How far can you really go between oil changes (using conventional oil)

[waterjug]

I've always wondered, because when I was younger it was always 5000 miles, then it was 3000. I know they have the longer-lasting synthetics, but just with regular conventional oil, on a regular sedan, nothing sporty. It's got to be more than 3000 miles right?

 

[olds]

Depends on where/how you drive. Dirt roads and high RPMs = 3000
Asphalt and normal = 5000+.

 

[T2urtle]

Car/engine plays a huge role in this as well other then type of driving. Like city, 10 minute trips in stop and go VS 30 minute all highway drive.

 

[Soccerman06]

Whatever the manual says for extreme wear.

 

[dbk]

around 5000 to 5500.. usually when my car says oil life is at 15% or 10%

 

[kitatech]

Well, moderator fuzzybabybunny started a similar thread last week, and though FBB never responded, you'll see a lot of interesting responses here...
http://forums.anandtech.com/showthread.php?t=2316745

 

[colonelciller]

how long do you want your engine to last?

 

[HeXen]

I just change it after it reaches 3k, it's really not a big deal. I just use regular oil or whatever is cheapest, chances are the rest of the car will fall apart or i'll sell it long before the piston rings, bearings..etc wear out anyway.
Though I have a lawnmower that I've had for 8 years and never touched the oil, got it used at that. I've heard some stories of vehicles going years without oil changes

 

[kitatech]

...here's my take on conventional oil:

If you drive 10k miles or fewer per year, you're probably doing a lot of city driving, so the engine would benefit from a 2x year OCI...3x/year if a lot less than 10k...

If you drive as much as 15k miles a year then you're likely running a decent amount of highway miles, so changing oil 3x yearly would be a reasonable 5k mile OCI...20k miles/year would benefit from an OCI with the changing seasons.

You know your driving habits, but an OCI of 3.5k-5k miles will be just fine....

...now don't forget all the other fluids...coolant, brake, power steering and transmission fluids...change them every 3 years/40k miles, regardless of their "lifetime" formula characterization.

 

[JCH13]

My SO runs 7,000-7,500 miles on conventional oil and gets it changed as soon as her car reads 15% oil life. 2009 Civic, FWIW. The car is over 70K and runs quite nicely.

I change my MS3 every 5k miles with synthetic.

I change my Miata every 2-3k miles with synthetic, oil-cooled turbo cars love to cook oil.

 

[overst33r]

Every 7500 miles for me. 9000RPM 4 cylinder with 140k on the clock, runs like a champ.

 

[Fritzo]

Whatever the manual says for extreme wear.

This.

 

[Vic Vega]

How far can you really go between oil changes (using conventional oil)

Try it and be sure to let us know. :whiste:

 

[LTC8K6]

Until the rods knock?

 

[Tsavo]

Whatever the manual says. I'll stick to that way of doing things until I become an engine designer with unlimited access to petro engineers.

 

[phucheneh]

Soooo many of these threads. This is why I suggested a FAQ for ATG.

Whatever the manual says for extreme wear.

I am amused when I see this in manuals. Seems most common for transmission service. You'll see something like:

Transmission service is recommended every 60,000 miles, except in cases of extreme conditions, where the recommended interval is 30,000 miles.

And then they clarify that extreme conditions are: towing...any operation in <32* temperatures...any operation in >90* temperatures...stop and go traffic...[insert increasingly absurd description of everyday driving].

To me, it basically says 'hey, we're advertising an extended maintenance interval to make our car seem more economical...but we don't recommend it at all.'

 

[hans007]

when i had an 05 acura TSX the manual said 10k miles on regular driving cycle, and 5000 on extreme like, hot and lots of traffic.

i changed oil every 7500 miles and never had a problem. yes it was regular not synthetic.

 

[Leyawiin]

For the last 20 years I've been doing it around 5K with regular oil. Mostly city driving. Never had anything close to resembling an engine failure in any of them (including a crappy 89 Taurus).

 

[Jimzz]

I personally do 5000miles or once a year. I know some cars say you can go longer but that seems to be a safe bet with regular oil.


I also do 30k for my trans fluid as well.

 

[jaqie]

We have a 1991 ford probe LX with 175k+ miles, and a 3.0L NA V6. We like to power up to 55 once in a while in rural areas, and that is hard on such an old engine so we use penzoil high mileage 5w30 and look at the clarity of the oil for when it needs changed. We just had it changed (local place, really nice, let you watch, full service, shows you oil level and color before and after, et cetra) like yesterday... 2200 miles on the last change.

The car could use new gaskets and seals, but is running quite well for so many miles, just gotta keep the oil topped off, it ate a total of 3.5qt in that 2200 miles.

 

[Fritzo]

when i had an 05 acura TSX the manual said 10k miles on regular driving cycle, and 5000 on extreme like, hot and lots of traffic.

i changed oil every 7500 miles and never had a problem. yes it was regular not synthetic.

Modern standard oil is so refined now that it's about as good as synthetic oil was 10 years ago. You're seeing newer cars switching back to standard oil as a result.

 

[Throckmorton]

Modern standard oil is so refined now that it's about as good as synthetic oil was 10 years ago. You're seeing newer cars switching back to standard oil as a result.

I see statements like this a lot but is it really true? Doesn't the mineral oil still break down and get less viscous as it wears? True synthetic doesn't thin out, according to Bob Is The Oil Guy.

 

[JCH13]

Synthetic oil definitely changes viscosity with use, just not as dramatically as conventional oil can. It would be insane to think otherwise.

 

[Fritzo]

I see statements like this a lot but is it really true? Doesn't the mineral oil still break down and get less viscous as it wears? True synthetic doesn't thin out, according to Bob Is The Oil Guy.

Yeah, nearly all the contaminants are removed from better refinement procedures. The more pure the oil, the longer it lasts.

 

[railer]

Is this going to be a weekly topic now?

Follow your manual. My manual, AFAIK, does not make a distinction between dino and synthetic oil. It states to follow the OLM, which I will do because I don't have OCD, nor do I believe that I know more than the people who engineered the car.

In my case that's probably around 10k - 13k miles on dino oil.