Engine Oil/Oil Changes Myth and Facts Thread
 

I thought I'd try and start something here since this is an automotive site. There isn't much debate on this site about oil and oil changes, whether people should use "this" weight and "that" weight or oil changes should be done every "5,000km" or "10,000km". I realized that even after years and decades of automotive discussions, different "words" and "recommendations" are still being thrown around and a lot of people are getting different(wrong) information. When I say a lot of people, I mean "enthusiast" , consumers and technicians/mechanics.

I would like to see what information and knowledge people have gathered about oil changes and the oils they use. Questions they have about it and using this thread as a way of throwing out the myths and getting all the proper facts that many others may find useful and interesting.

This should be a fun and long discussion/debate! :thumbsup:

(I know there's some grammatical errors, mods can fix them!)

for synthetic i go every 8,000 km's, or one year.

Personally I change it every 5000km, but I use dino oil and cheap filters.

Average commercial transport truck at my work goes from 20,000km to 60,000km on a oil change :damn:. Mind you the oil gets sampled and sent to a lab between changes.

this is going to be hard, as different engines/driving conditions require different weights of oil, different applications require different oil change intervals.

Why is there debate? Just trust the manufacturers' recommendations.

It was a shock when our family went from domestic (5000km) to German (15000km). But hey, if the manual and the dealer both say it's good enough.. good enough for me. Their engineers aren't stupid. Neither are their lawyers.

Maybe I'm just being new school, but with all the improvements in oil technology over the years, that 5000km limit is simply obsolete if you're going synthetic imo. Sure you can change it more often if you want; companies like Quaker and Mobil and Castrol thank you for your business. :)

Same deal with the weights. Just go with whatever the service bulletins/manuals suggest. Why mess with it?

Every 5000km with Mobil1 10w30 + oem filter

Not if you own a BMW. At least, not if you want to keep it in running condition.

BMW recommends 25,000km oil changes... sure, it's probably fine after 25,000km, but do you really want to risk it? That's especially insane for people who only drive their BMW as a "summer" or "weekend" car. They could go 3-4 years between oil changes.

Strangely enough, BMW changed their oil change interval to 25,000km around the same time they began offering free maintenance on all of their vehicles...


(*Edit: I remember reading somewhere they have revised the recommended oil change interval. Even if this is true, the 25,000km recommended interval was in place for many years. This is why some anal people caution against buying used late-model BMW's that do not come with service records as they could have run 25,000km+ without an oil change).

supposedly the BMW thing is because they have 6-7L or something compared to the traditional japanese import having 4-5L, so it "lasts" longer", i remember someone with an e92 telling me the manual SAYS 15,000km.

I change mine every 8-10k (depending how hard i've been on it) with regular... not that I beat on it, she's my daily anyways... OE/OE replacement filters, whatever works and isn't that paper thin fram stuff...

Judging (and having seen tons of oil) my own oil, it's still quite clean as it comes out, so it's literally a gigantic waste to have to change it... 2x-3x/year for me.

Also use the regular pennzoil stuff... nice and thick.

I thought it was xx,xxx km OR 1 year, whichever one comes first. But with that said, synthetic oil doesn't just magically go bad. This ain't dino oil. Usually the oil takes a few months just to get from the lab/factory to the store shelf, then who knows how long it sits there or in some guy's garage before getting poured into an engine. It's kind of like food. Milk is the only food I can think of that actually goes bad on the expiry date. (yes, I eat expired food all the time, haven't died yet. :D)

MB increased their service intervals to 15,000 in 1998, then 20,000 in 2005. The funny part is that these changes happened without developing new engines. Not sure about other makers but MB only really changed the list of recommended oil, and in some cases, changed the material in the filter. There is much talk on the MB forums of people who increased their service interval simply by getting the "higher" grade of oil local and having the new filters (not available in North America) shipped in from funky places like South Africa.

I remember my SA at the dealer mentioning that the oil can actually easily go 25,000km+, but most of the customers are "old school" and couldn't handle the sudden jump, so they had to phase it in over the years. :lol I remember my dad freaking and driving down to the dealership, where the SA had to show him the official MB bulletin on paper.

i think it depends on the car
on my corolla i do it generally every 5000KM ...
but on the 240
i was on it every 2500 to 3000KMs

was using royal purple for the longest time..and cheap CDN tire stuff for the corolla

royal purple's so "thin" i'd think you'd be best off changing it within 2-3000km anyways XD

i change every 6k/3 months, mobil 1....
i've seen first hand what the lack of oil changes can do...engine sludge/noise/blown motors etc.

would you do that if you drove hard during a certain period?

same thing for ppl who go to the track, they usually change out the oil after that.

I drove my car pretty hard recently, its only been 3000-3500km and im feeling bad already....feel like i need to change out the motul 8100 lol

6k/ mobil1-syntec 5w20 grade..
oil filter.. either OEM or NAPA.

I made a post a long time ago I feel might be worth a repost. And yes, there is no debate. Let me dig it up:



The 5,000km oil change is an absolute myth, perpetuated by companies like Jiffy Lube. (How else are they going to make their money from you?)

Modern cars and modern oils can go much longer. Just as how car tech has improved since the 70s, so has oil technology. For example, many new cars are equipped with an oil life monitor, which recommend oil changes that are far longer than 5,000km.

It's hard to believe, but the color of the oil has nothing to do with its remaining life and additive package.

One way to check is to do a Used Oil Analysis. (Collect some on the next drain with the free kit you can order from their website), then send it to http://www.blackstone-labs.com.

You'll get a report like this, and you can determine the ideal oil interval for your car.


http://www.jeffgoji.org/D90803.jpg
Amsoil 10W30 - 16,000km. 04 Mazdaspeed MX5, 1.8 turbo


Need more proof? Check out this guy running Amsoil 0w30 with a bypass filter and prelube pump in his S2000. 30,726 miles on the oil! That almost 50,000km!!

http://img.photobucket.com/albums/v7...44/9-08UOA.jpg


Things to look for when analysing the data.

-TBN # still exists.
-Oil viscosity are still within the specs as SAE has outlined.

http://www.bobistheoilguy.com/images/visc.jpg

So for oils like 5w30 or 10w30, 30 represents a range of 9.30-12.49 CsT or Centistokes.


Things to realize.
1. Oil color is NOT a good indication of Total Base Number (TBN), or oil life.

2. 5,000km oil change is unnecessary and is a waste of money and oil resources. (In MOST cases. If I drove an engine known for fuel dilution solely in the city, exclusively all short trips, say 1km each, then perhaps I would be a good candidate for 5k oil change interval) Another situation is perhaps if I drove a Mazdaspeed3, or GTI, where the engines have been know to shear the oil out of viscosity a little faster than other engines.

3. Oil change interval is heavily dependent on car and driving conditions. If you drive highway frequently you can extend your oil change intervals, because it takes roughly 15-20km for oil to reach full operating temperature. At this temp, you'll be able to burn off the fuel dilution.

Frequent short trips = shorter oil change interval.

By most standards, take an average Corolla or Civic. They can easily go 8,000km on regular conventional oil, even longer on a synthetic fluid.

Personally, I run 12,000km OCI in my RSX with a quality synthetic and sleep well at night. (Confirmed with some used oil analyses). I would have no problem extending out to 16,000km if I had to, the 4,000km is just a nice safety margin. In fact my last oil change I did had 17,000km. I drive 95% highway.

i change my oil around 7k with penzoil 5w30 syn with oem filter. My oil becomes quite dark after the 5k mark.
Posted via RS Mobile

Having an older car/engine, I change every 5000ish with synthetic. It only costs me roughly $30 to do my oil change with synthetic so I would rather do it a little more often than needed to just be on the safe side and have peace of mind.

It's tough to get over that psychological barrier. If you have an older car and changing every 5,000, you might as well use dino. Using synthetic for that little time you aren't receiving any of the benefits it can offer.

Might as well save a bit of money by switching to dino.

lol i remember that thread

u are like the king of lubricants
:haha::thumbsup:



PS

now if you semi race your car, stuck in traffic, or got a heavy foot...i would imaging you would finally say change it more frequently. FOr the s2k, with 50,000km until oil change i think that is absolutely crazy. first of all it redlines at 9000rpm, and Vtec engines are known to burn oil especially under heavy load or high rpm

There is no debate.

For 99% of people, just follow the manufacturer's recommendation or the Oil Life Monitor. They are written by tribologists (look that up) and engineers far smarter than you, who designed the engine. They understand what they are doing.

For enthusiasts, you can get the UOA's done by understanding the condition of the oil, you can make an informed decision about running a longer interval than the recommended. What? Doesn't that contradict what I just said with following the recommendations? Those recommendations are written to cover a wide range or circumstances and driving conditions which most people fall in. If you understand where you stand in terms of driving conditions, oil selection, you can override their recommendation with something you know they would have personally recommended for your style of driving.

If I had to guess, most car manufacturers would love to write different oil change intervals, perhaps even different viscosities for different situations (ie, if your S2000 goes on track all the time), but people just simply can't handle that.

Shit, it's tough enough just to get people to change their oil. I've talked to some women that are like "WTF you need to do oil change? I never knew that?".. BRAND NEW CARS they have. Another reason I would never buy "lady-driven" :).

As crazy as it sounds.. it the oil manages to

1. Stay in the correct viscosity range and not shear out of grade
2. TBN / TAN numbers stay above zero (Base number)
3. Oil levels are fine
4. Insoluble filtration is sufficient, (would involve changing filters sooner than oil
5. Burnt off oil is topped off


What's the problem? But yes, I agree with you. Different situations warrant different oil 'prescriptions'. For the S2K owner that had the bypass system installed, clearly the combo is working well for him. He probably does exclusively highway.

Mercedes recommends 1yr or 15000 kms, whichever comes first.

Does BMW give the same advice? It seems you don't even know what the current recommended BMW interval is, and you're just bitchin to bitch.

If you really wanted to be on the safe side, you'd get your oil tested for $30 rather than throw away $30 changing oil when you might not need to.

my jeep is currently getting mopar 15w-40, i'm going to switch back to 5w-30 in my next change. Because its an older car with some mileage on it. I make the intervals every 3000-4000kms. My BMW gets Lubro Moly 5w-40 Synthetic. When driven regularly i make my oil change intervals every 10,000kms. I have opened the valve cover, rebuilt the engine, opened the oil pan, and it looks very very clean. It also does not consume any oil. This is why i like this oil.

Eurocars often have special oil requirements, where the oils have passed certifications not required by other manufacturers..

If I recall correctly newer BMWs need to use an ACEA A3/B4 oil maybe need C3 as well. It will need either a LL01 or LL04 rating;he needs to look in the owner's manual.

Another example is the RDX with is boosted engine. The requirements are synthetic that passes the HTO-06 deposit spec. Would be a bad idea not to follow that.