Oil change questions: time vs. mileage, mix synthetic and regular?

<div class='quotetop'>QUOTE(Doug Van Cleve @ Dec 26 2006, 08:04 PM) [snapback]367010[/snapback]</div>

The service schedule calls for an oil and filter change every 5,000 miles or 6 months, whichever comes first.

 

<div class='quotetop'>QUOTE(Doug Van Cleve @ Dec 27 2006, 01:04 AM) [snapback]367010[/snapback]</div>

I don't think I would be the one mixing regular and synthetic oil. They sell premixed semi-synthetic oil. In my opinion it is for people who can't decide. I think either stick with regular oil and save the money, or switch to fully synthetic oil and get the complete benefits it can provide. I have heard that synthetic oil won't drain back as quickly, so hopefully it will remain on the cylinder walls longer than regular oil. Jayman can correct me if I'm wrong about that benefit.

I changed the oil at 980 miles in my 2006 Prius, because it had been six months. The oil analysis said that it had high levels of silicon (104 when the average is 14) and wear byproducts (which I guess is copper which showed 34 when the average is 1), so I was happy that I changed it then. According to them it was as if the oil had 6700 miles on it if you just looked at the contaminant levels. The At that time I also switched to Mobil1 (synthetic) 5W-30 oil. I too am staying with the Toyota filters, just to avoid any potential conflict should a warranty issue arise.

 

<div class='quotetop'>QUOTE(sub3marathonman @ Dec 27 2006, 08:38 PM) [snapback]367460[/snapback]</div>

Where do you get an oil analysis done?
I just posted a question about using Duralube.

 

Awhile back tochatihu recommended Blackstone Labs. It costs $20 for the basic analysis and $30 if you want the TBN. On my first oil change with the 2006 Prius I went with the $30 analysis. There has been some previous talk about a Priuschat group purchase for these analyses, since everyone could save a bit of money. I haven't heard anything lately about this though.

Their address is 416 East Pettit Avenue Fort Wayne IN 46806 and the phone number is 260.744.2380.
Their website is http://www.blackstone-labs.com/ and you can order the free test kit there.

 

<div class='quotetop'>QUOTE(ShelbyN @ Dec 27 2006, 10:54 PM) [snapback]367501[/snapback]</div>

Most auto parts stores have oil testing kits available. You fill out some paperwork, fill one container with old oil, one with the same oil new, and send it in to the address on the paperwork. I got one at a NAPA parts store.

Harry

 

I know all vehicle manufactures use mileage and time, whichever happens first. But think about this....time doesn't seem to matter while the vehicle sits on the dealership lot. It only seems to matter after you purchase it.

This tells me time isn't that big of a factor and the only reason I change my oil based on mileage. But if the vehicle isn't driven much, then I will change it once a year.