By accessing this website, you acknowledge that Edmunds and its third party business partners may use cookies, pixels, and similar technologies to collect information about you and your interactions with the website as described in our
Privacy Statement, and you agree that your use of the website is subject to our
Visitor Agreement.
Comments
Thanks!
If we use 15k as a interval the numbers tell the story: oil filter @2.50 7 qts conventional @ 1.25= 11.25/15,000 or .00075 per mile lubricated.
oil filter @2.50, 7 qts synthetic @3.65=28.05/15,000=.00187 per mile lubricated.
If in fact conventional oil can do the job of synthetic: WHAT IS THERE NOT TO LIKE?
There are a fair amount of folks on this thread that think that because the courts have ruled hydro cracked petro products to be synthetic that it must be so!? You bring up a valid point, they still are not!
If you are refering to a leap in faith, the answer is no. When I first started using Mobil One app 600k miles ago, I did do oil analysis, tread lines. And every 15k the valve covers came off for a dealer adjustment of valves. So not only did the dealer do the 15k synthetic oil change, but in fact looked at the inner workings on a time and mileage basis, and also would have done whatever engine warranty. While I do have engines that now go 60k before a valve check, again they go in their at time and mileage basis. And the engine warranty work would have been done by the same dealer anyway. The dealer in the 4 vehicles that I and they did the 15k oil change intervals are not only clean but according to their mechanics showed almost no appreciable wear. I had one TLC that had app 250k miles on it and absolutely NO sludge! Does that mean that conventional oil can't go 250k miles!! Absolutely NOT!
The operative question is: can it go with conventional oil with a 15k oil change interval with NO sludge and no appreciable wear!!???
Fast forward to the GM 4178 or GM spec which Mobil One oil meets or exceeds, i.e., Corvette Z06. FACTORY recommendation is up to a max of 15k oil change intervals and/or one year. So no, it is not a leap at all!
Mobil has run many tests at 15K and 25K drains with good results. But can't recommend it due to vipers (lawyers). Amsoil of course says 25K/one year. People do it-apparently with OK results. Delvac 1 has tested theeir oil to 100K oil drain intervals in diesels. They specify 60K intervals.
In sumary-I just don't think you can make the leap of stating that SL oils are in the same class as PAO's . Does it make economic sense to use conventional SL's and will they offer adequate protection at normal change intervals??-sure. Some may be better than Mobil 1 at that interval bc they have higher levels of zinc and moly. Thats why I'm investigating Shaeffers.
Here is a link that gives a large # of oil analysis- I don't have the latest verson of -I believe Exel so I cant open it. Perhaps someone could download it and post some of the results- Say the Name of the oil, miles on the oil and Iron/lead content. I will do it next week when I visit my son who has the latest version.
http://forums.maxima.org/showthread.php?s&threadid=100060
Ther document is in compressed version at bottom of page.
7,981, Amsoil, 10W/30, 18, 6, 5, 8, 3, 10.1
Normal, Synthetic, 5W/30, 23, 8, 19, 20, 34, N/A
7,232, Redline, 10W/30, 18, 11, 19, 14, 75, 4.5
Normal Synthetic, 10W/30, 28, 8, 5, 17 28, N/A
12,000, Amsoil, 5W/30, 21, 42, 17, 8, 5, N/A
22,120, Amsoil, 5W/30, 40, 54, 25, 18, 7, N/A
Normal Synthetic, 5W/30, 26, 48, 10, 20, 6, N/A
3,270, Honda Factory, 5W/20, 60, 139, 11, 118, 9, 5.5
normal Synthetic, 5W/30, 23, 41, 9, 18, 5, N/A
5,600, Amsoil, 15W/40, 17, 10, 68, 7, 59, 7
11,155, Amsoil, 15W/40 14, 14, 4, 8, 26, 7.6
7,900, Amsoil, 15W/40 25, 16, 9, 7, 7 11.6
15,100, Amsoil, 15W/40, 15, 24, 18, 9, 9, 8.3
5,000, Amsoil, 20W/50, 14, 13, 10, 8, 6, 10
11,440, Amsoil, 20W/50, 12, 8, 12, 7, 6, 9.8
5,500, Amsoil, 10W/40, 8, 5, 7, 6, 3, 10.9
12,600, Amsoil, 10W/40, 13, 7, 14, 7, 5, 10.7
6,000, BMW Synthetic, 5W/30, 9, 5, 2, 8, 3, 8.8
Remember that TBN is a good indicator of whether the oil is bad. A a value of 2 or below indicates a bad oil. I wish they had tested TBN on the 22 k mile change. A value of 30 or higher iron is a problem. Comments indicate that the Honda (Iron=60) may not be a problem since it is on a new engine.
The normal's listed are for the type oil and engine that are listed in the analyses above that reference.
First of all NO oil manufacturer, synthetic or conventional guarantees the engine (warranty) !!!
In the Corvette Z06, the warranty language is VERY clear 3yr/36k BY Chevrolet. The oil change interval is up to 15,000 miles or 1 year. In that case the Corvette specification is the 4178 GM spec and Mobil One is among those that meet it. By anti trust law, you can not specify say Mobil One without providing it, hence the GM 4178 spec. So as long as the spec is met, you are meeting the spirit and intent of the law.
In the case of the TLC's, the service manager and asst service manager gave the nod for the engine warranty's on the 15k oil interval! As an aside, he knew and I knew that we would NOT fulfill on the 3yr/36k warranty on almost any major system let alone because of the 15k synthetic interval !!
While I don't necessarily advocate this, you can do an oil analysis almost at any juncture. But if you want a systematic cycle once near the end each interval would for practical purposes be alright. Again, you are really establishing a baseline and monitoring the treadline to help predict future maintenance items, fault isolation, and preventative maintenance for fleet integrity or in our cases seeing we are getting good wear characteristics.
When I used to over see the process for in excess of 200 fighter jet engines oil analysis, it was part of the periodics, and if we we were having specific problems we would do oil analysis as needed or as directed.
>:^[
In the case of the Corvette, to meet warranty concerns I don't have much of a choice!
A while back, I asked if the Chevron SL met the General Motors 4178 specification. It would be way less costly to me if the Chevron SL did meet that specification. As cited in this forum, the app cost is 1-1.50 dollars (I have seen Chevron SL at a Costco 12 qts for 10.99) vs 4-5 dollars a qt for Mobil One synthetic.
It does baffle me somewhat that the folks who claim the cost of oil is a drop in the bucket compared to a new engine are willing to leave the oil in for so long. If the more-expensive synthetic oil is 'cheap insurance' then why not add an extra measure of insurance by changing the oil slightly more often?
I guess I have been hit over the head with the 'change your oil every 3,000 miles' mantra in this country that I would never be comfortable leaving oil in an engine for 15,000 miles or more, no matter what the oil analysis showed.
So the hypnotic "change your oil every 3000 miles" advertising works eh?
Of course every car and driver etc has its baseline! That is really the reason for the oil analysis. It confirms or denys what you can intuitively see feel or know!! Or even shows and tells you things you didnt even want to know!! Frankly, I thought that was a given. As a practical matter whatever it is with conventional oil 3k,4k, 5k, etc. Synthetic oil ie Mobil One can safely be used up to 3x over conventional. So in my case if I used conventional oil I would use a 5k interval.
If one is not comfortable with it, as a Chevron stockholder why would I discourage you from buy more of this product and at more frequent intervals?
For me its the oil drain thing. With 6 cars I maintain and 4 of those are some distance away (400 miles) its a convenience thing and not a money thing. Besides after 6-10K miles there is virtually no oxidation with syn and the oil will still be capable of performing to an extra margin of safety over conventional oils. Its like Painting your house every year. Its not necessary. But I will give you-2k drain intervals would be better than 6-10K-just not a whole lot better.
ruking: I try hard to get that 3,000 mile marketing out of my head, but it's hard! Actually I'll probably go with a 3,500-4,000 mile change interval once I switch to the Chevron and Citgo hydrocracked SL oils. Right now with Mobil 1, I'm changing every 5-6k miles. I'm tired of dumping an extra 2 quarts into our Isuzu Trooper during that change interval, though!
I can understand!
The TLC's use between 1/4 to 1/2 qt (normally 1/4 qt) at the 14,000 mile mark with a 15k oil change interval. So it is six of one, half dozen of the other if I top up or just let it go till the oil change!
The GM product used app 1 qt per 5k miles. I am told this is EXTREMELY good for a high performance type engine.
#4074
With an SL rated synthetic, i.e., Mobil One I would not have a problem with going 22,500 miles with a conventional SL rated oil good to go to 7,500 (baseline).
Actually, the engines are alright with it. I am just here to deal with the aftermath!! (I foot the bills, and for engine damage due to synthetic vs conventional ie longer oil change intervals: NONE!!)
I am actually ok with it under the old SJ rating! While I understand that the SL rating is far stricter, ie the oil is better than the old SJ rating I am assuming that the conventional to synthetic relationships have not changed given a better baseline of the SL conventional oils.
What about Quaker State?
Possibilities--
1. There's a loophole that get them out of repairs.
2. Any SL oil can allow a car to get 250K on the engine if you do 4000 mile changes.
3. 99% of the time, the rest of the car craps out before the engine does anyway.
Again, if specs. are any indication, QS's specs are inferior to Pennzoil and even slightly inferior to SuperTech. The warranty applies to all Quaker State oils, including dino.
From their web page:
" Either when you purchase a Quaker State® oil change or change your own oil with Quaker State®, Quaker State will give you a FREE limited warranty that will protect all your engine's lubrication-related parts, such as the pistons, timing chain, valve stems and cam shafts, for 10 years or 250,000 miles.
How to get coverage.
To qualify for coverage all you have to do is get a Quaker State® oil change. Your engine must have less than 36,000 miles and have been manufactured within the last 48 months. It's that easy!
How to keep it.
Just get a Quaker State® oil change at a retail service center every 4,000 miles, or 4 months, whichever comes sooner. This may not be the same as some vehicle manufacturers recommend, but neither is the length of our limited warranty. The oil filter and air cleaner elements must be replaced and the emission control system must be maintained in accordance with the vehicle manufacturer's recommendations. You have to take very good care of your engine if you want it to last for ten years. Or 250,000 miles. Our Limited Warranty is Transferable. The Quaker State® limited warranty offers something that could prove valuable if you sell your vehicle before it's gone 75,000 miles. The limited warranty can be transferred to the next owner.
And It Isn't Hard To Follow.
Recent research found that at least 80 percent of those who enrolled found it easy to follow and met the requirements of this program.
How to Enroll.
Simply fill out and submit our on-line application. The Quaker State® limited warranty is only available in the United States and Canada. For full details on this Limited Warranty Program, call 1-800-677-6457 and switch to Quaker State® oils and greases that take better care of your engine!
Quaker State Warranty Headquarters
P.O. Box 5167
Buffalo, New York 14240-5167
1-800-677-6457 "
In otherwords it's a very easy guarantee to make.
That would be a good warranty if it was at 15k oil change intervals!
While I stand corrected, if they do not use the normal loopholes to get out of paying for those repairs,(biggerst one is can you prove that the oil caused the needed repair) perhaps all those new Toyota Sienna owners that experienced sludge problems could use a warranty like this? (Even Toyota is using any and all loopholes to try to get out of this one!!)
Not to mention the fact that Quaker State, if I read your quote correctly is giving a longer engine guarantee than the folks that have manufactured the engine!!??
The other was a 2 liter Plymouth Arrow that I cooked because of coolent leaking problems. Early 80's and I probably had about 100K on it.
The third was a Festiva that gave up the ghost at 110K. Put a junkyard engine with 60K in it and the engine was still going strong at 160K, no oil burning whatsoever. Synchros were beginning to go, and it needed a major brake job so I (again) donated it. The original engine had probably only gotten one oil change in the first 28K (at which point I bought it). Still wish I'd held onto that car.
Everything else, including two Fiats and two Renaults was fine in the engine department when I unloaded them, with the possible exception of a mid sixties Corvair that had every system malfunctioning.
A quick count: 23 cars and 4 motorcycles. Many driven into the ground. Something was usually wrong that caused me to unload them. Three out of 27 equals 11% of my vehicles that had engine failures. One of the three engines was replaced and another 50K put on the car. Another died at the same time a transmission went, so I would probably unloaded anyway. Only one car or 3% of my vehicles was a total engine failure and that was my fault for trying to nurse a coolant leak.
I suspect that my experiences are rather typical, and that Quaker State's odds in offering that warranty is pretty good.
Would synthetic protected the valve guides in my Caravan? I've always heard that the valve guides in 3 liter Mitsu engines crap out at about 100K anyway. Would Quaker State pay for new valve guides? Good question.
I also doubt that you would get 10% increase with syn. 3% is the best you can probably expect. Not saying it ain't so; but there may be a tendency to drive better to have it happen-sort of like a self-fullfilling prophecy.
Correct me if I am wrong but we haven't seen any evidence at all of SL oil performance at any interval level-except for Shaeffers?
I've seen mobilones at 6k or 5k that where real close to needing to be changed out
I have seen a number of reports-what makes you say it was real real close to needing changing?? Most that I have seen had real good TBN's, and zinc levels were fine(including mine)
Anyway I'm not really here for one-upsmanship. I am locked in on syns. I am really trying to find the best. Right now I'm inclined to either do the Delvac 1, Shaeffer's Full syn with moly, or Mobil 1/Amsoil 10W with Shaeffer's moly #132. Really looking at my Sentra Oil analysis it will go 10K, but I think with some moly I can get further with less wear.
I know armtdm has done oil analysis for long periods of time with extended drain intervals. As I recall he has honed in on about 10K. Thats more support for the 3X time interval you are searching for. I would ask him to share some of that information. Perhaps someone can share some oil analysis on any SL oils? for even 3K