Oil Change Frequency

I do not go by hours.  When I check the oil, I take a look at the color of the oil on the dip stick, then I think about when the last time I changed the oil was.  I never let it go too far though.

There's quite a few things that will make an oil change necessary.  Two things for the "sitters" low hour uses will be condensation and the accelerated affects of water contamination such as increase in TAN (total acid number) and oxidation. The oil itself will be fine sitting for extended periods.  It's the contamination suspended in the oil that needs to be removed. 

Also, starting them without letting them get to full operating temperature for an extended period of time is extremely bad for the oil.  It's better not to start them at all if you can get them up to full temp for a while.

The Lubricheck is a hokey attempt at oil condition monitoring.  It cannot tell you everything you need to know.  It will give people a false sense of security or cause alarm when there's nothing wrong.  You should really use a commercial oil analysis laboratory and have your oil checked.  Once you have performed a baseline to get an idea, you can make oil change decisions from there. 

I have offered to help forum members before.  I am a long time AC forum member and been driving AC's for more than 40 years.  This is not a plug for my company since my target customers are large commercial and industrial customers. I own Apex Oil Lab in Grand Rapids, MI.  I will run full analysis on forum members oil for $10.00.  That will cover my cost for consumables and labor.  We can run all lubricating oil such as engine, transmission/hyd, gear etc.  Google apex oil lab to get the office contact information.  Ask for Jason so I can get you the pricing I posted.  Our single kits are normally priced at $34.95.

Jason

On a diesel???

DougS wrote: The problem I’ve always had with oil tests is they cost as much or more than the oil change itself. If you have something that takes 10 quarts of oil, I could see where a test might be worth it.

Doug,

In most cases the cost of analysis may be more than the cost of the oil.  Depends on what your end goal is for the analysis or oil change.

Ideally you always want to get back a perfect report with everything's fine.  It's the one time that you get one back with coolant contamination that you were unaware of but haven't damaged the engine yet.  Or your seeing excessive wear that you now have a heads up that there may be a serious issue before a catastrophic unexpected failure.  This is not as critical to a collector, but for someone that needs the equipment to perform in the field under extreme condition and time constraints a heads up is worth potentially thousands of dollars.  Most collectors or hobby farmers will do it out of interest but not necessity. 

Jason

Acidity in oil comes mainly from byproducts of combustion, if we follow the first assumption that there are not outside contaminates being introduced into the oil (i.e. it is stored in a dry place so excess moisture isn't introduced into the crankcase and it is being run long enough to warm up completely and evaporate any moisture in the engine), then the oil will buffer a certain amount of acidity with its additive package.  Thus, you change the oil, park the tractor for 6 months before using it, it shouldn't be much different than if you changed the oil right before you started it for the first time.  Likewise, if you run a tractor and it produces "x" amount of acid that is absorbed and buffered by the oil, that chemical reaction is going to happen rather quickly in the grand scheme of things, so if you look at the oil a week after running vs a year, not a whole log has changed.  Suspended solids may fall out of suspension, but if that happens, it should either be caught by filter when started again or pulled back into suspension.  

There are a lot of variables into a proper suggestion for you, but it really comes down to what you are comfortable with and how you use your equipment.  I had a tribology (study of lubrication) professor in engineering school that used to say, sometimes you had to lubricate the parts, but other times you had to lubricate the customers (it sounds a little wrong, but what  he meant was sometimes you have to do something just to make the customers feel comfortable).  The example he gave had to do with one of the early synthetic formulations at Mobil that was blue in its natural form.  No one would buy it because they were scared by the oil color, but as soon as they dyed it brown, they couldn't keep it on the shelf.  So whatever you do, make sure you are comfortable with the decision.

Hurst