synthetic oil change interval

whodat · 03-19-2008, 11:50 PM

What's the latest data on the optimal synthetic oil change interval? I read some previous posts where some did synthetic oil analysis beyond the 5K miles interval and the synthetic oil was still good. Does anyone have some (new) data to share?

Thanks
Dave

**efusco** · 03-20-2008, 01:31 AM

http://priuschat.com/forums/care-mai...intervals.html

Attached is my 10k report

whodat · 03-20-2008, 11:36 AM

Hi Evan,
Interesting Blackstone oil report.

This data is based on 3 quarts of engine oil (not 3.5 quarts). Is that correct?

The comment from the Blackstone engine oil analysis that your "Prius is doing quite a bit better than most we have tested" - I wonder whether Blackstone is comparing other Priuses, or more generally other cars (including non-Priuses)?

Your driving style may effect this engine oil analysis. Does your driving pattern involve frequent cold engine turn ons (i.e. parked for an hour or more) or do you drive a long distance twice a day (to and from work) where the conditions of a cold engine is turned on only twice a day? Do you use a engine heater that pre-heats the engine before you start it? I am just trying to understand how I should extrapolate your results to my Prius that I start typically twice a day and do a 100 mile daily commute (roundtrip). I live near the coast in California so it rarely freezes in Winter and my Prius is kept in the garage overnight, although the garage temperature can drop to 40F.

I really appreciate you sharing the data.
Thanks
Dave

****Blackstone Oil Analysis Report Comments*****
"EVAN: We suggested trying 8,000 miles and you chose a 10,000-mile oil change, but your 1.5L Toyota took that oil
run in stride. There was only a minor increase in aluminum and iron while lead stayed the same. All of the wear metals
read dead on to the universal averages for this type of 4-cylinder, which are based on a 6,700-mile oil run. So, your
Prius is doing quite a bit better than most we have tested. The TBN was 2.4, showing some active additive left. Try
~12,000 miles for your next oil change and check back for another look at wear."

**efusco** · 03-20-2008, 12:18 PM

Quote:

Originally Posted by whodat

Hi Evan,
Interesting Blackstone oil report.

This data is based on 3 quarts of engine oil (not 3.5 quarts). Is that correct?

The comment from the Blackstone engine oil analysis that your "Prius is doing quite a bit better than most we have tested" - I wonder whether Blackstone is comparing other Priuses, or more generally other cars (including non-Priuses)?

Your driving style may effect this engine oil analysis. Does your driving pattern involve frequent cold engine turn ons (i.e. parked for an hour or more) or do you drive a long distance twice a day (to and from work) where the conditions of a cold engine is turned on only twice a day? Do you use a engine heater that pre-heats the engine before you start it? I am just trying to understand how I should extrapolate your results to my Prius that I start typically twice a day and do a 100 mile daily commute (roundtrip). I live near the coast in California so it rarely freezes in Winter and my Prius is kept in the garage overnight, although the garage temperature can drop to 40F.

I really appreciate you sharing the data.
Thanks
Dave

Hi Dave,
Your insight into this is accurate and thoughtful.
I have INfrequent cold starts as I us an Engine Block heater both at home and at work.
I use around 3 1/4 to 3.5 quarts of oil when I change...usually closer to 3.5.
My commute is ~15 miles and my speed never exceeds 40mph, I tend to P&G and my ICE on time is usually about 33-40% (depends how cold it is, traffic and how careful I'm being). I usually have at least 150 miles of highway miles per tank...my best tanks are the ones that I have no highway trips...so it's not exclusively commute driving. I also do some shorter (5 miles) trips to pick up kids and run errands closer to home each tank.

While I suspect the 100 mile commute would also be pretty easy on the oil since it means fewer cold starts it's certainly reasonable to take it 5k-7.5k, get a UOA done and see where you are....but I think you're going to find you can easily go 10k...remember, that's the recommendation in Europe for the Prius.

Boo · 03-20-2008, 12:44 PM

In my case, I wonder what effect time and New York City weather changes have on the oil.

I use Mobil 1 and wouldn't mind changing my oil every 5000 or 10,000 miles. But I don't drive much --- in 13 months, I have fewer than 3000 miles on the car (and less than 2000 miles since I did my first and only oil change with Mobil 1 at the 1000 mile mark).

In terms of time only, how many months can I go before needing to change my Mobil 1 oil?

Any thoughts would be greatly appreciated.

whodat · 03-20-2008, 01:37 PM

Quote:

Originally Posted by efusco

Hi Dave,
While I suspect the 100 mile commute would also be pretty easy on the oil since it means fewer cold starts it's certainly reasonable to take it 5k-7.5k, get a UOA done and see where you are....but I think you're going to find you can easily go 10k...remember, that's the recommendation in Europe for the Prius.

Just to be explicit, the 10K recommendation in Europe for the Prius is for non-sythetic or synthetic oil?

I have read that american oil (non-synthetic) can be of inferior quality relative to the standards of european (non-synthetic) oil.

Thanks
Dave

**efusco** · 03-20-2008, 03:05 PM

Quote:

Originally Posted by whodat

Just to be explicit, the 10K recommendation in Europe for the Prius is for non-sythetic or synthetic oil?

I have read that american oil (non-synthetic) can be of inferior quality relative to the standards of european (non-synthetic) oil.

Thanks
Dave

AFAIK it's for non-synth or not specified.

dogfriend · 03-20-2008, 03:31 PM

Quote:

Originally Posted by Boo

I

In terms of time only, how many months can I go before needing to change my Mobil 1 oil?

Any thoughts would be greatly appreciated.

I have a Ford Explorer that I have only driven about 1k per year for the last two years. I use Mobil 1 in the Explorer and change once a year. Even with low mileage, water and other contamination can accumulate in the crankcase.

BTW Toyota recommends 5k or 6mos, whichever comes first for the US Prius.

I think the European Prius recommendation is 10k or 12 mos. Maybe someone can confirm or refute this?

UOA of course is the best way to tell, because it will be specific to your car and your local driving conditions.

Boo · 03-20-2008, 03:51 PM

Thanks Dogfriend. Yeah I knew about the "whichever comes first" business. But I'm still doubtful about that advice in general, and with respect to synthetic oil in particular. I think I'm going to do what you do with your 1000 miles a year Explorer -- change the synthetic oil once a year.

Hara · 03-21-2008, 09:28 AM

In Europe we have 15k km / one year oil change interval. So, it's around 9300 miles.

I think that there is no recommendation in between organic and synthetic oil. There is only a requirement to fullfill API SL or SM standard.

03-19-2008, 11:50 PM	#1
whodat Member Join Date: May 2006 Location: Aptos, CA Posts: 73 My Car: 2006 Prius Model: Package: #8 Thanks: 1 Thanked 0 Times in 0 Posts Friends: 0	synthetic oil change interval What's the latest data on the optimal synthetic oil change interval? I read some previous posts where some did synthetic oil analysis beyond the 5K miles interval and the synthetic oil was still good. Does anyone have some (new) data to share? Thanks Dave

03-20-2008, 11:36 AM	#3
whodat Member Join Date: May 2006 Location: Aptos, CA Posts: 73 My Car: 2006 Prius Model: Package: #8 Thanks: 1 Thanked 0 Times in 0 Posts Friends: 0	Re: synthetic oil change interval Hi Evan, Interesting Blackstone oil report. This data is based on 3 quarts of engine oil (not 3.5 quarts). Is that correct? The comment from the Blackstone engine oil analysis that your "Prius is doing quite a bit better than most we have tested" - I wonder whether Blackstone is comparing other Priuses, or more generally other cars (including non-Priuses)? Your driving style may effect this engine oil analysis. Does your driving pattern involve frequent cold engine turn ons (i.e. parked for an hour or more) or do you drive a long distance twice a day (to and from work) where the conditions of a cold engine is turned on only twice a day? Do you use a engine heater that pre-heats the engine before you start it? I am just trying to understand how I should extrapolate your results to my Prius that I start typically twice a day and do a 100 mile daily commute (roundtrip). I live near the coast in California so it rarely freezes in Winter and my Prius is kept in the garage overnight, although the garage temperature can drop to 40F. I really appreciate you sharing the data. Thanks Dave **Blackstone Oil Analysis Report Comments*** "EVAN: We suggested trying 8,000 miles and you chose a 10,000-mile oil change, but your 1.5L Toyota took that oil run in stride. There was only a minor increase in aluminum and iron while lead stayed the same. All of the wear metals read dead on to the universal averages for this type of 4-cylinder, which are based on a 6,700-mile oil run. So, your Prius is doing quite a bit better than most we have tested. The TBN was 2.4, showing some active additive left. Try ~12,000 miles for your next oil change and check back for another look at wear."

03-20-2008, 12:44 PM	#5
Boo Boola Boola Member Join Date: Feb 2007 Location: New York, NY Posts: 4,286 My Car: 2007 Prius Model: Package: #2 Thanks: 166 Thanked 301 Times in 154 Posts Friends: 22	Time (not miles) for synthetic oil change interval In my case, I wonder what effect time and New York City weather changes have on the oil. I use Mobil 1 and wouldn't mind changing my oil every 5000 or 10,000 miles. But I don't drive much --- in 13 months, I have fewer than 3000 miles on the car (and less than 2000 miles since I did my first and only oil change with Mobil 1 at the 1000 mile mark). In terms of time only, how many months can I go before needing to change my Mobil 1 oil? Any thoughts would be greatly appreciated. __________________ Best regards, Tom 07 Magnetic Gray #2 - GY TripleTreds 195/60R15, BT Tech Stiffening Plate & Strut Tower Brace, Philips X-Treme Power Headlights, Webasto 4300 Sunroof, Sharkfin Antenna, Chrome Wheelskins Wheel Covers & Door Handles, BumperDefender.com Bumper Guard Strips, Body Side Moldings & Rear Bumper Protector, NoBump.com License Plate Screw Bumpers, Bumper Bully, Sheepskin Seat Cover, Leather Steering Wheel Cover, Leather Center Console Cover, Center-Hump Litter Basket, Non-Slip Pads, Dalmatian Bobble Heads.

03-20-2008, 03:51 PM	#9
Boo Boola Boola Member Join Date: Feb 2007 Location: New York, NY Posts: 4,286 My Car: 2007 Prius Model: Package: #2 Thanks: 166 Thanked 301 Times in 154 Posts Friends: 22	Re: synthetic oil change interval Thanks Dogfriend. Yeah I knew about the "whichever comes first" business. But I'm still doubtful about that advice in general, and with respect to synthetic oil in particular. I think I'm going to do what you do with your 1000 miles a year Explorer -- change the synthetic oil once a year.

03-21-2008, 09:28 AM	#10
Hara Junior Member Join Date: Nov 2007 Location: Finland Posts: 6 My Car: 2008 Prius Model: Package: N/A Thanks: 0 Thanked 0 Times in 0 Posts Friends: 0	Re: synthetic oil change interval In Europe we have 15k km / one year oil change interval. So, it's around 9300 miles. I think that there is no recommendation in between organic and synthetic oil. There is only a requirement to fullfill API SL or SM standard.