Recent Topics
Michelin jack won't lift a load
by 10WSmuckers. 09/23/18 01:32 AM
Synthetic for a 30 year old engine?
by geissjr. 09/23/18 01:02 AM
Phone Books
by csandste. 09/23/18 12:11 AM
Inside the Fuel Tank / EVAP system
by StevieC. 09/22/18 10:31 PM
Toyota Pink + RMI-25 10 years
by burla. 09/22/18 10:27 PM
Cartridge filter?
by Camprunner. 09/22/18 10:23 PM
Should have changed it?
by parshisa. 09/22/18 10:14 PM
Meijer QSUD Full Syn 10w30 $8.11 5qt jug
by Spartanfool. 09/22/18 08:40 PM
Whats in your beef burger
by CourierDriver. 09/22/18 08:28 PM
Headlight brightness fluctuates on 1987 Golf
by vavavroom. 09/22/18 07:56 PM
"New" Beater
by SilverGt. 09/22/18 07:22 PM
Eschewing computer controls
by buck91. 09/22/18 06:41 PM
Leak/drip left front 13 Ram 4x4?
by irv. 09/22/18 06:22 PM
5w20 oil choices
by 53' Stude. 09/22/18 06:05 PM
site security
by RF Overlord. 09/22/18 06:02 PM
Richmond Raceway
by Warstud. 09/22/18 06:01 PM
Redline D6 ATF substituting for Toyota WS
by Patrick0525. 09/22/18 05:29 PM
XG3614 Cut Open 13,400kms (8,375mi)
by mcwilly. 09/22/18 05:25 PM
Torn Purolators: they DO TEAR!
by 53' Stude. 09/22/18 05:07 PM
Newest Members
HondaTech250, SandCruzer, sbgti96, cosmoblau, Sarrge
66044 Registered Users
Who's Online Now
27 registered members (BlakeB, Billbert, ArrestMeRedZ, CleverUserName, Astro14, ctechbob, 1 invisible), 741 guests, and 42 spiders.
Key: Admin, Global Mod, Mod
Forum Statistics
Forums67
Topics290,867
Posts4,851,573
Members66,044
Most Online3,590
Jan 24th, 2017
Donate to BITOG
Previous Thread
Next Thread
Print Thread
Hop To
Page 1 of 3 1 2 3
How many months can a synthetic oil last #4660465
02/08/18 11:10 PM
02/08/18 11:10 PM
Joined: Jun 2016
Posts: 8
MI
BrianApp Offline OP
BrianApp  Offline OP
Joined: Jun 2016
Posts: 8
MI
How long, calendar wise, can a synthetic motor oil last in a car. I can go years in the 7,000 MI recommend interval but I thought I remembered that oil should be changed every six months regardless of the miles. That may have been talking about conventional oil though. I took it to the dealership but they said it wasn't due. With $20 oil changes for life they are motivated to keep the changes to a minimum. They don't care if the engine life is reduced but losing money on oil changes is not something they want to do.

Re: How many months can a synthetic oil last [Re: BrianApp] #4660481
02/08/18 11:30 PM
02/08/18 11:30 PM
Joined: Jun 2017
Posts: 553
DFW
JustN89 Offline
JustN89  Offline
Joined: Jun 2017
Posts: 553
DFW
Depends on too many factors to give a one-size-fits-all answer. While it's generally accepted that a quality synthetic can easily surpass the 12 month mark, the only way to know how long the oil will hold up in your particular engine is to get a UOA done.

Re: How many months can a synthetic oil last [Re: BrianApp] #4660491
02/08/18 11:46 PM
02/08/18 11:46 PM
Joined: Aug 2008
Posts: 3,162
USA
Reddy45 Online shocked
Reddy45  Online Shocked
Joined: Aug 2008
Posts: 3,162
USA
Not that it represents anything, but I swear someone posted a UOA here of an old truck that hadn't had its oil changed in 2 years and the TBN was still pretty good.

Re: How many months can a synthetic oil last [Re: Reddy45] #4660493
02/08/18 11:49 PM
02/08/18 11:49 PM
Joined: Mar 2015
Posts: 5,030
Virginia
bbhero Offline
bbhero  Offline
Joined: Mar 2015
Posts: 5,030
Virginia
Great day... But I think you are right about that... It was like 2 yrs plus and that oil was still good.


Nissan Altima 3.5 Coupe
Quaker State High Mileage 5w30 Purolator Boss 14610
"Treat your family like your friends and treat your friends like your family."
Re: How many months can a synthetic oil last [Re: BrianApp] #4660495
02/08/18 11:51 PM
02/08/18 11:51 PM
Joined: May 2013
Posts: 2,093
Saskatchewan, Canada
Johnny2Bad Offline
Johnny2Bad  Offline
Joined: May 2013
Posts: 2,093
Saskatchewan, Canada
I give up. How many?


'57 FL Straight 50 wt
'90 Miata 1.8L w/Rotrex Supercharger [Mobil1 0W-40]
'96 Ram 1500 [3.7L Mobil1 0W-20 / 1L 15W-50]
'01 PT Cruiser [Mobil1 0W-40]
Re: How many months can a synthetic oil last [Re: BrianApp] #4660496
02/08/18 11:51 PM
02/08/18 11:51 PM
Joined: Sep 2014
Posts: 2,097
US-WA
Dyusik Offline
Dyusik  Offline
Joined: Sep 2014
Posts: 2,097
US-WA
There was a report with dino hdeo that was looking fresh after many years. 7? Can't remember.


95 Cherokee 190K DELO 10W30, XG8
07 IS250 100K Napa 10w30, FULL
04 YZF-R1 19K DELO 15w40, XG7317
99 HD XL1200S 20K VR1 20w50, NG1515
14 RX450h 33k PP MIX, NG7047
Re: How many months can a synthetic oil last [Re: BrianApp] #4660510
02/09/18 12:15 AM
02/09/18 12:15 AM
Joined: Jul 2017
Posts: 542
Texas (south)
FermeLaPorte Offline
FermeLaPorte  Offline
Joined: Jul 2017
Posts: 542
Texas (south)
7,000 thousand is the most if you want to keep your vehicle for a long time.


Always Mobil 1
2014 1.6L Nissan Versa Sedan, 5 spd, 5k OCI.
2011 3.5L Chevrolet Impala, Automatic, 5k OCI.
Re: How many months can a synthetic oil last [Re: FermeLaPorte] #4660512
02/09/18 12:23 AM
02/09/18 12:23 AM
Joined: May 2004
Posts: 155
alberta
CONMCK Offline
CONMCK  Offline
Joined: May 2004
Posts: 155
alberta
Good question. My 2005 motorhome with the ford V-10 gets an oil change every 2 years. Mind you the oil usually only has approx 3000 miles in those 2 years. That's using mobil 1 5w-30 full synthetic oil.

Last edited by CONMCK; 02/09/18 12:24 AM.
Re: How many months can a synthetic oil last [Re: BrianApp] #4660513
02/09/18 12:24 AM
02/09/18 12:24 AM
Joined: Dec 2016
Posts: 6,239
Waco, TX
Linctex Online content
Linctex  Online Content
Joined: Dec 2016
Posts: 6,239
Waco, TX
There's a member on here that's got 5 years on Mobil 1.
UOA sample says it's still good.

My 1943 Farmall H has had the same 15W-40 oil in it for around 20 years now. The thing runs perfectly. The Ford industrial engine in my wood chipper has oil that's even older than that, But it only gets used an hour every couple years. (This is all plain "dino" oil, BTW)

It's been proven on here many times - calendar date on oil really doesn't matter.


"The evidence demands a verdict".
(Re:VOA)"it's nearly impossible to actually know the particular additives that are in there at what concentrations."
Re: How many months can a synthetic oil last [Re: BrianApp] #4660524
02/09/18 01:25 AM
02/09/18 01:25 AM
Joined: Feb 2013
Posts: 10,704
Phoenix, AZ
Nick1994 Online content
Nick1994  Online Content
Joined: Feb 2013
Posts: 10,704
Phoenix, AZ
A lot of months


2015 Hyundai Sonata 2.4L 84k Mobil 1 AFE 0w30 & OEM
2000 Toyota Camry 2.2L 230k Valvoline 5w30 & Fram Ultra
1996 Jeep Cherokee 4.0L 147k Mobil 1 HM 10w40 & Fram Ultra
Re: How many months can a synthetic oil last [Re: BrianApp] #4660527
02/09/18 01:37 AM
02/09/18 01:37 AM
Joined: Oct 2012
Posts: 4,621
Taiwan
Ducked Offline
Ducked  Offline
Joined: Oct 2012
Posts: 4,621
Taiwan
You say regardless of miles. That has to include 0 miles, so it then becomes almost equivalent to the oil shelf life question, except that an engine isn't normally a nominally sealed container.

Valid answers to the shelf-life question are mostly expressed in terms of geological time, or infinity.

Approximately.

Re: How many months can a synthetic oil last [Re: BrianApp] #4660531
02/09/18 01:49 AM
02/09/18 01:49 AM
Joined: Feb 2009
Posts: 17,141
Michigan
daves87rs Offline
daves87rs  Offline
Joined: Feb 2009
Posts: 17,141
Michigan
Well, my Cavalier is sitting at almost 2 years on it's QSUD change.....engine is still doing just fine....


Coming together is a beginning; keeping together is progress; working together is success.

Henry Ford
Re: How many months can a synthetic oil last [Re: BrianApp] #4660562
02/09/18 05:39 AM
02/09/18 05:39 AM
Joined: Aug 2017
Posts: 209
Cincinnati, USA
Dave9 Offline
Dave9  Offline
Joined: Aug 2017
Posts: 209
Cincinnati, USA
It depends upon the conditions under which you put on the miles you do. Suppose every time you drive it, you only go a couple miles. That is not long enough to warm up the engine, have it run lean, and have the oil heat up to cook off moisture. This is even more true in a Michigan winter where you might have to drive quite a while to get the oil up to temperature.

50 trips in this state is much harder on oil than 1, 50 mile trip. It also means starting the engine an additional 49 times, supposedly when engine wear most often occurs and where do these wear particles end up? Either as deformation or more often in the oil.

No it does not need changed every 6 months in "most" cases, but if you were to drive a mile a day every day, "maybe" it needs changed on a yearly schedule.

More to the point, if I were you with low miles, what I would do is "sneak" in an additional oil change between each of the dealer free 7K oil changes. Maybe use the same filter brand so they don't catch on (or don't, that shouldn't really change anything). Don't reset the oil change indicator if the vehicle is so equipped.

It may not be the perfect interval but it seems to make the most sense and still take advantage of the free oil changes.

Last edited by Dave9; 02/09/18 05:44 AM.
Re: How many months can a synthetic oil last [Re: BrianApp] #4660565
02/09/18 05:49 AM
02/09/18 05:49 AM
Joined: Mar 2008
Posts: 5,943
Michigan
ZZman Offline
ZZman  Offline
Joined: Mar 2008
Posts: 5,943
Michigan
The standard is 12 months from what I have seen.


2003 Mercury Grand Marquis. Rotella T6 Multi-Vehicle oil
2008 Sebring Hardtop convertible. Rotella T6 Multi-Vehicle oil
2006 Kawasaki Vulcan 900 LT. Amsoil Metric 10w-40
Re: How many months can a synthetic oil last [Re: BrianApp] #4660570
02/09/18 06:00 AM
02/09/18 06:00 AM
Joined: Oct 2005
Posts: 1,662
South Dakota
otis24 Offline
otis24  Offline
Joined: Oct 2005
Posts: 1,662
South Dakota
Depends on driving habits. I go strictly by Oil Life Monitor. The last two times, I have gone 10k miles (about 6 months) each time. But that included a 3k mile round trip in each case. I think there is a big tendency to focus on TBN while ignoring TAN. In general, my vehicle is a short tripper, but the OLM factors that in. I do not have any big trips planned before the summer so it will be interesting to see if the OLM trips sooner this go around.


1991 Chevrolet K1500 (4.3, 4x4, 86k miles)

2016 Dodge Grand Caravan
(3.6 V6) 46500 miles
Page 1 of 3 1 2 3

BOB IS THE OIL GUY® Powered by UBB.threads™