12002 miles on Mobil 1 0w20, used oil analysis

Edit: (12/11/2009) See the update at the end of this thread, I would be careful going more than 10,000 miles on a single oil change and would recommend Renewable Lubricants Inc 0w20 if attempting extended oil change intervals. Also used oil analysis by Dyson Analysis is recommended.

Original post is below:

For anyone considering Mobil 1 0w20, my results have been pretty good for the last 7 months/ 12000 miles.
Drives are mostly shorter trips 10-15 miles with longer 90 mile weekend trips for skiing and occasional trips of 250 miles to Massachusetts from Maine and one trip to Ottawa from Maine (3 trips total).

Code:

Blackstone Labs Oil Analyses for 2004 Prius                                 
 
All samples pulled through dipstick, oil has not been changed since                                
Sept 2006. Will continue to analyze every 2000 miles up to one year.                                
Approx 53.9 mpg over 12002 miles or 222.7 gallons 87 octane                                
oil filter Mobil 1, air filter is OEM                                 
Oil Type    Mobil 1 0W20 SM GF4                            
Oil placed in service 9/26/06 at 50455 miles                                
 
Date______        5/4__    4/3__    2/11_    12/23    11/13    5/4__    
Year______        2007_    2007_    2007_    2006_    2006_    2007_    
Makeup oil        0.25_    0.625    0.125    0____    0____    Univ_    
Mi on Eng_        62457    60465    57983    55358    52834    Avg__    VOA
Mi on Oil_        12002    10010    7528_    4903_    2379_    6800_    0
Aluminum__        4____    4____    4____    3____    2____    3____    0
Chromium__        0____    0____    0____    0____    0____    0____    0
Iron______        12___    9____    8____    5____    1____    8____    1
Copper____        1____    1____    1____    1____    0____    1____    0
Lead______        0____    0____    0____    0____    0____    0____    0
Tin_______        1____    1____    0____    0____    0____    0____    0
Molybdenum        100__    94___    88___    94___    91___    65___    93
Nickel____        0____    0____    0____    0____    0____    0____    0
Manganese_        1____    0____    0____    0____    0____    1____    0
Silver____        0____    0____    0____    0____    0____    0____    0
Titanium__        0____    0____    0____    0____    0____    0____    0
Potassium_        1____    1____    1____    0____    0____    1____    1
Boron_____        43___    42___    40___    47___    51___    60___    74
Silicon___        13___    11___    11___    12___    12___    14___    3
Sodium____        6____    6____    3____    5____    4____    7____    4
Calcium___        2456_    2234_    2210_    2273_    2220_    2341_    2080
Magnesium_        16___    13___    12___    11___    11___    32___    13
Phosphorus        668__    636__    599__    631__    613__    628__    770
Zinc______        806__    774__    700__    739__    720__    725__    871
Barium____        0____    0____    0____    0____    0____    0____    0
ViscSUS210        51.9_    52___    51.5_    53.9_    52.2_    53-59    54
Flashpoint        370__    400__    370__    365__    370__    >355_    440
Fuel %____        <0.5_    <0.5_    <0.5_    <0.5_    <0.5_    <2.0_    
Antifrze %        0.0__    0.0__    0.0__    0.0__    0.0__    0.0__    
Water %___        0.0__    0.0__    0.0__    0.0__    0.0__    <0.1_    
Insolubl %        0.3__    0.3__    0.2__    0.4__    0.2__    <0.6_    
TBN_______        3.4__    4.4__    4.6__    2.9__    8.6__    _____    9.9
 
TBN of 2.9 was probably in error, 4.6 result rechecked twice (4.5, 4.7)                                
1/8 quart (4 oz ) Mobil 1 0W20 added 1/11/2006                                
5/8 quart (20 oz) Mobil 1 0W20 added mid Feb 2007                                
1/4 quart (8 oz) Mobil 1 0w20 added 4/3/2007                                
 

 

<div class='quotetop'>QUOTE(FireEngineer @ May 11 2007, 09:05 AM) [snapback]439831[/snapback]</div>

Not really. The iron typically rises with mileage. At 12 K I am seeing 12 ppm Fe, at 5 K it was 5 ppm so there seems to be a gradual increase of 1 ppm per 1000 miles. Now that the warmer weather has finally arrived in Maine the wear will probably be even lower as much of the wear is due to cold startups (it stayed relatively cold here through most of April.) There is some inconsistency in the rate of increase of iron from sample to sample, but some of this is likely due to margins of error in the results. As long as I don't see a big change in the overall trend in wear metals, the TBN stays above 1.9, and the insolubles stay under control (less than 0.6), I plan to keep running the oil for a year and test every 2000 miles.

Edit: 12/11/2009 Test was ended at 15000 miles, later I managed 20000 miles, but only with a 2 quart drain and refill at 10000 miles and using a different oil (RLI 0w20).

Dennis

 

Did you notice any difference in Fuel economy with the GC?

 

<div class='quotetop'>QUOTE(bruceha_2000 @ May 15 2007, 04:18 PM) [snapback]442696[/snapback]</div>

Actually your powertrain warranty is 60000 miles, so you should stick with 5k. It isn't necessary to do a used oil analysis as often as I have, I am just showing people what is possible in a Prius. If you are interested in extended oil change intervals, I think 10000 is safe with a good full synthetic. You could take a sample at 10k and continue running the oil if the analysis looks good (maybe for another 5k) or you could just change every 10k and skip the analysis. In Europe the oil change interval is 16000 km (10000 miles), so I am confident that if you use a ACEA 1 oil (most full synthetics meet this spec) 10k will be fine. You can stick with 5k until October when I have finished my test and see how far I can go. I will stop at 1 year or when the oil is used up (low TBN).

Edit 12/9/2009:

Due to inherent fuel dilution problems with the gen 2 prius, I think 5k ocis make more sense unless guided by oil analysis. Also Blackstone was not seeing the fuel dilution that Dyson Analysis detected so even oil analysis might not be enough, so I would stick with 5k oil change intervals to protect my engine.

Dennis

 

<div class='quotetop'>QUOTE(bruceha_2000 @ May 19 2007, 10:07 PM) [snapback]445921[/snapback]</div>

My signature has not been updated for a while but my average for the last 6 months has been 53.1 MPG and 58.3 MPG for the past year. The low point this winter for a 12 tank average (about 3 months) was 50.5 MPG (12/22/06 to 3/15/07). I do a couple of things in winter to help improve fuel economy. I use a block heater and I block the front grill to keep the engine warm. Without these tricks (and others below), last winter's low point for 12 tank average was 46.8 mpg on 3/13/06. Since May 16, 2006 I have been really trying to get good fuel economy by using pulse and glide where possible, by avoiding the interstate where practical, and just generally slowing down, anticipating stops and lights and following general good fuel economy habits without being a nuisance to other drivers. Normally I make short trips of about 10-15 miles on lightly traveled roads with very little traffic, from what I have seen of Vermont, the roads here are probably very similar to yours, but I don't live in the mountains so my terrain is not very hilly (mostly small rolling hills). I make weekend trips to Sugarloaf in the winter (about 85 miles), trips to my camp (about 35 miles) in summer, and 2 or 3 trips a year to Massachusetts (250 miles), I drive about 20k per year. There has been a noticeable increase in fuel economy by doing the pulse and glide, the block heater, grill block, and minimizing highway driving (I have also increased tire pressure to 48F/46R from 42F/40R and switched to M1 0w20 from M1 5w30), the rest of the stuff I was doing already. Last May 16 my 12 month avg was 51.4 mpg, May 14, 2007 it is 58.3 mpg. There is a much bigger fuel economy improvement in warm weather with these techniques. In 2005 my highest 12 tank avg was 54.0 mpg in October, in 2006 it was 67.0 mpg. If you are interested in this stuff check out cleanmpg, now would be the time to try it because you really see results and it is encouraging. It's also nice to be getting 60 mpg or better when prices are $3+/gallon.

Dennis

 

The tires are Michelin Energy MVX Plus with 44 psi max pressure, lately I have reduced the pressure to smooth out the ride, but last summer I think I went as high as 54 psi on my almost worn out Integrities. There is a big margin of safety built into that 44 psi max. Some fanatics run the tires at 60 psi and up to improve fuel economy. They need to see the dentist a lot though cause their fillings come loose . Low pressure is usually less safe than high pressure, remember those Ford Explorer blowouts, those were due to the manufacturer recommending too low a pressure for the tires. Running at 44F/42R is perfectly safe even on the crappy Integrities (probably safer than 38F/36R) and gives more even tire wear.

I would think the pulse and glide would work great around town in Vermont, but it's not for everyone. I think the grill block can stay in up to about 60 F from what I have read. I think 50 F would leave a pretty good safety margin. I still have most of my grill block in, I use the pipe insulation and have removed a couple of pieces from the lower grill (2 of 5) the upper two slots are also blocked. (I don't do a lot of high speed driving.) Now that it is finally warming up here I may remove it completely June 1st. The block heater install is a pain, any good mechanic would have no problem, unfortunately I am not a mechanic. You can order the part and just have your dealer install it, I don't think you need to go to Canada. The block heater helps a lot in the winter especially for the first 5 minutes. How fast do you drive on the highway? Slower driving will get you better mileage so 65 is better than 75 or 85.

Dennis

 

An update on the Prius and running extended oil changes. At 14000 miles I had my oil analysed by Dyson Analysis which found fuel dilution and much higher wear levels for iron and aluminum. I had the oil retested at 15000 miles by Blackstone labs (which had done all the previous analyses) and the wear levels were the same as 12000 miles with only a trace of fuel dilution.

I would no longer recommend extended drains on the Prius unless doing an analysis with Dyson Analysis. I would also recommend Renewable Lubricants Inc. (RLI) 0w20 if you want to take a chance on extended oil drain intervals without an analysis by Dyson analysis, but don't go beyond 10000 miles. I have stretched my drains as far as 20000 with a 2 quart drain and 2 quarts of fresh RLI at 10k, but I was curious to see how far I could go. At the time I was driving about 24k miles per year. I now have a 2010 Prius so the 2004 only will go 8-10k per year, I will take a sample at 6 months. I tried 5k on Pennzoil Platinum and things did not look that good after 5k.
Note that the attached file does not show the results from the Pennzoil Platinum oci, but gives results from one Mobil 1 analysis (at the bottom of the list) and several analyses of RLI 0w20 as explained in the next post.

 

Some notes on the uoa attached to the previous post. The analysis from june 2007 was on Mobil 1 0w20 at 14000 miles and was another in the series of uoas from Blackstone, i.e. the same oci was analyzed at 2500, 5000, 7500, 10000, 12000, and then 14000 mles. All other analyses were on RLI 0w20. The first oci was for 15k miles using an Amsoil EaO Oil filter with analyses at 5k,10k, and 15k. The pcv valve and air filter were changed at 5k and at 10k one quart of oil was pulled with an oil extractor thru the dipstick and a fresh quart of oil was added. The next oci used the same oil and filter type with analyses at 10k and 20k. At 10k 2 quarts of oil were pulled out and 2 fresh quarts were added.

 

I have added some comments to my previous posts in this thread and I am attaching the most recent analysis from my 2004 prius using Pennzoil Platinum 5w20. I have now switched back to RLI 0w20.