Foo - How often will I need to change my oil now?

On Saturday, I plan to change my car's oil for the first time (first time I will have changed oil that is). THe previous owner used a synthetic blend oil from Mobil 1. He said he changed it every 7500 miles. I think he just went by the bottle of the synthetic blend oil, it says "Guaranteed for 7500 miles". So I decided to spend the 6 bucks a quart and got fully synthetic. It's twice the cost, but my car doesn't take much oil, so I figured I might as well.

I am told fully synthetic motor oil will last even longer. What is a fair estimate for how long I can keep this oil in my engine? Assume normal driving conditions, not extreme dust or anything.

I guess I should also mention that I bought a new fuel filter too...

On Saturday, I plan to change my car's oil for the first time (first time I will have changed oil that is). THe previous owner used a synthetic blend oil from Mobil 1. He said he changed it every 7500 miles. I think he just went by the bottle of the synthetic blend oil, it says "Guaranteed for 7500 miles". So I decided to spend the 6 bucks a quart and got fully synthetic. It's twice the cost, but my car doesn't take much oil, so I figured I might as well.

I am told fully synthetic motor oil will last even longer. What is a fair estimate for how long I can keep this oil in my engine? Assume normal driving conditions, not extreme dust or anything.

Google is your friend phantomcow. :)

http://www.nordicgroup.us/oil.htm#Filter%20Change%20Interval scroll down until you see "Synthetic Oil" in large bold letters.

I've seen that. BUt that's one source, that doesn't agree with anybody else I've heard talking about this. I was hoping for some comments backed by experience.

I use Mobil-1 and the Porsche owner's manual recommends changing it every 7500, so I do...

On my Supra, I had used Mobil-1 and changed every 10,000 miles. That car lasted 254,000 miles when the suspension started needing too much work and I donated it to charity. :)

First thing: what does your owner's manual say? That's the "golden rule". Anyone who tells you every 3K miles is either trying to get you to spend money or living in the dark ages.

Now, if you go synthetic, you can, in theory, extend your intervals quite a bit. What you will need to do, however, is take a sample and send it to a lab for analysis. You'll change your filter at the same time and add some make up oil.

You can read some more about this here: http://www.blackstone-labs.com/

Heh, my car is up to 272k miles anyways. I just want to take all possible steps to have it last to the mighty 300k mark. If it can make it that far, I'll let it retire :). Maybe I'll try 10,000 miles. But should I change the filter before then?

Part of the equation also would involve how many miles, the condition of the engine. I don't know if I would go 10,000 miles, but you can usually get longer intervals out of a good synthetic. And acutally, "standard" oil these days doesn't absolutely have to be changed every 3,000. Many people go 5,000 between changes with no issues. Personally, I only use motorcraft in my Ford for both oil and filter, and change it at around 3,000 mile intervals.

Well, this car has had it's oil changed at 7500 miles and has lasted this long, so I don't believe the 3000 myth for a second. I believe that if the synthetic blend lasted 7500 miles, this should last longer still.

Every day. Oil = yum.

If you use synthetic, 7500 miles is a good time.

The best way to check it is smell fresh oil, then smell the oil on your dipstick. Then get fresh oil on forefinger and thumb and rub together, then do so with oil off of dipstick. If the oil smells burnt, or like gas you need to change it. Like gas is a big one in high mileage cars, the rings are going to let blowby get into the oil and gas kills oil. when rubbing them you shouldn't really feel your fingerprints all that much.

+1 for checking the manual, Auto companies spend millions on each car pushing it to its limits, the oil companies spend millions making you think you have to change it every 3k. Your manual won't be accurate for synthetic though, but I think synthetic usually gets double conventional.

One more thing, if you get lifter tick or rod knock change back to conventional oil next time. My teachers all said that synthetic is thinner so it makes tics worse (even though that seems to go agains the viscosity rating).

whatever you choose, try to be as regular as possible and don't go longer. regular oil changes are probably one of the most important things to preserve the life of your car

Heh, my car is up to 272k miles anyways. I just want to take all possible steps to have it last to the mighty 300k mark. If it can make it that far, I'll let it retire :). Maybe I'll try 10,000 miles. But should I change the filter before then?Shouldn't be a problem with mileage. I've seen plenty of Japanese cars well into the 300-400k mile range. As for filters, they are not all created equal: Engine Oil Filter Study (http://minimopar.knizefamily.net/oilfilterstudy.html). I use the Mobil-1 filters which appears to have superior construction and change it every 7,500-10,000 miles along with the oil.

I use Mobil 1 in the BMW and change the filter every 3250 and the oil and filter at 7500.

The best way to check it is smell fresh oil, then smell the oil on your dipstick. Then get fresh oil on forefinger and thumb and rub together, then do so with oil off of dipstick. If the oil smells burnt, or like gas you need to change it. Like gas is a big one in high mileage cars, the rings are going to let blowby get into the oil and gas kills oil. when rubbing them you shouldn't really feel your fingerprints all that much.


that's pretty good advice.
i'd do close to 3000 miles only if it were a carbureted motor.

i wouldn't go any longer than 7500 miles no matter what oil. and yeah changing the filter halfway through that interval is a good idea.

amsoil is good stuff.

Polara-What kind of car do you have. My Chevy had the filter near the low point. If you pulled it without draining the oil then....you just drained the oil the hard way.

Go to your auto parts store, Discount, Checkers, Auto Zone, whatever, talk to someone there. Pick someone about 40+ because it seems that the youngsters usually aren't as knowledgable about those things. I wouldn't go with more than a blend unless you have a hig performance car. You are throwing money away. I've heard you can't just switch back and forth either though because it's not good for the engine, breaks down the seals or something.

Go by what the owners manual recommends. The 3000 mile thing comes from people selling oil and oil change services.

Is your car losing any oil over time?

I use synthetic and go about 7000. My last truck, a Ford Ranger got over 300,000. I bought it new and used synthetic from the start. It still ran great when I sold it.

How often will I need to change my oil now?
As often as Dick Cheney tells you to.

I used to use and sell Amsoil and I'd change the filter out at 6 mos or 12.5k miles and top it off and then do a full oil and filter change at 12mos or 25k miles. I didn't drive 25k miles a year so I'd do it by the months instead. (I owned a modded Acura Integra with a JDM Type R engine)

I did a oil analysis after the first year and the oil came up fine. But you'll have to google your nearest Amsoil independent dealer as they are not sold in stores.

It saved me a ton of money and I asked a lot of my car at times. I used to use Mobil 1 full synth and change it every 3-5k miles since I drove my car hard. I did it at lower intervals for peace of mind more than anything else.

I have always done 6,000 miles with a filter change each time and conventional oil. By the way, synthetic oil leaks through the valve cover gaskets easier than conventional oil. If it already leaks a little bit, you might want to switch to regular oil.

It depends upon driving conditions and contamination. If your car floods with gas or gets antifreeze into the oil, the oil needs to be changed no matter how few miles are on it. And yes, fuel injected cars do flood in the cold weather. Just not as often as the old carburated models.

We had a synthetic oil slaesman come in once with a demstration on bearing wear. I was surprised at how well STP worked compared to the synthetic oil.

I enjoy changing my own oil, and I drive my car pretty hard, so $15 or $20 every 3,000 miles (3 months-ish) is not a big deal.

Polara-What kind of car do you have. My Chevy had the filter near the low point. If you pulled it without draining the oil then....you just drained the oil the hard way.

1990 BMW 535i, the oil filter is near the top of the motor in a permanent housing. All I have to do is remove one bolt, remove the old element and install the new one. I only lose about four ounces of oil doing this.

I use Mobil 1 in the BMW and change the filter every 3250 and the oil and filter at 7500.

That would make for one very weird schedule. Do you mean 3,750 and 7,500?

7500 is fine so long as you are not racing or pushing the engine hard....if you are, reduce the mileage between changes to reflect that. Reason is the heat will accelerate the breakdown of your oil.

I'm by no means an expert (or even very knowledgeable) about synthetics though...all my cars have been old enough that they came with natural oil, and I only used natural oil in them. I'm a big fan of using whatever the car was engineered around.

That would make for one very weird schedule. Do you mean 3,750 and 7,500?
Yes, I can't do math today.:)

I go by taste.