Welcome to the Twilight Zone of those of us who predominantly use EV. I’ve only used 17 gal of gas in a little over 2 years, 16,000+ miles and 22.8 hours of engine running (by hour meter inductively coupled to a spark plug).
So we know from a standpoint of miles and time driven in HV plus time spent in the infrequent System Check engine starts that the oil is hardly used. I verified this with an oil analysis. The other two facts we know are that Honda states to change the oil and filter at no more than one year intervals even if the MM is not triggered and that GM allows up to a 2 year interval for the Volt PHEV.
Go beyond these hard facts and you enter the murky and somewhat uncharted waters of opinion and supposition. so here we go down the rabbit hole.
You have to consider possible warranty problems that however unlikely, will be potentially serious financially, and then you have to consider oil and engine lubrication issues.
So let’s start with possible warranty problems. If you choose not to follow the manufacturer’s maintenance schedule you will risk giving them a reason to deny your claim. The “murky waters” here is how big a risk that actually is and how adverse each individual is to risks in general. So here’s my opinion. On the one hand, the corporate bean counters would probably love to find a way out of a costly warranty repair, but on the other hand the marketing, public relations dept. and dealerships wouldn’t want to get dragged through the dirt on this. So I think the risk is real but just difficult to quantify. I personally would not want to give Honda any reason at all to question my future power train warranty claim because lawsuits are so expensive that it’s not cost effective to fight it. I prefer the much easier and quicker no question about it, iron clad, BAM!, it’s a slam dunk scenario.
As to oil and filter concerns. Here we really go ‘round the bend and down the rabbit hole. As I’ve said more than once on the forum, If you want to start WWIII, just bring up oil and filter brands and conventional “wisdom” on lubrications issues. For a more in depth study of tribology just go to
BoBistheoilguy.com if you have several lifetimes of spare time lying around. In a nutshell, I’ll just opine that oil can be contaminated by combustion blow-by products, condensation, and engine wear particles. Then add in depletion and degradation of additives and acidification. The end result is that I think it’s quite reasonable to assess oil life by overall time and not just miles or in our case engine operation time.
So where do all these facts and opinions leave us (or more precisely, me). Well, we have a risk that can be argued as to its probability but that has a potentially high financial consequence. That is a risk that I am unwilling to bear since mitigating it is the rather trivial cost of time and money for an annual oil change. It also helps that I keep cars for a very long time and so am more meticulous with proper maintenance than those who trade often and are less concerned with longevity issues.
As always, YMMV (as in your risk aversion and risk assessment may vary).
Full disclosure:
Even though I agree that the MM appears to use total miles and not just HV miles in its calculations and usually triggers before the oil life is used up, it’s really a non issue for me. This is because I drive >90% in EV and <8,000 miles per year, so my MM triggers at just one week shy of a full year. However if I drove enough total miles that my MM triggered at less than a year (and my HV miles were under 7,500), I might throw caution to the wind and still do just the once a year oil change. It’s not a money issue but more of an environmental issue for me and besides, I just can’t see throwing out oil before I “know” it’s useful life is over. Especially since no scientific study has shown any benefit to changing your oil at 3,500 miles instead of recommended intervals.
Sorry, this kind of got long winded.
