Oil change recommendations?

[whatthe]

I've seen some long term tests with Amsoil and Mobil 1 showing the oil was still good at 12-15k miles. There was a guy with a Camaro that sent the samples in at regular intervals even.

If you keep the oil in, just change the filter every 3k miles and you should be fine. The scariest thing about long interval oil changes for me is how the filtration abilities drop off over time if you don't change the filter. This will depend on what type of filter (i.e. depth type don't clog up quite as bad over time, but don't as high filtration capabilities early on).

I ran Amsoil to 20,000kms in one of my GTs years ago. The bearings looked brand new at 225,000kms after taking the engine apart to do some head work for turbo.

For Dino oil, I prefer Castrol.

If you do some google searching, you'll come accross lots of oil filter studies and oil studies to reference.

[nascarnation]

Originally Posted by Krieg

Have you noticed much of a FE improvement since the switch?

I don't have good mpg data prior to the 5W20 oil, although it's been in the family for all 133,000 miles, mostly driven by my kids who have grown up and moved on to their own cars so it's back to me.

Personally I would be very surprised if 5W20 made a difference big enough to measure accurately without a chassis dyno and controlled environment.

The last 8 tanks (approx 330 miles each) have ranged from 33 to 36 mpg (it's an automatic). Using the AC is a much bigger variable on FE for a small engine car I believe.
Back in May there were days when I used no AC, then in June, AC on the way from work, now in July AC both morning and afternoon.

I always cringe when I see somebody on the net write "I put in XXX oil and got 2 mpg more"
I guarantee that any auto company would do that tomorrow if they could prove it on the EPA test.

[Krieg]

Ummmmm.... why do you think that Honda and Ford use 20 weight oil? Mileage and emissions. ULEV status is in part due to 20 weight oil.

Honda does make compromises in order to get that awesome gas mileage. 20 weight oil is one compromise.

[Krieg]

You know, the first couple of oil changes on my Acura Integra, driving out of the oil change place, the car felt stronger.

I don't doubt that switching to 20 weight oil makes a measurable but very small difference to fuel economy. 2 mpg sounds high, though.

[Bror Jace]

As oil is used by an internal combustion engine, it picks up wear debris, unspent fuel and other contaminants (dirt in the air) and loses it's ability to lubricate. When tested, it's coefficient of friction begins to rise.

So, running oil an extra thousand miles or two may hurt your fuel economy (along with promoting engine wear).

[rjacob]

Okay, I took may car to Honda this morning and had the oil changed. I asked the guy about what kind of oil they use, and he said Mobil. I asked about synthetic oil, and he said they don't recommend them. He said they have them for one or two cars that are supposed to use them (he thought the S2000). But he said for most cars, it's just a waste of money. I notice on the invoice they used 5W20 oil.

One thing they did though was to let air out of my tires. I had them at 38psi cold pressure. Now I have to ecoinflate them back 38psi (AAA says hyperinflating your tires is bad, so I ecoinflate them).

[IndyIan]

I'm not an engine expert but FWIW.
If you are pulse and gliding using big throttle openings and low rpm you are loading the bearings in your engine more than the average person. Also oil pressure at low rpms can be lower than at "normal" rpms. Plus if you are going to thinner oil that is less able to keep bearing surfaces apart you might have a recipe for trouble. You are creating the toughest environment for the oil to work at.
Also the first number in oil weight tends to be the base oil weight and the second number is achieved through additives which can break down leaving you basically running with the base oils weight. So your 0W20 may be just 0W0 after some amount of miles.

So 0W20 oil run for a many miles at high load, low rpm situations may result in scuffing a bearing which could be a career ending injury for your engine.

I second the oil analysis to find out for sure how the oil is doing over a longer change interval, just to be safe because you'd have to save alot of money on gas and oil changes to pay for any type of oil related engine work.

Ian

[jonr]

Believe it or not, engine wear and friction goes up when you first change the oil. So you don't want to change it too often.

Various studies show this, but this is the only one I find right now.

Valvetrain Friction and Wear Performance with Fresh and Used Low-Phosphorous Engine Oils - Tribology Transactions

Re 0w20 oil, why not give some room for degradation and use 0w30?

[othergames]

Most engines, when the oil is changed at reasonable intervals, will outlast the other parts of the car. This is getting to be like the "eggs are good for you/eggs are bad for you" argument. An apple a day keeps the doctor away, but eat too many and you'll get stomach or colon cancer.

Change your oil to extend the life of your engine, or change it if you want to damage it.

[nascarnation]

Originally Posted by othergames

Most engines, when the oil is changed at reasonable intervals, will outlast the other parts of the car.

excellent observation
but remember there are other forums where 20,000 OCD afflicted folks argue argue over parts per million results from their oil analysis.............

[whitevette]

Hi, all !
I have learned recently the EPA has decreed the zinc content of auto motor oils must go...due to the poisoning of cat. elements ( ye ol' lead in gasoline argument, remember?). This zinc compound ( zinc di-something) is an EP (extreme pressure) additive ; without it, aftermarket cam grinders are noting scuffing and scoring of lifter/ cam lobe interfaces...they are "upset"!
Have you noticed the oil ads on TV, lately? They no longer tout "anti-friction" qualities...but have emphasized "cleaning abilities". Like...Clean engines dying early is preferable to "dirty" old-timers, yes?
There IS a way out of this dilemma...buy fleet oil. NAPA sells their own brand of fleet ( truck) oils ... cheaper than the brand-name stuff; I use their 15W40 stuff.I don't worry about the tiny "0 W 0" MPG benefits...the price ain't too bad, either. Other generic brands are out there, I'm sure.
Also, the price of GM's EOS (engine assembly lube) has tripled lately! Any connection? EOS , formerly Engine Oil Supplement ( now changed just prior to the feds cracking down on the wild claims of the oil additive folks) , is laced with this zinc-based compound. Hmmm....
I'm sure Google knows about these moves ... check it out. Spread the word? -whitevette

[craig5_12]

Amsoil does state their oils are supreme and can run for longer time periods with the proper filtration...one way to compat expenses (for a DIY'er) is to drain a quart and then add a quart (or so) every 3-5k miles along with changing the filter. This would keep the oil quality pretty consistant whilst being cheaper than a full blown oil change.
Amsoil is expensive, but lots of other companies say they can go for longer intervals too. I've got Napa 10w30 in my Accord now...but I'm going to get Amsoil for the engine and tranny next time...

[Ford Man]

Originally Posted by rjacob

I have been told the engine in my car can last to 500,000 miles. So I try to take care of it.
Any comments, concerns, or recommendations on my oil change?

My daily car is a '88 Ford Escort and currently has 479,000+ miles and never been rebuilt. It currently uses a quart of oil about every 1000-1200 miles. I have always used conventional oil and changed the oil every 3,000-4000 miles most of the time, although there have been a few times when I would be busy and it would go 5,000-8,000 (probably no more than 10 times during its lifetime) miles between changes. I'll be using conventional oil for a long time yet since I have about 20-25 cases on hand that I purchased before the price of oil went through the roof and I bought it on sale.

[johnmyster]

My Honda was generally ready for more 10w-30 conventional at about 5000 miles - based on the "color of the oil on my finger" test. It too had a factory reccomendation of 7500.

[sickpuppy318]

I always notice an EXTREAM drop in FE when its oil change time. At 160,000 it uses practically none of the Mobile 1 Synth that i put in it. I can tell its time when the engine lacks power and FE. Now about 5-6k. Four and a half new quarts plus filter and the FE goes back to 36+. Right now getting about 31!!! I'm pretty sure any wear on the engine is happening now.

[whitevette]

Originally Posted by K

Any way you cut it, changing your SYNTHETIC oil at 3k is wasteful.

And if I were doing oil analysis, I would TOTALLY try 0W20. That would ensure that its not doing major damage.

Hmmm.... Getting oil analysed for 0W20 comes AFTER you use it, yes? And if it shows damage, how do you undo what your analysis shows? It seems to me the tail is wagging the dog....

[whitevette]

Originally Posted by sickpuppy318

I always notice an EXTREAM drop in FE when its oil change time. At 160,000 it uses practically none of the Mobile 1 Synth that i put in it. I can tell its time when the engine lacks power and FE. Now about 5-6k. Four and a half new quarts plus filter and the FE goes back to 36+. Right now getting about 31!!! I'm pretty sure any wear on the engine is happening now.

It seems you are changing every 5 or 6 K miles... and your Mobil 1 costs how much? Where is your gain? I'm not with you ... I use fleet oil (NAPA) for trucks 'cause it has zinc compounds in it (EP additive)... since EPA mandated all auto oils remove the zinc compounds...because that was damaging the converter element(s). Cheap, too....

[HondaHound]

Howdy,

I'm due for an oil change pretty soon and I called my mechanic and asked his advice about what kind of oil I should use. I have a 97 Honda Civic CX automatic. He said first off that synthetic oil is much more expensive (though it will last a lot longer) and that going to 0W20 is really only for hybrids because it's so thin. He said 5w20 is really the thinnest I should go. He guessed that the manual asks for 10w30.

I'm a little disappointed that my P&G is not gaining me much more MPG so I'm looking for additional ways to boost it.

HHINLA

[Ford Man]

I've used various brands of conventional 10W40 and various brands of oil filters in my '88 Escort with oil change intervals usually at 3-4K miles and filter every other oil change. My theory on oil changes is that a few extra quarts of oil is much cheaper that an engine overhaul. There have been a few times in its lifetime that it went 5-8K between changes when I'd be busy. Last time I changed the oil I had let if go about 7500 miles on each of the 2 previous oil changes and left the filter on for both oil changes, when I changed the filter I cut it open to see what was in it and it wasn't but probably 10-15% blocked. It has 481K+ miles on it now and has never had any type of oil related engine problems. For that matter it's never had any engine problems at all. It currently uses a quart of oil about every 1000-1200 miles. I'm not using high mileage oil in it. Maybe when it hits 1,000,000 miles I'll consider it. LOL