Oil change interval with synthetic oil

[DougSlug]

Got an oil change today at the dealer (15,000 mi). They had a note in their records to only add 3.5 qts--this was a result of a hassle I had with them the last time. I was happy to see that, and I didn't even have to give them the copy of the TSB I had in my hand ready to go!

At my previous (10,000 mi) change, I switched to synthetic. This time, I decided that since I was going to stick with a 5K interval anyway, there probably wasn't a big advantage in sticking with synthetic, and I could save money in the process. For this reason, I told them to use conventional oil this time.

Well, this raised a flag with the service desk person--she called over the service manager, who promptly told me that once I used synthetic, I could damage my engine if I switched back to dino oil. Since I was not well-armed to confirm or deny this allegation (and, frankly, I wanted to avoid another struggle with this service manager), I let them go ahead with the synthetic again this time, and planned on researching it when I got home (hello, PriusChat!).

So I am seeking educated and/or experienced answers to a couple of questions:

1. Is it "bad for the engine" to switch back to conventional after running 5,000 miles on synthetic? (I don't trust the advice of service managers, but I'll allow that sometimes they're right.)

2. With synthetic oil, does increasing the drain interval (say, to 7,500 miles) have any ill effects on either the engine or the warranty coverage?

Thanks,
Doug

[jayman]

1. No, an old woman's tale. Complete BS with modern synthetic oils. The early synthetics had different esters and PAO's that would act like a laxative and literally break the deposits loose.

2. Well, that is a touchy subject. The Prius operated in the EU has a normal 12 month or 10,000 mile oil change interval, using ACEA spec motor oils. To maintain warranty Toyota does require you to change your oil and filter every 6 months or 5,000 miles, no matter what oil you use

Considering that my used oil analysis of Mobil 1 0W-20 at 16,000 km was much better than the dealer oil run to only 5,000 km, something is clearly amiss. The dealer oil was also complete crap based on the virgin oil analysis

There have been heated debates on PriusChat over the benefits - and liabilities - of using synthetic oils. Tread with fear!

Given you live in NJ and experience cold winters - not as cold as mine - you would probably have benefits to running a synthetic at least in winter. For winter up here, I prefer to run only a synthetic 0W-30 or 0W-20.

Remember the SAE J300 specs for cold pumping only require a 5W-xx to be "good" down to -30 C. Many will actually test borderline at -25 C

[drifty1955]

Why are you going to the dealer for an oil change? To save $20? Whats wrong with the oil change places that don't even let you get out of your car? Its 5 minutes....as opposed to the circus of taking your car to the dealer for an oil change.. Go to a quickie lube...bring your own Mobil One oil....tell them its 3.5 quarts only.....they show you what they put in..give you back 1/2 quart..give them the factory oil filter its only $6......and $20 and 3 minutes later your out of there. There are all like a machine. Find one you like and always go there. And if concerned check the oil level 1/2 block later. You think the dealer does a better job with your piddling oil change job? Telling the dealer to use conventional oil is nuts. They'll give you conventional oil alright. All for what?...so you can save $ 30? If your so concerned with saving a tiny bit of money why did you buy this car? There's many many new cars for $ 10,000 less that will run just fine and get 30 mpg's all day long. I don't get it. This is not a cheap car.
The last 4 new cars I have owned never saw the inside of a dealer once. I avoid that like the plague. Only thing you have to do is put high quality fluids & oil in them keep them tuned and take it easy on them and most cars will run a long long time. I sold all of them for a profit. I expect to do the same with my Prius.

[lenjack]

No...avoid quickie lube joints. As for switching, this issue has been raised for 20 years. You may switch at will. No damage will occur. Conventionals and synthetics are completlely interchangeable and compatible, no matter what anyone says.

[DougSlug]

<div class='quotetop'>QUOTE(Drifty'sDad @ Nov 3 2007, 10:02 PM) [snapback]534487[/snapback]</div>

Why are you going to the dealer for an oil change? To save $20? Whats wrong with the oil change places that don't even let you get out of your car? Its 5 minutes....as opposed to the circus of taking your car to the dealer for an oil change.. Go to a quickie lube...bring your own Mobil One oil....tell them its 3.5 quarts only.....they show you what they put in..give you back 1/2 quart..give them the factory oil filter its only $6......and $20 and 3 minutes later your out of there. There are all like a machine. Find one you like and always go there. And if concerned check the oil level 1/2 block later. You think the dealer does a better job with your piddling oil change job? Telling the dealer to use conventional oil is nuts. They'll give you conventional oil alright. All for what?...so you can save $ 30? If your so concerned with saving a tiny bit of money why did you buy this car? There's many many new cars for $ 10,000 less that will run just fine and get 30 mpg's all day long. I don't get it. This is not a cheap car.
The last 4 new cars I have owned never saw the inside of a dealer once. I avoid that like the plague. Only thing you have to do is put high quality fluids & oil in them keep them tuned and take it easy on them and most cars will run a long long time. I sold all of them for a profit. I expect to do the same with my Prius.
[/b]

The issue isn't the money. Save your breath, Dad--it's well known that dealers aren't the cheapest places to get oil changes. My questions were related to the advantages/disadvantages of one type of oil vs. the other, etc. Specifically, if the oil change interval isn't going to be longer, are there other compelling reason to use synthetic? If not, why pay more for it? I think the answer is: there probably are other good reasons irrespective of change interval.

- Doug

<div class='quotetop'>QUOTE(lenjack @ Nov 3 2007, 10:07 PM) [snapback]534489[/snapback]</div>

No...avoid quickie lube joints. As for switching, this issue has been raised for 20 years. You may switch at will. No damage will occur. Conventionals and synthetics are completlely interchangeable and compatible, no matter what anyone says.
[/b]

If this is the case, then I can establish that the service manager gave me incorrect information that cost me extra money. I want to offer this feedback when I get the obligatory follow-up phone survey asking about my "service experience". See, I have a bone to pick with this particular service manager...she seems poorly informed on a number of issues. My bad experiences with her are pretty consistent now, to the point where I'm considering dumping that dealer for future service needs, and I think Toyota would want to know about that.

Thanks for the info.

- Doug

[drifty1955]

<div class='quotetop'>QUOTE(DougSlug @ Nov 3 2007, 10:31 PM) [snapback]534494[/snapback]</div>

The issue isn't the money. Save your breath, Dad--it's well known that dealers aren't the cheapest places to get oil changes. My questions were related to the advantages/disadvantages of one type of oil vs. the other, etc. Specifically, if the oil change interval isn't going to be longer, are there other compelling reason to use synthetic? If not, why pay more for it? I think the answer is: there probably are other good reasons irrespective of change interval.

- Doug
If this is the case, then I can establish that the service manager gave me incorrect information that cost me extra money. I want to offer this feedback when I get the obligatory follow-up phone survey asking about my "service experience". See, I have a bone to pick with this particular service manager...she seems poorly informed on a number of issues. My bad experiences with her are pretty consistent now, to the point where I'm considering dumping that dealer for future service needs, and I think Toyota would want to know about that.

Thanks for the info.

- Doug
[/b]

Sorry I thought the whole point of your post was to save money....and yes there are compelling reasons to use syn oil. If you have ever taken a valve cover off of a motor that has run 150k mile on syn oil and has absolutely no dino burn or the dark burnt sludge that you cannot scrape off the metal that says I have run my whole short life on cheap motor oil. A syn oil motor all you have to do is wipe off the oil with a rag and its usually pristene metal underneath. Bottom line its all about keeping it off the dealers rack. Thats a horror and mega $$$$. All you have to do is read posts here for a few weeks. Its full of people that don't pamper there cars and end up on the dreaded rack and wringing there hands that the "DEALER" is trying to screw them out of thousands. Wow..what a coincidence. Quality Oil changes are cheap. Toyota makes a superior motor. All it needs is superior lubrication. I understand that. The dealer does not want you to know that....because the dealer is your enemy.

[DougSlug]

<div class='quotetop'>QUOTE(Drifty'sDad @ Nov 3 2007, 09:46 PM) [snapback]534503[/snapback]</div>

Bottom line its all about keeping it off the dealers rack. Thats a horror and mega $$$$. All you have to do is read posts here for a few weeks. Its full of people that don't pamper there cars and end up on the dreaded rack and wringing there hands that the "DEALER" is trying to screw them out of thousands. Wow..what a coincidence. Quality Oil changes are cheap. Toyota makes a superior motor. All it needs is superior lubrication. I understand that. The dealer does not want you to know that....because the dealer is your enemy.
[/b]

Wow--your opinion of dealers is rather dark. Having said that, I tend to agree with your assessment!

But when it comes to repair, I think dealers will be better informed and better stocked for parts, especially for a more specialized car like the Prius. Oil changes, however--not a dealer specialty. Plus, finding a mechanic that you trust is challenging. I have heard (although not experienced first-hand) horror stories about quick lube joints that--at least in one case--resulted in damage, so I am not real comfortable with that idea.

Thanks for your insight on the synthetic vs. dino issue.

- Doug

[Rest]

<div class='quotetop'>QUOTE(DougSlug @ Nov 3 2007, 09:14 AM) [snapback]534332[/snapback]</div>

Well, this raised a flag with the service desk person--she called over the service manager, who promptly told me that once I used synthetic, I could damage my engine if I switched back to dino oil.[/b]

And did they tell you how it could damage your engine? Once again Stealership education at its best. I am amazed they would even say such a thing.....well not really. But no it, won't damage your engine.

[DougSlug]

<div class='quotetop'>QUOTE(Rest @ Nov 4 2007, 09:13 PM) [snapback]534769[/snapback]</div>

And did they tell you how it could damage your engine? Once again Stealership education at its best. I am amazed they would even say such a thing.....well not really. But no it, won't damage your engine.
[/b]

No, but I didn't ask, either. My experience with this particular service manager taught me that she wouldn't have known the answer, and she probably would have made one up to cover her ignorance. It was political at that point...I was pretty sure she was wrong, but, knowing that synthetic oil is a good thing after all, I didn't see the point of engaging her in another argument. There's a saying about arguing with fools...

- Doug

[Rest]

Why not just change your own oil? It is so freaking easy, takes less time than going to a stealership and will cost you less overall.