have any similar oil change processes or ideas you want to share? and opinions on this procedure? my madness?

 

On 9/10/2018 at 8:34 AM, Frosty said:

360, the only concern I have with what you are doing lies in something you didn't specifically state. What type of oil are you using for oil change #1?  If memory serves, the LS motors, particularly the Corvette motors all require synthetic oils. So I would make certain not to use a cheap conventional oil while trying to flush the remaining dirty synthetic oil out in change #1. I would try to find the least expensive synthetic or at the very least a synthetic blend. 

My reasoning is this, synthetic oils are for very tight tolerance motors, like the LS, modern Hemis, and Coyotes. So why risk possible cross contamination (and worst case - engine damage) between a conventional and a synthetic?  

Now if I am off base here and you aren't doing this, I have no concerns.

360, I’m just catching up after being out of touch for a while, but you’re not OCD, you’re quite wise! I do very similar, minus the cardboard though. Flushing an engine with a new filter and fresh oil is the ultimate way in which to effectively clean, flush and rejuvenate mechanical parts as well as seals. While moving all that unwanted debris out of an engine. 

You hit the nail on the head when you noted that synthetic or not the oil still gets dirty. I’ve commented on the subject before on this site! Synthetic oil serves only one purpose, that is to maintain a constant viscosity! Synthetic oil is a shear stable product, that’s it! Everything else is the same as conventional oil, providing they have the same additive package. 

Conventional oil holds it’s viscosity for about 2000 to 3500 miles depending on oil quality and additive package. At some point shear starts to take hold and the first thing that happens is the oil starts to thin than after a short time it begins to thicken.

Frosty mentions the engine specs of the Corvette requiring synthetic oil! The reason for that on that engine and engines like it are bearing clearances and other contact parts. One experiment I ran at work was to show the effect of increasingly smaller gaps in bearing tolerances and their effect on oil viscosity especially with soot. This phenomenon can drastically reduce viscosity locally in the bearing journal as opposed to the bulk viscosity of the oil. This occurs because the debris hits/rubs together creating friction/heat elevating the local temperature thus lowering viscosity.

When we would run a field test on a specific oil chemistry and then run the next test on that motor we always flushed it twice! And we would run the engine for 15 to 20 minutes after it reached temperature. So the only real change you could make is to run the motor a little longer on the flush. I could go in to more detail if you want, but I think you see the point!

The only additional thing I would say is, a synthetic oil will still oxidize, it still is contaminated with acid (tan), still becomes fuel diluted, still becomes heat stressed which consumes the additive package. So at 3000 or 4000 miles everything that the conventional oil has been through so has the synthetic and the only difference between the two will be the viscosity! Fact, 90 percent of engine failures from oil related issues are from the additive package failure, not viscosity!

Edited by Last Indian
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In other news, came across this filter on one of my stops today that came out of a Toyota Camry with 147K miles on it. This could possibly be the original filter.


IMG_1918_zpsv0ikjelr.jpg

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