OT: synthetic oil life, time-wise

Actually the norm is 3 months or 3000.

-but- No you cant do 15,000 between changes, though many people can. Because, judging from your post, you dont drive long enough each startup to burn out condensation/fuel contamination

Keep doing it at 6,000

BTW, all synthetics are NOT the same.

"JohnV@nn" wrote in news:1145231655.674714.228730 @i39g2000cwa.googlegroups.com:

Just change it according to the owner's manual and you can't go wrong.

Joe Calypso Green '93 5.0 LX AOD hatch with a few goodies Black '03 Dakota 5.9 R/T CC

what do you recommend? I've been planning to use Mobil 1.

: > But now I have bought a baby hauler that requires synthetic oil, and : > I've been trying to find out the life of synthetic oil, in terms of : > time, not mileage. Everything I can find gives the life in mileage : > (everything from 6k to 15k depending on the source). : >

: > Should I keep on assuming 6 months is the life span of low-mileage : > synthetic oil, same as dino oil? Can anyone point me to any time-wise : > longevity info? : >

: > Thanks, : > John : : Just change it according to the owner's manual and you can't go wrong. : :

AND if it's new, and under warranty, if you don't abide by the mfr's recomendations, and you have a problem, you're screwed.

I change my Amsoil every 12 months, and a warranty can only be voided if the oil is proven to be the cause of failure at which point (in my case) the oils warranty will pick up.

I've got a pretty nice baby hauler myself -- a Honda Odyssey -- and it's doing fine on the dino stuff.

Paul

That's what I use. Never had valve-ticking in any of my beaters, either. Even though some started with it. Now have three secondary vehicles all with over 185K, no clacking even at startup.

I assume you have trips, at least once a week, where engine runs at least

30 minutes without cooling... if so 6 months okay.

If most trips like that, roll your own dice..

*****EXCEPT*****

If vehicle's under warranty, then you better pretty much follow the owner's manual. And use Mfr spec weight eg; 5w20 is Ford's

Read this:

Skim the testing methodology, look for the first results.

I'll have to read that, I have some interesting reading about ultra-filtrations effects on engine oil too. I'm sure it won't change any of your habits but if I can find an online source it is very interesting reading.

There is no magic mileage number to change your oil at. Frequency of oil changes should be based on the type of driving you're doing. Lots of stop and go, short trips, dusty locations, hard driving/racing are all hard on oil. Highway traveling, long trips (20+ minutes), living in a "green location", and leasurely driving can mean you can go well beyond the old standard of 3 months/3,000 miles. (Note: Water/antifreeze temperature is not an indicator of oil temperature. An fully warmed-up engine has hot oil.) That said, *I* believe a

*good* modern synthetic oil, under the right conditions, can last nearly 10,000 miles -- 7,500 being a good safe average.

Oh, and Mobil 1 is a good quality synthetic.

Patrick

Most factory recommendations(RTFM) are now in the 5K to 7.5K miles oil change interval.

I'm at 14K now in my Taurus(Mobil 1). The oil wasn't even dirty at 10K. Last oil change was at 18K. 20K is not unreasonable for Mobil 1, 25K if you do 100k per year. Could you imagine doing 33-34 oil changes a year?

Rob

very interesting, I see that they are using one year as the time limit. Also since I posted this question I have seen another reference that said (paraphrasing) you should change synth. oil "at least every 2 years even if mileage is still low."

The thing I found most interesting in the study you referred me to was that the protection provided by the synth. oil got better after the first couple thousand miles; the best protection was from the 4k to 18k mark; first 3k miles were not so hot. So it seems changing synth. oil every 3k is doing the engine more harm than good.