What's new
CK5
Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members.

Oil change intervals? (synthetic or on conventional)

dyeager535

dyeager535

1 ton status
 Premium
Joined
Dec 13, 2000
Posts
31,571
Solutions
1
Reaction score
2,910
Location
Roy, Washington
I did some searching on the 'net, nothing. Did a quick search here, nothing.

Wondering if anyone has any "official" documentation from any oil maker about what kind of oil change interval is required in a mild, non-dusty environment, on a vehicle that is garaged for a year, then driven under "normal" conditions for about two weeks (engine gets up to operating temp and stays there during this usage, no around town jaunts) then put away again. Of course, it's started say monthly while stored, and allowed to get up to operating temp to keep the battery charged, etc.

In this case it has nothing to do with mileage, but more about the breakdown of the additive package, which happens over time. (And what happens when it sits on the shelf in a bottle???) I understand the issue with water and acid forming, but also should not be an issue since the vehicle is maintained/driven in a method that should burn off the bad stuff, then put away.

I couldn't find ANYTHING stating what kind of life you can get out of an oil that is in a vehicle that is almost never driven. Experience from automotive museums would probably be relevant.

I'm looking for hard data, not hearsay. All the manufacturers say follow the engine makers specs, but then of course go on to say things like "15k or 1 year" for synthetic as an example, but don't specifically address extremely low usage/time change intervals.

This of course is for my truck. I was thinking synthetic might save money in the long run due to longer oil change intervals, but at 6 months for conventional vs 1 year for synthetic, I'm still $$ ahead, and it doesn't take that much time to do anyways. I expected synthetics to have a much longer time interval, but anymore, I have no way of knowing if they are saying 1 year solely to ensure the idiots out there that really don't understand driving conditions get their oil changed before doing damage.
 
Last edited:
Hard data may be difficult to come by - likely time interval data only for a vehicle that is seldom driven. It might be useful to consider adding a bypass oil filter and going with an extended interval change - less worry about wear particles, dilution, etc.
 
I've seen and heard a lot of manufacturer recomendations. All I can say is have the oil tested at 3, 6, 9 and 12 months. As long as the tests say the oil is clean still you should be able to keep it in the motor.
 
Do we have anyone local that tests? I'd have no problem running a $20 test once or twice to discover this, but even at $20 I can change my oil twice still. :)

I filled out a "technical question" request to Castrol, they say they'll get back within 24-48 hours. I'm not expecting much.

Probably need to call Jay Leno and see what he does!
 
I'm thinking you just do your own tests for that first year. That will give you the facts of your vehicle. After that you should know how long your oil lasted and not have the need for further tests.

As far as who does the testing, look for a big rig mechanic...
 
As I expected:

"Thank you for contacting Castrol North America.
Changing the oil regularly regardless of the miles will eliminate any buildup of water in your crankcase and in the pan. This will eliminate the formation of rust from the inside out because of condensation which can form on the bottom of the pan under the oil.
Motor oil serves many purposes. Its primary function is to lubricate and protect, but it also keeps your engine cool and running clean. By changing your oil frequently, you remove by-products of combustion such as acid, soot, abrasives, water and unburned fuel. All of these substances can have damaging effects on both the performance and life of your engine.

You should check your owners' manual for their recommended oil change service. However, we recommend for ultimate protection that you change your motor oil every 3,000 miles / 5,000 kms (or 3 months, whichever comes first).

Thank you again for your interest in Castrol, The Technology Leader!

Castrol Consumer Relations"


Blah blah blah. As a matter of fact, I just read something about the oil change industry trying to keep people believing 3000/3 months. Big surprise here, they didn't answer my question, and indeed try to get me to change my oil more often than necessary for "ultimate protection". So I guess 3001/3 months and a day my engine is only protected. Obviously they don't pay their engineers to answer email.

I saw the 40,000 mile LS1 synthetic test, but that was driven fairly regularly as I recall.
 
Dorian -

your best answer would be to have the oil analyzed..you can contact titan labs ( titanlabs.com ) and order some oil analysis kits. stavely fluid services is the lab we use, but I've also used titan.

The test parameters of interest would be " water by karl fisher" ( to detect moisture), TBN number ( which tells how well the oil is resisting acids), and viscosity.

the key is to perform several tests, and look for trends. ( I know you know that, I'm just saying )

If it were my truck, I would just keep a trickle charger on the battery, and not bother with the monthly start up.. it's not running long enough to really burn off any contaminants or moisture, ( just warming it up doesn't really help).

as to mineral VS synthetic, it really doesn't matter.. they're both petroleum, and are both susceptible to contamination from moisture and blowby, and additive breakdown from heat.

only diff between the makeup of synthetic and conventional is that real synthetics 'SHOULD' be made 100% from PAO basestock, and have molecules that are of uniform size.. these are what give a real synthetic the ability to handle cold weather, and absorb more heat.

I say all of this to say that nowadays, any processed mineral oil, or PAO / ester, or PAO / mineral / solvent blend can be called a synthetic, and the qualities of a true synthetic aren't applicable to your storage situation..

what you want to be concerned about are the level and quality of the emulsifiers / demulsifiers in the oil..these are what keeps the moisture from attacking the oil. you HOPE the super duper synthetics have enough for what you are doing, but since anything can be called synthetic, it's a crapshoot if you are relying on the label, and advertised drain intervals.

analysis is the only way to know for sure.

as far as the oil breaking down, heat, combustion temps, and blowby are what kills your oils additive package the fastest, so since you don't drive it much, I wouldn't worry about breakdown.

I'd start with you favorite oil, and monitor that.. if you see things degrading faster than you like, then change..
 
Awesome, appreciate the reply!

Correct URL for Titan though...holistic stuff threw me on your link. :)

http://www.titanlab.com/index.html

Without calling them, any idea what the analysis costs?

And of course, sticking to one oil would be the only way to know that the results are repeatable, also assuming that they don't change the formulation as Mobil1 apparently did a few years back...
 
dyeager535 said:
Awesome, appreciate the reply!

Correct URL for Titan though...holistic stuff threw me on your link. :)

http://www.titanlab.com/index.html

Without calling them, any idea what the analysis costs?

And of course, sticking to one oil would be the only way to know that the results are repeatable, also assuming that they don't change the formulation as Mobil1 apparently did a few years back...
Click to expand...

Whoops, that's what I get for trusting the 'ol memory.. anyway, the tests should cost in the 20 dollar range.. you'll get a bottle to hold the sample itself, and a larger plastic container that you put the bottled sample into..

supposedly you can just mail the container itself, but I like to box it up with bubble wrap, just in case.

it'll come with full instructions too.

as to the other post about blackstone labs, they are another quality outfit you can deal with.
 
I figured for the price, it would take years to recoup even the one test cost, but it may be worth it. Unless someone has a link to any similar experiences online. :)

But $20 isn't as much as I expected, so when money becomes available again, I'll be able to do this...get a house I can finally garage a bunch of my vehicles to work on, and now can't afford anything for them. :)
 
The Army does oil analysis I believe for every item that has transmissions, engines, etc., except when in long term storage (can't recall what that term is) like on pre-positioned ships. So I believe you are right, there is probably some instruction on that, like intervals and what not, but I wonder if any of the data is actually out there on the testing done to get where they are, what oil is used, etc.
 
Just sent an e-mail to a freind in army who does heavy equiptment maintenece. Not sure where he is right now so questionable on his reply...
 
The term for the long-term storage stuff is "pre-positioned stocks". If he can get info on that it would be of benefit. Oil analysis is routine on everything else, part of the maintenance of the item. I suspect the oil analysis intervals for routine maintenance are no more than one year, probably six months or less.
 
Well my freind SGT. John xxxxx Army, who does vehicle repair and maintence says one year! That is the Army policy. Vehicle could sit ten years but needs a fluid change before running again. He did not have any technical reason and where he is stationed now does not expect to be able to find out why.

Maybe the oil companies have advised them the same as you?

I still don't buy it. Oil only lasts a year when sitting still? So any oil on a shelf at a store is also no good after a year?
 
eagle mark said:
I still don't buy it. Oil only lasts a year when sitting still? So any oil on a shelf at a store is also no good after a year?
Click to expand...

Oil in an airtight bottle on a shelf hasn't been exposed to anything that would contaminate it or break it down, so it'd be good for more than a year.

sitting in an oil pan is a different story. changing it every year is just easier - beats wasting time keeping track of every little detail.
 
4by4bygod said:
oil In An Airtight Bottle On A Shelf Hasn't Been Exposed To Anything That Would Contaminate It Or Break It Down, So It'd Be Good For More Than A Year.

Sitting In An Oil Pan Is A Different Story. Changing It Every Year Is Just Easier - Beats Wasting Time Keeping Track Of Every Little Detail.
Click to expand...

X 2
 
Thanks for the info here. I change the oil on my DD once a year (about 5000 miles). I use synthetic something or other.

I NEED to change the oil in my k5. Almost three years and haven't even had to add oil. I may have driven the thing 1000 miles at most.
 
You must log in or register to reply here.

Latest Posts

Top Bottom