Call me silly, but I am NOT waiting on 5,000 miles

Joe:

Dirt, grit, and metal true to a certain extent. Most wear metals under 25-40 microns will sail right through a conventional oil filter. If you install a bypass oil filter, than you will capture wear metals down to 5 micron and theoretically the motor will last forever.

Sludge and varnish are the result of oil breakdown due to operating conditions. Sludge is primarily a low temperature problem when the moisture from cold operation reacts with the oil, causes parafins and additives to separate, and makes a gooey mess. Varnish is high temperature breakdown, like a coking process.

Neither sludge or varnish will be caught by an oil filter, as most of these end up as deposits on the underside of the piston crown, in the piston ring land area, and the cylinder head. If there is excessive watery sludge though, it will clog the oil filter and put it into bypass.

How quickly an oil breaks down from normal operation depands on many factors. Everything else being equal, a good synthetic will last far longer than a conventional oil. A good European oil (ACEA A1, A3, A5, B4-02, etc) will last far longer than a regular North American API/SAE "Starburst" 5W-30.

A final point on motor oils: they are not perfectly clean when they leave the refinery. Depending on the age of the refinery, the type of screening process, the design of the column stages (Trays with perforations, plates, flappers, etc), and the last time a de-coking and flush was performed, you could get a batch of motor oil with very high insolubles.

As I stated earlier, Toyota has rolled back their recommended change interval from 7,500 miles to 5,000 miles. I think a lot of that was due to owners of 3.0 V6 motors trying to run the full distance with a cheap North American oil, and having sludged up oils. I used high quality Heavy Duty oils or synthetic oils, and had no issues.

At least the Asians still appear to put drain plugs on items like differentials. My 2000 GMC Sierra surprised me in having a drain plug on the front and rear differentials. A co-worker bought a 2004 and - surprise! - no more rear drain plug.

I guess some owners were actually changing the fluids and making the truck last a bit longer. Shame on them!

jay

 

That fully synthetic oil recommended by Toyota UK wouldn't happen to be the BP's Visco 7000 0W-40? It's supposed to be an excellent motor oil, not available here.

The environmental impact of used oil was largely ignored in North America until very very recently. I'm sure you will be dumbfounded and probably won't believe me, but this is the truth:

Up until 8-10 years ago, used motor oil was sprayed on gravel roads to control dust.

See, I knew you wouldn't believe me.

Even though a token effort is now made to "recycle" used motor oil, a lot of it is still dumped on the ground if folks think they can get away with it. And little mention is made of the used oil filters: the media is saturated so anywhere from 300-1500ml of used oil remains when the filter is tossed into the trash.

All those old oil filters leaching oil in a landfill ... yummy.

 

I thoght the oil change interval for all EU Prius was 16,000km or 10,000mi? They run either a semi-synthetic or a full synthetic.

How about the VW's sold in the EU that have oil change intervals of 2 years or 50,000km? No reports of engines blowing up left and right.

http://www.vw.co.uk/services/servicing/lon..._service_regime

http://www.vw.co.uk/assets/Longlife_servicing.pdf

 

Doc:

That brings up a VERY good point.

See, I thought there was a problem with Na, at least the testing lab assumed a slight problem. Toromont Caterpillar SOS Lab in Toronto primarily tests HD diesel motors, and such Na levels typically mean coolant seepage past the o-rings in the cylinder liners. Hence the note of caution on their part.

A lot of emails and a few phone calls later, the testing folks and engineers - who admitted this was their first all-aluminum motor tested and a Prius at that - reached the conclusion the oil itself and the metallurgy of the motor are responsible for the Na levels. In other words, a "normal" Na reading for this motor running Mobil 1 SuperSyn.

As you noted, the "usual" wear metals were insignificant.

But say you DID have a problem, such as a seeping gasket allowing coolant into the motor. In that case, you could change the oil every 1,000 miles and you'd still very quickly fu-beyond-ar the motor.

Or say you had a ruptured air filter, as Popoff suggested, or a hole in the intake duct. You could change the oil every 500 miles and you'd still quickly ruin the motor. Without some hard data, you’re just guessing. That can be expensive, dangerous, or just plain wrong.

jay

 

Hey Jay, have you seen the small compilation of Prius engine oil analyses I posted before? Just searched and could not find a copy on PriusChat. I could repost them, but for now, none indicated notable amounts of sodium in used engine oil.

I believe the part about engine oil/dust control. Oil containing PCB was formerly used in this way also. Yuck smiley.

 

yeah, if you've got cars with 200k plus miles it's probably better to change oil every 3k... but a new car can easily handle every 5k especially considering the fact that the prius engine isn't running nearly half the time.

 

[Sarcasm Mode ON] What the hell, it's only PCB. [Sarcasm Mode OFF]

 

Or, to put it another way, it's just plain silly to assert, contrary to all evidence, that an engine built at the beginning of the 21st century requires the same maintenance as one built in the middle of the 20th century. Technology moves ahead.

 

Evan said it about as thoroughly as can be, SignBoy. The only thing that I would add that Daniel alluded to is that the Prius is a totally different car than what most people are used to. It's designed to be as environmentally friendly and conservative on gasoline consumption as possible. Changing your oil less is better for the environment and Consumer Reports has mentioned before that even a conventional, gas-only vehicle doesn't need its oil changed every 3000 miles. The oil change industry just tells you to do it every 3000 miles to sell more oil changes, more oil and more oil filters. You're worrying over nothing.

 

OMG!!!!! How about saving it for me and I'll use the other 2500 miles left in it. This is wasteful!!!!!!

 

Slightly off topic, but the trend in industry is to carefully analyze, filter, and replenish the oil instead of disposing of it. In some applications, especially large 3-phase HV transformers, the disposal and environmental levies to used oil disposal are now prohibitive.

With more emphasis on proper filtration (Primary media and bypass filtration down to 5 micron) and proper fluid selection, we're going towards a "lifetime" fluid. In many industrial cases, the cost of routine fluid analysis is more than paid off in fluid change savings.

http://www.chem-ecol.com/mobile.html

http://www.mann-hummel.com/liquidfilters/?iKeys=17.1.219.0.0

 

I agree, but think in this case it's good for others to read.

 

It was a Shell Helix 10-40W I think - it was different to the one recommended in the manual but the dealer said, after giving it 1ms consideration, `oh, it will be alright`. When I said that he`d overfilled past the max mark on the dipstick by about 6/8" and my mpg had gone down he said `oh, it will be alright`. So I`ve changed my dealer (the new one took the 1/2 litre of oil out for free, and previously re-attached my number plate when it came off from slamming the back door too hard).

But why is UK 10k, and US 5k ? We are talking about the same engine aren`t we ?

We have special disposal facilities for waste oil here at our local dumps (if I did the change myself, which I`ve never done). The dealers charge us an `Environmental Charge` for disposal. I bet some people pour it down the drains though, which gives us all the chance then to taste the oil via our water supply in the long run.

 

Yes, same motor, but vastly different motor oils. There is a large difference in motor oil specs comparing EU to North America, and that has to do with the industry philosophy in general.

In the EU countries, the engine maker is free to specify exact motor oil specifications, viscosity, etc. The testing standards programme is run by the ACEA (Association des Constructeurs Européens d'Automobilies) in Bruxelles. You can look at the specifications at:

http://www.acea.be

In North America, the oil industry determines the oil specifications, through the API (American Petroleum Institute) and the SAE (Society of Automobile Engineers). Naturally it's in their best interest to promote frequent oil changes, it's good for business.

This is the same contradictory position held by the FAA (Federal Aviation Administration). On the one hand, they're supposed to be a "watchdog" and protect the flying public, on the other hand, they're supposed to promote the industry.

Guess who has the bigger bank account, the consumer or the industry?

You can find more information on the API but I have to warn you the information is closely held:

http://www.api.org

For example, their motor oil programme documentation costs $109 USD, so naturally the average person curious about what things like "SL" and "Starburst" mean will not proceed any further:

http://apistandardsonline.api.org/servlet/...234000&Env=BASE

Overall, the ACEA motor oil test sequences are run for a longer duration (200 hours vs 40-60 hours) than API test sequences, and are far stricter with regard to cold sludge and even make-up oil.

As an example, just 10 years ago a minimum spec 5W-30 could thicken 500% in use, and during the test the technician was allowed to add 7.5 litres of makeup oil. In most of the ACEA test sequences, maximum thickening is limited to 80-90%, evaporative loss under 15%, and NO makeup oil is allowed.

Currently the North American oils are still allowed to thicken 250%, evaporate 25%, and the technician is still allowed to add 7.5 litres of makeup oil.

If you followed my post about the used oil analysis at my 8,012km oil change, the Prius motor is VERY easy on oil. Provided you use a high quality synthetic. It's possible I could extend the change interval 2-3 times with no ill effects, but I would prove that with careful oil sampling.

Actually you're better off basting a turkey with used oil. The heavy metals, acids, and aromatics will lock in the flavor and keep the meat tender and juicy.

With promoted oil change intervals here of every 2,500-3,000 miles, there is no way all of it can be accounted for. And the issue of used oil filters is most troubling, most used filters are tossed out with the household rubbish to end up leaching into a landfill.

Modern motors, in a fully automated assembly and test run process, and modern motor oils, are capable of much longer oil change intervals, and these are still "safe" intervals.

As I mentioned previously, if there should happen to be a mechanical issue, say a leaking gasket allowing glycol into the crank, it wouldn't matter how often you changed the oil. You would still destroy the motor.

 

Just on observation:

It seems everyone has scared this thread's originator away. No further posts from him.

 

I hope not. That certainly wasn't my intention, just to pass along some knowledge.

 

Thanks for all the info. Definately fully synthetic (Helix Ultra) - I chose this because of what I`ve read in these pages.

I can easily believe the conspiracy theory on the US and EU oil. It`s a scandal.

 

Changing the oil every 100 miles works. Doesn't make it the proper thing to do.

OK, so in this corner, we have...

• Toyota engineers
• Jayman's oil analysis

While in the other corner, we have...

• It's what Signboy has always done and works for him

I have thought about it. I'll take evidence over 'cause I said so'. I'm sticking with 5,000 mi.

I don't think I'm the gullible one.

 

I can't help but think about an old story about a guy walking down the street snapping his fingers.

His friend asked him "why are you snapping your fingers?"

The reply "to keep the elephants away."

Friend "but there isn't an elephant within hundreds of miles."

Response "See. It works!"