Synthetic Oil & Filter evry 10,000 Miles?

I also am using synthetic oil but am observing 7,500 mile intervals. 10K miles might be too long if you are not having your used oil analyzed.

I question the amount that you are paying for the oil and filter. I think you should be paying no more than $5/qt for the Mobil oil, and you should be able to buy a Toyota-brand filter from your dealer's parts dept for $5 or so (some dealers selling via web price the filter at ~$3 each when you buy a case of 10). Hence the cost should be more like $23 each time you change the synthetic oil (using 3.5 qt.) and Toyota filter.

Also note that if you deviate from the 5K mile or 6-month oil change intervals, then you basically are waiving receiving any benefit under the powertrain warranty with respect to lubrication-related engine problems that you might have during the first 60K miles.

 

I use Amsoil and run 25,000 Miles between changes. All of my tests have come back normal so far. I had been running 0W-30 but switched to the 5W-30 at the last change. I didn't have issues with the 0W-30 but since the 5W-30 is recommended, I figured "why not".

No real reason behind using the 0W-30 other than that Amsoil did not sell a 5W-30 when I bought the car.

Edit: I also use the Amsoil EA filters which are rated to have a 25,000 mile lifespan.

 

I change the oil and filter every 6 months. Works out to be about every 7500 miles. Going by other owner recommendations, I use filters from either AC Delco, Wix, Purolator, Napa (silver or gold) or Toyota; and synthetic oil that meets ACEA A5/B5 and(BOTH) ILSAC GF4. I know Pennzoil full Syntec and Castrol full synthetic meet these specs, while Mobil1 used to but then reformulated to a lower standard.

Fatwallet.com is a 'deal' site that notifies me when oil is on sale. I usually pay about $3/qt, and about $4 a filter.

I have not confirmed by testing the oil that my schedule is OK, but I feel reasonably comfortable with it since it about matches Toyota's European Prius recommendations.

 

We see this subject periodically on the Yahoo groups. The trouble is that distance isn't actually a great indicator of how often to change oil. Nor is time, really. It all depends on how much driving you do in what conditions.

For a complete review of the subject, see the Engine Oil Bible on CarBibles.com. I'll try to summarize:

The engine oil's job is to lubricate - duh. It also collects the following:

• Bits of metal that do get worn off (ferrous bits collect on a magnet, and big bits are filtered by the filter, but the rest stays in suspension)
• Water from condensation in the engine and from combustion
• Other chemicals such as acids formed by combustion or mixing with exhaust materials

The change in colour commonly isn't damage to the lubricant itself - although that does deteriorate over time - but simply it gets more opaque due to all the other stuff floating in it.

The author says:

"the optimum time for changing oil ought to be related to a number of factors, of which distance travelled is probably one of the least important in most cases. Here is my selection in rough order of importance:

1. Number of cold starts (more condensation in a cold engine)
2. Ambient temperature (how long before warm enough to stop serious condensation)
3. Effectiveness of crank case scavenging (more of that anon)
4. State of wear of the engine (piston blow-by multiplies the problem)
5. Accuracy of carburation during warm-up period (extra gook produced)
6. Distance travelled (well, lets get that one out of the way)"

Well, a US Prius has the coolant flask system. (The EU model reportedly does not.) That preheats the engine to a degree, but wouldn't eliminate any condensate already in there. But it should improve factor 2. I can't say anything about 3.

A Prius engine is very low-friction and low-compression (reportedly it can be turned over by hand), which should reduce wear, and the 100,000 mile reports tend to concentrate on battery and transmission rather than engine components! The very low toxic emissions on cold start tests attest to the accuracy of the fuel mixture, and the car deliberately performs a fast warmup. On that basis, the engine oil should generally last longer than in competitors.

Still, changing it more often is probably better than not.

Certainly Toyota GB suggests a 10,000 mile oil change, but only, really, because all their competitors do as well. Some competitors suggest 12,000 or 15,000 mile services sometimes, but this is often revised down after warranty claims! Toyota of Europe suggests 15,000km (9,000 miles) but again this is just a standard inter-service distance.

 

I go approximately 15000 miles between oil changes. I do this with 0W-30 Amsoil Synthetic, Amsoil Filter Changes, and regular oil analysis with the sample interval based on previous results. The following considerations factor into this:
1) What do professional lubrication experts do for very expensive machinery? ... They do the above (good oil, good maintenance, good monitoring.)
2) I do not want to dump cheap oil through my engine and into the environment at a high rate. (Everyone loses except the cheap oil makers.)
3) I want to base my car maintenance on solid engineering knowledge, not lawyer's recommendations. (I'm more focused on preventing a problem rather than ease of paperwork if one occurs.)

 

I am using Mobil 1 Synthetic 0W-30 and a Purolator filter changing it every 10,000 miles might extend it to 15,000 miles when car gets some miles on it..

$52.00 is high I pay:

5 quart jug mobil1 fully synthetic 0w-30 at Wal-mart = $26.00
1 purolator oil filter at Advance auto = $ 4.19
_________________________________________
Total = $32.00 (with tax)

It also only takes about 3.5 quarts of oil so you have about 1.5 quarts left over: so with three Jugs you can do 4 oil changes..

 

Hi butchbs1985, as you are doing UOA on long oil runs, please post the results on PriusChat if you are not doing so already. All such data are very welcome.

 

After the warranty expires, and then with oil analyses, sure. Before then you're risking voiding the engine warranty to save a total of, what, $100?

 

Agreed.

-Compared to the cost of other synthetics. Even those posted in this thread, Amsoil is more costly to use. I drive about 3,000 miles / month so my greatest benefit is that I don't have to change the oil so often. Once a month was killing me.
-My father and brother work at the Whiting, IN BP refinery around here so I give them all my old oil for recycling. They even include the synthetic oil in the recycling process though I'm not sure exactly how it works.
-IMHO, nobody should attempt such long drain intervals without doing a UOA frequently. The UOA's on my Intrepid detected a cracked block before it got bad enough to cause a breakdown / serious issues. The car was still under warranty so Dodge replaced the block and the service guy said 'thanks for keeping on top of maintenance'.

Oil Analyzers just changed their site so hopefully, I can get the older data. Worst case, I'll post the last report that I have.

 

Remember that in the US at least, if you keep up with the necessary documentation to prove that you are performing proper maintenance, you would be able to provide a very compelling case against voiding the warranty. Based on the Magnuson-Moss Act as I understand it.

In my conversations with Amsoil representatives, if the manufacturer can prove that any issue was caused by the Amsoil product, Amsoil will cover the cost of repair as long as proper testing / maintenance procedures were maintained (Amsoils recommended procedures). That is why I adhere to the recommended Amsoil procedures and am thus not worried about warranty coverage.

 

With regular synthetic 5W-30 Mobil 1 (i.e. not the EP Mobil 1 5W-30) I think one could pretty easily go 7500 miles. Here is the UOA on my Prius and Mobil 1 5W-30. As can be seen after 5,200 miles there was still plenty of TBN left and I wouldn't doubt a 7,500 change is fine. However, there is some recent doubt cast on Mobil 1 5W-30 as far as some of it's wear performance. Also a one year/10,000 mile change would seem to be pushing Mobil 1 5W-30 a bit too far, at least in my car with my driving style/usage.

To go that number of miles I would look to Mobil 1 EP 5W-30 if you are looking to stay with Mobil 1 or, for just about the top of the line oil, Amsoil SSO 0W-30. This oil being a 0W will have better extreme cold pumpability than a 5W oil, and this oil can go as far as 35,000 miles or one year in normal service, or 17,000 or one year in sever service. I would do a UOA to verify however.

If you are feeling more adventerous, you could use Amsoil ASM 0W-20 oil. This is what I have in my Prius and I plan on going one year on it. The lighter weight 20 oil will give slightly better cold weather flow properties and slightly better (< 1% or 2%) gas milage in cold weather. Several people here also use it year round and have posted UOA showing very good low levels of wear with this oil. For the NE USA it is certainly a good oil to use, although I would be more inclined to use 0W-30 if I lived in a warmer climate like FL or Az.

Mobil also offers 0W-20 and 0W-30 oils and by all reports they too are fine oils, although I'm not sure if they have the TBN like the Mobil EP or Amsoil oils to go more than 10,000 miles.

Rumple

 

I've not had any engine trouble with 7,500 mile changes in my other vehicles with Mobil1. I haven't done UOA on any of them but my impression has been that the difference between 5,000 and 7,500 isn't really substantial as long as the engine isn't using oil. My vehicles seem to invariably/uniformly get knocked out of service (salvage yard) at ~10 years/150,000 miles due to some sort of accident (or brand new, properly inflated, but defective Bridgestone tire that comes apart on the interstate...) so I can't tell you how well that would work past 150K unfortunately.

I usually do not go to 7,500 until I'm out of powertrain warranty...but I don't sweat 6,000+ miles on a change either.

 

Magnuson-Moss says (among other things) that the maker can't refuse to honor the warranty merely because you had someone other than a dealer perform the necessary maintenance. To avoid having an argument with the maker you still have to perform that maintenance and have to be able to show that it was done, with receipts, etc. Going beyond the maker's recommended oil change interval is one way of asking for a fight in a warranty service situation. You may win that fight, but the burden of proof will be on you.

Even if the oil itself were completely indestructible you would still need regular oil changes to remove accumulated combustion products, fuel, water, metal flakes, etc.

 

I used Mobil 1 EP 5w30 with mobil 1 filter. at 8000 mile, oil is dark but is reasonably ok. However, I change it anyway because I found that when the oil start getting dark, the mpg drop about 5-8mpg. So I change it anyway

 

Agreed. While I do continue to test the oil at every change and have thus far seen no issues, I do not intend to use that oil beyond the test point. Based on conversations with others, oil can go downhill quick so not worth risking problems.

 

I read somewhere, Mercedes oil change interval is 15k miles by using fully Synethic oil; I am not so sure about this. However, if it's true about Mercedes oil interval is 15k; I think the Prius also can.

 

The topic of oil change interval is a very hot and heated one. I personally run Mobil 1 0W-20 and the Toyota filter in my Prius - excellent used oil analysis up to 12 months and 16,000 km (The "normal" interval in the EU)

With my FJ, I run Mobil 1 0W-40 and Toyota filter, with excellent results

Remember the Toyota motor sludge case? Those motors were run on bargain-basement no-name oils, at the "recommended" 7,500 mile interval, with pretty bad results. Instead of Toyota requiring a better oil, they universally lowered the oil change interval to 6 months or 5,000 miles

There are cars in the EU that have a "normal" 24 month or 50,000 km service interval. Any shocking reports of motors exploding over there?

Mobil also stands behind their oil, especially the Mobil 1 lineup. When my Prius was still brand new, had *very* odd used oil analysis reports. Toyota Canada blamed my use of Mobil 1. Mobil got involved, we determined it was residue from the dealership oil, as a virgin sample was pretty awful

In the end, you can faithfully bring in your Prius every 6 months, have it serviced with the no-name mystery oil from the dealership tote bin, and probably have no issues for the duration of the engine warranty. I had some of that dealership crap tested, I wouldn't run it in a lawnmower

Once you're off warranty, they'll claim "TFB you"re SOL so KMA"

YMMV

 

This suggests that the use of an EBH will extend the intervals by reducing #1 and 2. Is this true?