Extended Oil Changes

[dmccarty]

Moon,

</font><font color="blue" class="small">( This is by the onboard computer calculating the MPG not me. )</font>

I know my onboard computer MPG swings from 1 mpg over or under. Usually its at least .5 MPG off. On the high side. Which is wrong direction for it to be off...

The only way to really know your MPG is the old fashioned way of taking your mileage and actuall gallons put into the tank. There are still variables such as the level of the vehicle, foaming of the fuel, etc. But I figure those things average out over time.

When I switched to Shell 5wx40 I saw a small increase in MPG. But not enough by itself to justify spending more money on the oil. I do still use the 5x40 but not just for the increase MPG.

Later,
Dan

 

[Moon]

I agree. I do not do it because of the increased milage, but it is an added bennie. I never checked the way my on board computer calculated milage. But assuming it worked the same for the 1st 10k miles as it did after I changed to Mobil 1, it does show an increase. Now I'll have to actually calculate the next tank full the old fashioned way.
I usually don't trust things blindly, but for some reason I trusted the auto calculation. It seemed so simple, how could they mess it up?
When I first changed to Mobil 1 I saw a .5 MPG increase for a month or so. Next I checked when I was ready to do a change it was up considerably. I do not know how far back the computer goes to calculate the MPG automatically. I'll try to figure this out also and post the info here. It'll take a week er so to verify my numbers.

Moon of Ohio

 

[dmccarty]

Moon,

I think my trucks computer calculates based on the previous milages unless I reset it. I always reset it or at least I think I do. /forums/images/graemlins/grin.gif It goes to zero at least.

Some of the people on TheDieselStop have modified their fuel tank filler tubes so that they can be sure they are filling up the same every time. I'm not going that far. Figure it all averages out over time. /forums/images/graemlins/grin.gif But I try to be consistant on how I fill the tank.

I run synthetic to help cold weather starts, the increased mpg, and to cover my fanny when I forget or cannot change the oil. The last few months has been very hectic due to finishing our new house. My oil is supposed to be changed at 5,000 miles. I think I have gone as high as 6,200 miles on the oil. I get the oil anaylized for grins and giggles so I know I have been ok in extending the drain time. Well due to the new house the oil did not get changed until the 7,700 miles had passed on it.

The test report came in last night. I was ok on all of the oils related values. The TBN I think was still in the 9s. The wear values had not changed over the other oil changes. However they did find diesel fuel in the oil at 2%. It should be under 2%. This is the first time this has shown up. They said don't worry about it until we get the next sample. /forums/images/graemlins/blush.gif

I'm not really into extended drain times but I do think the synthetic is buying me a big of time/insurance if I can't change when I would like. I would have preferred to wait to change the oil the last time but I was worried about the milage on the oil. It was COLD outside and I was sick so I really did not want to crawl under the truck to change the oil. By the time I was done my hands and feet where numb and hurting from the cold. I would have like to have waited for slightly warmer weather. Now I know I can. /forums/images/graemlins/grin.gif

Later,
Dan

 

[gsxr1100]

Sounds good but I would need to see the number’s.

With only that few/little miles it should be good. The diesel fuel at 2% seems kind of high to me. So either you idle for very long times (without an idle controller), stop and start a lot, short trips or injector/computer issue. If you have fuel in the oil, your viscosity should have dropped or gone into next range. I would keep an eye on it. Also the fuel in the oil might or might not contribute to some high wear #’s.

Just keep an eye on it since I think the limit for concern is like 3% and some labs flag at 2%.

 

[dmccarty]

gxr1100,

I don't have the numbers handy but there was very little or no diiference with this last report vs the early reports many of which where done around the 5,000 mile mark.

The lab flags at 2% diesel. And they mentioned stop and go or short trips. It could be the stop and go traffic. Picking my daughter up from school was h...ll. There just was no way to avoid sitting in traffic for 15-20 minutes. But that was only once a day. The morning drive was pretty easy and at least once a week there would be the 60 mile drive on rural roads to the new house. But maybe that school traffic was the problem.

The stop and go traffic, or at least the worse of it should be over with since we are at the new house and a new road opened up near the school. Now that I think about it we just started at this school and I'm pretty sure that oil change comprises the start date of the school. That would explain why earlier reports did not show the fuel. Hmmm.

It will be interesting to see the next oil change report. /forums/images/graemlins/grin.gif

So far the wear numbers have not moved.

I'm glad I test the oil. /forums/images/graemlins/grin.gif

Later,
Dan