Posted on 09/17/2010 12:02:53 PM PDT by Vigilanteman
From what I’ve read and seen of dissected oil filters, the Purolator Pure One is the one to buy.
I drive a Jeep Liberty, so a 10% increase in gas mileage would be 1.6 mpg, below the noise compared to how much stop-and-go driving I do on any particular tank.
So, to answer you question: I don't know.
If you REALLY want to be safe you should buy a new car every 3000 miles.
My older brother tells me he can remember in the 50’s dad had to buy new tires every 5,000 or so. Dad was a salesman.
Vehicles on hand:
1976 Chevy 454 1 ton dually w/ over 345,000 miles
1979 Buick wagon with Olds 403 engine & over 191,000 miles on it.
Oil gets changed at 3,000 or less. Oil & Air filters also. Cheapest thing I can do to get a very long life out of my vehicles. Auto parts store takes used oil.
There are three separate considerations for oil changes.
1) Is the condition of the base oil
2) Is the condition of the additives
3) Is the level of particulates/contaminates
Generally speaking, synthetics address #1. Synthetics tend to break down less at higher heat than conventional oils although most people who aren’t driving high performance vehicles don’t need the extra protection
#2 is dependent on the particular brand of oil and the additive package included
#3 depends on a lot of things. The environment in which you drive, and the condition of your engine being the main two. Dusty environments will lead to particulate contamination. Older, worn engines will have more metallic particulates, and may also contain more combustion contaminates, especially as the piston rings wear.
Broadly speaking, however, you don’t change your oil because of #1, you change it because of #2 and #3. Old oil still (genearally speaking) lubricates just fine, its just that it’s contaminated, and the additives (which do many things) have been broken down or used up.
One of my jobs to pay for college was a certified auto mechanic.
Stating that, 3000 for regular oil and 4000 to 5000 for full synthetic.
Using that formula my last van had 255,000 miles when I gave it to a newspaper delivery person (it is still running as a delivery van three years later). and my wife’s commuter car just rolled over 182,000. Neither burn more oil than what they did when new.
My current “new” van has only hit 80,000 miles so the jury is still out on that one.
every 3000 is still a whole lot cheaper than an engine rebuild
FRAM & AC DELCO are all I use.
In my lifetime- I probably have driven close to 1,000,000 miles on all my vehicles. Am now almost 71. Had first car at 17. A total of 10 vehicles, including my Chevy 1 ton 454 dually that tows horses & works very hard.
One of my sisters recently bought a late-model used Saturn SUV recently.
I was surprised to hear her tell me that it has a sensor that operates between the oil pan and the oil filter.
It monitors the oil level and its “purity” - which would vary depending on amount use and type of use over time.
When the oil becomes lower than some level the sensor is looking for, or the purity is less than some level the sensor is looking for, a “change the oil” idiot light on the dash lights up, when the engine is running.
I’m not that fond of Saturn’s myself and I don’t know how good its oil sensor system is; I just didn’t expect it from them.
$25 a change is cheap insurance.
>>> and trips short enough for the oil not to heat up. <<<
You were doing good until you got to this point.
1) The oil heats up to temperature within a minute. The cooling system then keeps it at a constant temp for the rest of the trip.
2) Oil is hydroscopic - it loves to absorb water. The water then reacts with the oil to form acids. When the oil is heated up, it helps drive the water back out of the oil. So long trips are better than short trips for your oil life.
GM has put oil change lights in a lot of cars, starting, I believe, with mid 80s Cadillacs and perhaps Corvettes of the same era.
I chatted online with a GM engineer awhile back and he was pretty proud of the algorithms they developed. It’s not just a mileage counter. Apparently they take into account all sorts of inputs from the ECM to determine how often the oil needs changed based on driving style. Only thing they couldn’t monitor when I talked to him was the amount of environmental particulates, so he suggested those in extreme dusty environments might want to change more often. IIRC, the algorithms erred on the conservative side but they did help stretch the change intervals if your driving style warranted it.
It’s been a few years. It would be interesting if they had actually developed some sort of particulate detector since then.
Might want to read the manual a bit more closely. That’s the ‘normal’ change interval, but I don’t know anyone who meets those specifications. Most people’s driving lands you squarely in the “severe service” category, which is less (and mentioned in the manual).
When I bought my last car, the dealer (MB) said the scheduled maintenance was 13,000 using Mobil One Extended. So I said that I should really do 7,500 and he said no 13,000. I compromise and do 10,000 as it’s easy to remember.
Even my European-born mechanic has switched to synthetics and now tells me 7,000 is fine on my other cars.
Hmmm...VW says 10,000mi/1yr. between oil changes for my new Jetta. Had the oil changed at the one year mark already, although it had less than 5,000 miles on it (first three years of regular maintenance are free).
No issues- last vehicles had 202K (Cherokee 4.0) and 203K (Grand Cherokee 5.2) miles when I sold them and neither was burning oil.
Can't tell what difference it makes far-far past 200K because I don't intend on ever keeping them that long. Bottom line- Even if there is some marginal benefit over a longer life of a motor, for most people it will make no damn difference because you will never keep the vehicle that long. At 200K I imagine I'm statistically probably already an oddity!
I agree-
All the lube places are pushing this nonsense.
The motors, the oil, and the fuel have come so far along that the 3K interval is BS. Even with a non-synthetic you’re fine past 3K. -IMHO
The "oil condition" is determined by an algorithm running in the powertrain controller that considers a bunch of operating factors and calculates remaining oil life.
When I used synthic I noticed the engine temp. gauge would go up to the thermostat temp. of about 192 degrees. then drop back 15-20 deg. whenn the t-stat opened and remain there unless you put a heavy load on the engine. With regular oil, the temp would go up to 192 and remain there. I reasoned that if the temp. stopped falling back with synthetic oil, then it was losing it’s quality.
BMW recommends every 15,000. Haven't had a problem yet.
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