(Some makes and models of cars mentioned have been omitted to protect the guilty!)

I’m going to sound like a conspiracy theorist – it’s my grumpy rant about oil-change interval for our much beloved automobiles. I don’t know why, but I get terribly bugged by this every time I happen to buy a new car – which I did last month. I just feel liked being “bullied” into not making the right decisions about our environment and my pocket book.

For years, the recommended oil change interval for gas-powered cars in the US has been every 3,000 miles. This 3,000 miles interval is so well programmed into the psyche of the driving public that for many, drivers, mechanics, and dealers alike, it’s sacrosanct. I’m trying to break a superstitious habit.

Let’s start with the fundamentals – why we need to change the oil in the engine? Because oil gets “used up.” This means that after being in the engine crankcase, churned at high temperature by the crankshaft and circulated throughout the bearings, it will eventually lose it’s lubrication quality. This lost of lubrication is due to contamination from the engine (anti-freeze, unburned gasoline, metallic particulates from the bearing) and physical destruction of the oil molecules due to intense heat and sheer forces which the oil is subjected to.

But why 3,000 miles? This number has been considered the useful life of the oil and everyone who is alive today seem to know that number from “way back when I first learn to drive!” Some 30 years ago, it was brought to my attention that we in the US may have been taken for a ride. A visiting scholar from the UK decided to buy a car while he and his family were in the US so they could see the country. He bought the same car (make and model) as his own at home as he’s familiar with it. As the shade-tree mechanic at that institute, I was asked to help him check out his find. His first question after scanning through the US version of the owner’s manual was why the recommendation to change oil very 3,000 miles whereas the identical model he owned in the UK had a recommendation of 7,500 miles interval. Oh really? I did an informal survey among our overseas visitors from Germany, Japan, UK and France and indeed everyone said that their oil change intervals at home were anywhere from 5,000 miles to 10,000 miles. So, was their oil better than ours? Is their driving conditions less demanding? Are their gasoline (petrol) cleaner? The answers were no, no, and no. Car owners outside the US were just not brainwashed with the superstition that oil only lasts 3,000 miles.

15 years ago – I bought myself a brand new luxury car and the recommended oil change interval list in the users manual was every 7,500 miles! Wow.. finally? But no – after signing all the papers for the purchase, I was introduced to the service manager and the first thing he reminded me was to make sure I bring the car back every 3,000 miles for an oil change! No, no, no.. I protested – the manufacturer recommended 7,500. I also found out that the same car sold in it’s native country of Japan (but under a different make and model name) had a recommended oil change interval of 15,000 kilometers (almost 10,000 miles.) So, nice Mr Service manager started to explain to me why I should ignore the manufacturer’s recommendation and get the oil changed every 3,000 miles. It’s CHEAP INSURANCE to protect an expensive car. I was not convinced – and assured him that I will bring my car back to his dealership every 7,500 miles for an oil change – and since they have very good record keeping, I don’t expect them to hassle me about my warranty if anything goes wrong with the fine engine during the warranty period. (It also helped that their charge for oil change was only $10 more than the neighborhood quick-change outfit and they thrown in a free rental car for the day and they wash my luxury-mobile before I pick it up – so it worth taking it to them.) But after each oil change, they put a sticker on my window to bring the car back after 3,000 miles – which I duly ignore and brought the car in again at 7,500 mile interval plus or minus 200 miles. They never harassed me again for a couple of years until a new service manager came on board and he started all over again about bringing the car in very 3,000 miles.

In the last 50 years, technologies we encountered in every aspects of our lives have improved greatly – so why not the automobile industry? Shouldn’t oil have a longer useful life now than 50 years ago? Shouldn’t the oil filters be better at removing contaminants from the oil then 50 years ago? Shouldn’t metallurgy have improved the engine bearings? Shouldn’t engines have a much better combustion control systems to keep uncombusted contaminates off the crankcase? The answers are of course yes, yes, and yes! But we are being bullied and intimated by the purveyors of more frequent oil change proponents who have a lot to gain by our acquiescence to their scare tactics?

To satisfy my own curiosity and to shut Mr Service Manager up, I decided to actually send my oil to a lab to be tested. There are many laboratories that will test used oil and will give you a list of contaminants and a report of the general health and well being of the engine from which the oil came from. It only cost about $25 and a 4 oz sample of your oil. Many large fleet owners use these labs rather than depend on mileage or hours of operations to determine when oil should be changed. (Google “oil analysis” and you’ll find these companies.) When my luxury mobile had about 120,000 miles, I sent in a sample each at 3,000, 5,000 and 7,000 miles after the oil change. The results that came back was astonishing and very educational. It showed that all the 3 samples had pretty much identical metallic contamination – very very low – indicating very little wearing of the engine. They all indicated no anti-freeze – indicating that the head gaskets were good and the integrity of the engine block. The oil analysis report also indicated no gasoline contamination – indicating that the piston rings and combustion metering was perfect. Most importantly, the report indicated that all three samples showed very little change in viscosity over the period of use, indicating that the oil had not deteriorated. I shared the reports with the service manager, buttering him up with kudos for the fine engineering of the brand’s car engine. He was satisfied that I’m not ruining the car by changing oil every 7,500 miles – I claim that I could have gone another 7,500 miles with the state of the oil they just poured out.

But the saga continues. At 200,000 miles, with the car in almost mint condition and engine purring like a kitten, I traded it in for a Hybrid. (I missed my 14-speaker, power-everything luxury-mobile but changing from a 15 mpg to 50 mpg commute-mobile was good for my pocket book and green-conscience.) My new hybrid came with a factory recommendation of 10,000 miles between oil change. Hallelujah – amazing – a manufacturer finally stepped up to the plate and is willing to say that oil chemistry, engines control and fluid filtering technologies have improved and we don’t have to waste oil changing it so often when it’s obviously not needed. But guess what, after the first 10,000 miles with the hybrid, when I brought it in for its first oil change, I was accosted by the service manager who tried to convince and cajole (more like cohere and threaten) me into bringing it in for oil changes every 3,000 miles! No.. No.. NO.. I protested – unless he can show me a recall notice, service bulletin or service manual addendum from the manufacturer, I will stay with the recommendation printed in the users manual. So, I duly took the hybrid in to the dealer every 10,000 miles for the oil change and they duly slap a next-service reminder sticker after each service to come back in 3,000 miles, which I duly ignore!

Last month, I succumbed to the ultra-cuteness of the Smart Car “fortwo” model (even the model name is too cute!) and bought one. The overjoy salesman was more than eager to tell me all the great things about the little bugsy looking two-seater – the highlight of which was that it only needs service (ie oil change) every 10,000 miles. I starred at him with a look of incredulity! “Yea, that’s what you and the manual say, but what would your service manager tell me?” I hissed. So, we walked over to the service manager’s office and I asked him directly to which he replied “we do what the service manual says and if it says oil change every 10,000 miles, then every 10,000 miles it is.” Now, that’s different.. but we’ll see. I only have 950 miles on the little thing and when I bring it back at 10,000, I know if he really meant it.

So, if I were to make this 3,000 mile oil change nonsense into a conspiracy, who is perpetuating it and who benefits from perpetuating it? Every good conspiracy theory has to have a beneficiary (usually the US Government, Big-Pharma, etc) The three obvious suspects are 1) Oil Companies, 2) Car manufacturer and 3) Oil Change service industry including car dealerships.

Oil companies are one of the least beloved industries in this country so it’s tempting but as I see it, we cannot hang this one on them. Yes, they’ll sell more oil if we change more often but they can charge more for longer lasting oil. In fact many brands proudly tout that you can leave their oil in for 25,000 miles and more. It is in their interest to flaunt how good their oil is and give customers more confidence in using their brand. They make money charging 5 times more for oil that will last 3 time longer. It’s good profit for them. Car manufactures are recommending longer and longer intervals between oil changes. Intervals of 5,000, 7,500 mile intervals are very common and many are recommending 10,000 miles intervals. They understand that their engines are much better made than 50 years ago with higher quality material, more accurate fuel/air mixing resulting in cleaner burning engines. Since they have to underwrite the warranty for their engines, it is in their interest to recommend the longest possible interval they can statistically justify. So, if they recommend 10,000 miles you can be assured that it will be good, for the penalty is on them to fix a bad engine at a cost to them financially and more importantly, their reputation. Oil Change businesses are the only ones to lose if you change your oil less often. As car engines become more and more reliable; as computer technology took over more and more of the engine control, there is less and less things that are repairable in the engine. The modern automobile engines are now so complicated and computerized that most of the problem can only be diagnosed by specialized computers and software, specialized for a particular make and model of the engine. This means that dealers are doing most of the repairs but even then, with the reliability, their main income stream may well be the “routine” maintenance, oil change being one of them. They want to scare you into bringing your car back for more “routine” maintenance. The street corner gas station has long gotten out of the repair or maintenance business. The “quick-change-while-U-wait” is the fast-food equivalent for the auto-industry and is entirely dependent on routine maintenance. They really really want (need) you to visit them every 3,000 miles to stay in business. In addition to changing oil, they will also try to sell you additives for every liquid in your car. They will try to convince the naive and uninitiated to buy the additives and come back more often for oil changes by showing them how “discolored” the oils are compared to new clear right off the can samples. How else can “Quicklee Lube” charge only $19.95 for an oil change? Note: discoloration of your engine oil after even a mile of driving is not an indication of anything special!

Seriously, I don’t know if there really is a conspiracy perpetrated by the oil change businesses. It is really up to us consumers to rid ourselves of this superstition that oil formulated by laboratories with 21st Century know-how and used in engines with advance electronic management can only be good only for 3,000 miles. The manufacturers know better – go with their recommendation for they have everything to lose by recommending too long an interval. If there is a problem with what they recommend in the owners manual, they will have a service bulletin issued to the dealers and an amendment to your manual. Don’t waste oil – yes, I know they get recycled but why waste the resources to recycle more oil than is needed. And especially for your pocket book and inconvenience, why change oil 2 or 3 times more frequent than is really needed.

End rant ..