Greetings audio fellows,
I readed very goods inputs in John's long preamp thread about oil grades and car engines.
What about the real agging of the oil in the diesel engines from our cars please.
My car manual says to purge engine oil every 20 000 kms or every two years.
What about synthetic oils as the 5W40 if I onlt drive 3000 kms a year ? Should I purge the oil's engine every year ? Why ? Humidity? EGR that dirsts the top of the engine faster ? Towns use ? More pollution from gaz exhaust? Etc...
Help me please debug the truth please in that particular case. Is it for marketing reason as buying oil or for enginnering true reasons?
Many thanks for your futures inputts
I readed very goods inputs in John's long preamp thread about oil grades and car engines.
What about the real agging of the oil in the diesel engines from our cars please.
My car manual says to purge engine oil every 20 000 kms or every two years.
What about synthetic oils as the 5W40 if I onlt drive 3000 kms a year ? Should I purge the oil's engine every year ? Why ? Humidity? EGR that dirsts the top of the engine faster ? Towns use ? More pollution from gaz exhaust? Etc...
Help me please debug the truth please in that particular case. Is it for marketing reason as buying oil or for enginnering true reasons?
Many thanks for your futures inputts
Well what I like to do with my car is change the oil before it goes completely black. I do not like waiting until the oil is completely fouled before changing it because that means my car ran with dirty oil and was subjected to more wear and tear than need be.
On MY car (99 miata), I have found that if I change the oil about every 3000 miles the oil that drains out is a really dark redish color. AKA its close to turning black.
I also don't play around with oil weights. I put in what the manufacturer recommends, and I recommend you do the same.
I don't play around too much with the quality of oil either. I buy what ever name brand oil is on sale or is otherwise cheaper. IMO buying oil that is half the price of the expensive stuff but doing oil changes twice as often will almost always yield better results.
Here is what I would suggest. Get your oil changed and then ever 1000 km crack the bolt on the oil pan just enough to let some oil drip out. Make a note of the color, then tighten the bolt back down. Keep repeating the process until you notice the oil is black or near black. From then on, I would change the oil at what ever that interval turns out to be.
On MY car (99 miata), I have found that if I change the oil about every 3000 miles the oil that drains out is a really dark redish color. AKA its close to turning black.
I also don't play around with oil weights. I put in what the manufacturer recommends, and I recommend you do the same.
I don't play around too much with the quality of oil either. I buy what ever name brand oil is on sale or is otherwise cheaper. IMO buying oil that is half the price of the expensive stuff but doing oil changes twice as often will almost always yield better results.
Here is what I would suggest. Get your oil changed and then ever 1000 km crack the bolt on the oil pan just enough to let some oil drip out. Make a note of the color, then tighten the bolt back down. Keep repeating the process until you notice the oil is black or near black. From then on, I would change the oil at what ever that interval turns out to be.
Thank you for your inputt.
The Miatta has a solid engine, it's near a no problem car from what I readed
, it worths to change oil more often, it became a collector car (at least I dunno with the brandnew model which has a slighty different motor from the readed reviews)!
I have a diesel engine and diesel powered engines have their oil being black in few kilometers (less than 1000 km), so not really an indication of real aging for my car.
Yep I use the 5w40 oil and the index given from constructor in my model car manual.
Question is : does time change oil quality and degrade diesel engines after one or two years when driving few kilometers per years as my yearly 3000 km ?
As the engine is in sealed circuit, does humidity apply as brakes fluid ?
When driving really few does an older oil becomes less efficient to lubrificate piston cylinders and so on when starting the engine ? I readed synthetic oil catchs less humidity than the old mineral oils!
Does the town driving a factor to change faster the engine oil (well a diesel engine is not running as fast as a fuel engine - Most of the time diesel cars break from the engine surrounding : gear, turbo, diesel pump, transmission).
I'm going to clean the EGR valve and the air admitting pipe (collector is unluckily to hard to remove without time as I have not a private garage) but I really wondering if yearly or every two years fresher oil is better for the top of the engine (common piezo injection ramp, admission valves, etc ?) My car is 140 000 kms and should break before 200 000 Km due to some others causes (turbo as said, diesel pump mainly but also gears box) and will costs much than purchase a second hand car with less kilometers.
The Miatta has a solid engine, it's near a no problem car from what I readed
, it worths to change oil more often, it became a collector car (at least I dunno with the brandnew model which has a slighty different motor from the readed reviews)!I have a diesel engine and diesel powered engines have their oil being black in few kilometers (less than 1000 km), so not really an indication of real aging for my car.
Yep I use the 5w40 oil and the index given from constructor in my model car manual.
Question is : does time change oil quality and degrade diesel engines after one or two years when driving few kilometers per years as my yearly 3000 km ?
As the engine is in sealed circuit, does humidity apply as brakes fluid ?
When driving really few does an older oil becomes less efficient to lubrificate piston cylinders and so on when starting the engine ? I readed synthetic oil catchs less humidity than the old mineral oils!
Does the town driving a factor to change faster the engine oil (well a diesel engine is not running as fast as a fuel engine - Most of the time diesel cars break from the engine surrounding : gear, turbo, diesel pump, transmission).
I'm going to clean the EGR valve and the air admitting pipe (collector is unluckily to hard to remove without time as I have not a private garage) but I really wondering if yearly or every two years fresher oil is better for the top of the engine (common piezo injection ramp, admission valves, etc ?) My car is 140 000 kms and should break before 200 000 Km due to some others causes (turbo as said, diesel pump mainly but also gears box) and will costs much than purchase a second hand car with less kilometers.
Having been mechanically inclined my entire life (personally/professionally)
I can unequivocally state (without ABX testing) that no internal combustion engine will suffer from oil that is too fresh.......just change it.
And if your way under mileage at 2 yrs and those miles were easy driving 3 yrs is not a stretch.......shell rotella t (Dino) or t6 (synthetic) are good diesel oils. (In the reco’ed vis of course)
I can unequivocally state (without ABX testing) that no internal combustion engine will suffer from oil that is too fresh.......just change it.
And if your way under mileage at 2 yrs and those miles were easy driving 3 yrs is not a stretch.......shell rotella t (Dino) or t6 (synthetic) are good diesel oils. (In the reco’ed vis of course)
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I take it your car does not have an oil life monitor system...if it does this is the best way of scheduling oil and filter changes. Otherwise follow the manufacturers recommended oil and filter service schedule and use an oil with an API service rating equal to or higher than the manufacturers recommendation. One caution on diesel oils, newer formulations designed for compatibility with aftertreatment systems and low sulfur diesel fuel are not necessarily backward compatible with older diesel engine technology.
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Thank you to both of you,
My car has a warning oil syst that lights wether the parameter comes first, time or kilometers since last purge following constructor recommendation. Anyway I change the oil filter eactime I change oil cause it costs almost nothing on my car model and it removes the 0,5 liters of the old oil.
My car has a warning oil syst that lights wether the parameter comes first, time or kilometers since last purge following constructor recommendation. Anyway I change the oil filter eactime I change oil cause it costs almost nothing on my car model and it removes the 0,5 liters of the old oil.
Everything you could ever want to know about oil is on this website(no relation!) A Review of Mineral and Synthetic Base Oils - Bob is the Oil Guy
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Do not use oil additives. If you want to clean the innards of your engine do it the proper way. Or do as an old school mec like me does. Drain the oil, add right amount of diesel instead of oil and run it on idle until its warm. Drain and change filter. Add new oil. If this sounds dodgy - than don't.
This was an old farmers trick before detergents and oil filters were common.....I would not recommend that today.
Not saying it wouldn’t work......just saying it might do more harm than good.
I have an 08 Audi A4 and a 05 911 997.1. The Audi requires a quart of oil a month. This is a known issue and says so in the manual (depends on driving style). Been using the recommended 0w40 synthetic for both. By the quart, it's around $9.50 to $10 a quart. Less for 5 quart quantity container.
I picked up 101 Projects for your 911 996/997 by Wayne Dempsey.
In it describes a test done in the 1990's on city cabs running for 60k miles. Each had a different grade of oil- traditional/standard motor oils and synthetic. They found that there was no discernible wear difference between synthetic and standard motor oil. They go on to say the increased performance of standard motor oil is due to the improved additives.
In the 911, due to a certain "flaw", I have to change the oil based more on time than distance. Should be done every 6 months.
It's a lot of motor oil, time and money. I'm torn between following the manufacturer's recommendations and realistic practicality.
Thing is, how much have synthetic oils improved since the 1990's?
Also my cars are from the early 2000 era. How much did parts materials change? How different are motor materials from a 1990's cab than a A4 B7 and 997.1? Can a cab due 0-60 in around 4 seconds? Who am I to question an MIT grad who been working on Porsche engines for years?
No clue. At least if I follow the recommended, can't say I didn't try.
I picked up 101 Projects for your 911 996/997 by Wayne Dempsey.
In it describes a test done in the 1990's on city cabs running for 60k miles. Each had a different grade of oil- traditional/standard motor oils and synthetic. They found that there was no discernible wear difference between synthetic and standard motor oil. They go on to say the increased performance of standard motor oil is due to the improved additives.
In the 911, due to a certain "flaw", I have to change the oil based more on time than distance. Should be done every 6 months.
It's a lot of motor oil, time and money. I'm torn between following the manufacturer's recommendations and realistic practicality.
Thing is, how much have synthetic oils improved since the 1990's?
Also my cars are from the early 2000 era. How much did parts materials change? How different are motor materials from a 1990's cab than a A4 B7 and 997.1? Can a cab due 0-60 in around 4 seconds? Who am I to question an MIT grad who been working on Porsche engines for years?
No clue. At least if I follow the recommended, can't say I didn't try.
Not really that ancient.
Depends on the engine and the one doing it. Note: run on idle. Only. Never rev it. If the engine takes harm of it, maybe the engine was not that good to begin with
?
Not really that ancient.
Depends on the engine and the one doing it. Note: run on idle. Only. Never rev it. If the engine takes harm of it, maybe the engine was not that good to begin with
I’ve done the same for swamped marine diesels but if that extreme a measure is needed today in a passenger vehicle your oil change intervals are much too long.
Funny thing my old dodge truck with a 360 v8 runs better on drain oil, fresh oil it burns almost a quart every tank full.......I noticed this when I started using the drain oil from my wife’s Tahoe, after about 3 quarts of drain oil it stopped using oil.
Sometimes dirty oil is better!
Well, so much to say, hard to know what to emphasize.
AFAIK changing oil more frequently does pay rewards, but you get into diminishing returns where you are wasting time and money. If you change your oil yourself I would recommend doing more frequently than 20kkm/2yrs.
Don't follow dated recommendations, modern high additive diesel oils are different enough to change old guidelines.
Oil is aged by shear-thinning, condensation, fuel contamination to name a few. That's why it's not just a marketing ploy to recommend frequent changes.
You can access a tremendous amount of information by Googling, there are hobbyists who pay for their own oil lab tests so you would only find that type of information in a forum or blog.
AFAIK changing oil more frequently does pay rewards, but you get into diminishing returns where you are wasting time and money. If you change your oil yourself I would recommend doing more frequently than 20kkm/2yrs.
Don't follow dated recommendations, modern high additive diesel oils are different enough to change old guidelines.
Oil is aged by shear-thinning, condensation, fuel contamination to name a few. That's why it's not just a marketing ploy to recommend frequent changes.
You can access a tremendous amount of information by Googling, there are hobbyists who pay for their own oil lab tests so you would only find that type of information in a forum or blog.
Yes it does my friend.......yes it does.
Are you familiar with the term ‘diminishing returns’ ?
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