Amsoil v Mobil1

[Duke W.]

Re: Amsoil v Mobil1

If you go to www.api.org you can download the latest "oil spec card" that shows both the latest and old specs going way back for both C and S-catergory engine oils.

Some manufacturers also have good spec sheets on their specific products. I'm not trying to sell Delo (I have no brand preference, nor do I recommend or promote specfic brands), but they do have excellent spec sheets, and all same API spec oils will have very similar specifications and chemical analysis regardless of brand.

https://cglapps.chevron.com/msdspds/...age=&lbCompany=

Go to the Chevron Delo 400 LE 15W-40 LE link in English (on the second page) and click it.

Interestingly, this is a new spec sheet from the last time I looked at it. The P concentration is listed as .12% (1200 ppm) and Zn is .13%. Given that the CJ-4 P limit is 1100 ppm... go figure!

In any event, even if the P is 1100, which would make the Zn about 1200, these concentrations of P and Zn indicate a ZDDP concentration of about the same as pre-SL oils. SL was the first API spec oil to limit P, and the limit was 1000 ppm. Prior to this typical S-category oils had about 1200 ppm Zn, which is in the same ballpark as CJ-4.

Chevron, and other manufacturers also offer CI-4 (go down few columns of the above linked page to Chevron Delo 400 Multigrade and click for the spec sheet), but you may only find it in rural areas where there is a lot of farm equipment that still uses high sulfur diesel fuel. CI-4 has a bit more P/Zn, but the slighly lower level in CJ-4 is still more than adequate for vintage engines. CI-4 also has a higher TBN (total base number) to neutralize the acids that can form with high sulfur diesel fuel.

Low sulfer diesel fuel now has about the same sulfer concentration as gasoline, so the lower TBN of CJ-4 is okay for gasoline engines.

Duke

[Jeff B.]

Re: Amsoil v Mobil1

I have been hesitant to use synthetic oils in my untouched (now 52,000 mile) 1967, never rebuilt, 427 engine. I have always used Valvoline 10W-40 with no problems. As the API classifications changed, and oils were reformulated for better emmission control, I started to be concerned with the lowering of ZDDP levels. Consequently, about 10 years ago, whenever I changed oil, I would include 1 pint of the GM E.O.S. additive, and feel even when using today's "better" oils, everying is OK.

[Duke W.]

Re: Amsoil v Mobil1

Why not just use CJ-4? If you insist on Valvoline, they have one, too?

Duke

[Jeff B.]

Re: Amsoil v Mobil1

Why not just use CJ-4? If you insist on Valvoline, they have one, too?

Duke

That is probably what I will do when my current supply of 10W-40 runs out.

[George J.]

Re: Amsoil v Mobil1

Good question, George, and I'm not sure if I ever answered it directly.

Yes. In fact all engine oil additives are consumed with use, and the base stock oils slowly oxidize, which is why oil changes are necessary.

The level of additives in typical 15W-40 C-category oil are more than adequate for up to 7500 miles of normal service in a basically healthy engine with a properly functioning PCV system.

Back when I used some of my cars as daily drivers, I changed the oil and filter every 5000 miles, which was two to three times per year, and I changed the oil on the weekend cars every year and ran them a few hundred to a couple of thousand miles per year.

Since I'm now retired, don't have to commute, and all the normal businesses I need to visit regularly are walking distance. I'm am down to 500 miles or less on the cars and am letting the oil/filter go two years.

At one year and 500 miles the oil still looks new. All the engines are tight with no significant blowby or oil consumption. They all have well functioning PCV systems, which purge contaminates out of the crankcase before they can condense, and when I do drive them, I always make sure that they are run for at least a half hour to get everything thoroughly warmed up, which will help purge any condensed blowby that gets into the oil during warm-up.

People ask me why I don't drive my cars more often. Notwithstanding hating traffic (Once you don't have to commute it becomes harder to tolerate.) I give them my tongue-in-cheek response.

"Do you know what the worst thing is you can do to an engine"?

"No."

[Answer] "A cold start!"

Duke

Duke,
I am still confused. If all C type oils are acceptable, is there an minimum amount of zddp that they all have? If the minimum level is, say 1100, new, at what level does the oil provide unacceptable wear protection? 600? 400? Do you see why I am asking this: If 400 is the lower limit and you start with 750, driving the car 500 or 1000 miles may never get you to the level of 400, or what ever the lower limit of protection is.

George

[Mike R.]

Re: Amsoil v Mobil1

Oil in a healthy car with electronic fuel injection will last a long time. I know that Ford runs all their cars 12K miles between changes.

I suggest you find a lot of free time and start reading here:

http://www.bobistheoilguy.com/forums...Board=1&page=1

Unfortunately, with most everything else on the internet, you should take most of what you read there with a grain of salt. This NCRS forum is one of the few places where doing this is not so critical (but still a good idea.)

I was very, very concerned with running my OEM (Castrol 5W30 synthetic) oil to 15,000 miles on a new engine in my BMW 335. That is how I found that website. There were tons of horror stories about oil life in the bi-turbo N54 engine to be found there. I run my BMW on a normal day to and from work as hard as some of the weekend warriors on that website do at a racetrack. After 15,360 miles, I had an oil sample sent to Blackstone Labs for analysis by Terry Dyson himself. The end result was that I still had some oil life left and the other numbers were fine.

I now am running Mobil 1 European Formula 0W30 synthetic, but the bottom line of what I think I know from reading that website and my lab analysis is that today's oils are so much better than they used to be, as long as what you use meets whatever specification is required you should be fine. I still have personal perceptions that I have developed over the years and I doubt that these will ever completely go away.

I tried running synthetic oil in my tired old corvette engine for one entire test drive. I had oil leaking from places I never thought about being an external oil path. I switched back to dino oil and all of the leaks went away. The same was true for the transmission except for all of the leak paths were normal. It will be running synthetic oil the next time the engine gets refreshed (after break-in) though.

[Michael W.]

Re: Amsoil v Mobil1

Oil in a healthy car with electronic fuel injection will last a long time. I know that Ford runs all their cars 12K miles between changes.

This is not unusual. My daily beater states 10,000 miles between changes and recommends non-synthetics.

[Duke W.]

Re: Amsoil v Mobil1

Duke,
I am still confused. If all C type oils are acceptable, is there an minimum amount of zddp that they all have? If the minimum level is, say 1100, new, at what level does the oil provide unacceptable wear protection? 600? 400? Do you see why I am asking this: If 400 is the lower limit and you start with 750, driving the car 500 or 1000 miles may never get you to the level of 400, or what ever the lower limit of protection is.

George

I don't know what the minimum P concentration is for CJ-4 (it is 600 ppm for SM), but most CJ-4s will have close to the 1100 maximum. The only way to know is to find a spec sheet for the oil or have a new sample analyzed.

The lowest acceptable amount is dependent on the details of valvetrain design. For sliding surface valve trains, the higher the loading the higher the ZDDP should be, but most OE engines worked fine with as little as 800 ppm P back in the fifties.

The rate of ZDDP consumption is a function of engine health. A high mileage engine that is beginning to wear fast will consume ZDDP faster than a healthy engine in mid-life.

So I don't know what the minimum is for vintage Corvette engines, nor do I think anyone does.

If you really want to be scientific about this you could take oil samples every 1000 miles, have them analysed and plot the P level for as many thousand mile increments as you want. The trend will be down, but only slightly for a healthy engine. That still doesn't tell you what the "minimum" is, so most of us (and the manufacturers) have oil change mileage recommendations based on empirical data going back over 50 years.

Over the years as oil base stock and additive packages improved, manufacturers have generally increased the time and mileage recommendation.

For example, the OE oil change recommendation for my SWC is 6K miles or 60 days and 6K miles or six months for the filter, whichever occurs first, and my newest car ('91 MR2) is 7500 miles or one year for both oil and filter.

The 60 days for the SWC seemed overly conservative, and back in the sixties I changed it every three months with a new filter every other change, so I ran the oil about 3K miles and 6K for the filter.

When the SWC was semi-retired to "weekend car" status in the mid-seventies I extended the oil changes to one year, which was no more than a couple of thousand miles, and by that time P had increased to about 1200 ppm, and base stocks had improved in oxidation resistance over sixties vintage oils.

At the 115K mile teardown the only noticeable engine wear was the cylinder bores and I attribute that to the junky foam oil filter. The Duntov cam was still in spec and could have been reused, the timing chain barely had slack, and the engine interior was spotless with absolutely no sludge buildup.

The engine ran fine (In fact is was always a very strong 327/340 being as how no FI engine ever got the best of it.) and consumed a quart of oil about every 1500-2000 miles, which had been pretty consistent since post break-in. I refreshed it primarily because I was worried about the connecting rods, not because it was worn out, and I also wanted to massage the heads and do a general "blueprint" job to maximize performance and reliability.

The the above data is how I came up with my collector car oil/filter change recommendation of one year or 5K miles, and it should be done at the beginning of winter storage since fresh oil in the crankcase does not begin to "age" (consumption of additives and oxidation of the base stock oils) until the car is put back in to service the following spring.

Most guys change oil/filter more often than really necessary, but forget about other fluids like anti-freeze and brake fluid and the transmission and axle oils.

If your engine is relatively fresh and was properly redone, has an OE design cam/valve springs, use modern C-category oil, follow the above oil change recommendations for collector cars that run a few hundred to a few thousand miles per year, and use a modern cellulose air filter, you'll be dead before the engine wears out

An orignal low mileage Flint-built engine in good health or a properly restored example will probably never have a problem running SM oil, but for the same price you can run CJ-4, which has a better additive package for vintage engines.

If you could buy a pound of potatos from store A for a buck and store B was the same price, but threw in a free pound of green beans with the pound of potatos, which would you choose?

Duke

[George J.]

Re: Amsoil v Mobil1

Duke,
thanks. Your opinions coincide with what I have suspected. I think people are worrying too much about this. I would go further and say that I don't think any of the brand name oils would cause a failure or premature wear if used for less than 3000 miles in our cars, whatever their level of zddp is.

George

[Clem Z.]

Re: Amsoil v Mobil1

here it is for what it is worth from GM techlink

[Stephen B.]

Re: Amsoil v Mobil1

Dick
As stated earlier I don't know the price of Comp Cam Oil or their Zink additive ,but I will find out next week and post it.My understanding when I last talked with them was that the addative was compatable with any oil. If that is the case that would give you the most flexibility at an affordable cost.
Stephen Barrett (21558)

I just got off the phone with Compcams tech people,and as promised I am forwarding info on this site.Blended high zink oil (2000 parts per mil.)$5.50 per quart. 12oz.additive, treats 5 to 8 quarts $11.00.Sounds like to me this is a very practical and affordable addition to all the other hi zink products out there.Theres no excuse for loosing a motor for lack of zink any longer.
Stephen Barrett (21558)

[Duke W.]

Re: Amsoil v Mobil1

2000 ppm... P? Zn? Do these clowns at Comp Cams know what they're talkilng about?

Do you?

For God's sake you don't need 2000 ppm P for a vintage engine. The 1100 ppm in CJ-4 is more than adequate and more than was contained in most engine oils when our cars were new.

In the long term over 1400 P has shown to cause an exotic corrosion mechanism.

The BS just never stops!

Five-fifty a quart! Total ripoff for something that is absolutely not necessary.

I expect better from someone who's been a NCRS member longer than me.

Duke

[Dick W.]

Re: Amsoil v Mobil1

$5.50 a quart, hmmm, that equals $22.00 a gallon. You can buy Rotella for a little less than $10.00 a gallon / 4 = $2.50 a quart. I have enough Scotch Irish in my blood to buy the best for the cheapest price.

[Stephen B.]

Re: Amsoil v Mobil1

Duke
Once you get by the sarcastic know it all attitde your probable a pretty smart guy. It's a shame there's only one way to do anything when your on this forum.I simply passed on what was represented to me by the compcam tech people so others would have choices. By the way a quart of Mobil 1 costs about $5.50 at Autozone last time I checked.Have a nice day Duke.
Stehen Barrett (21558)

[Duke W.]

Re: Amsoil v Mobil1

$5.50 a quart, hmmm, that equals $22.00 a gallon. You can buy Rotella for a little less than $10.00 a gallon / 4 = $2.50 a quart. I have enough Scotch Irish in my blood to buy the best for the cheapest price.

Walmart's SuperTech house brand CJ-4 is about $8.50 a gallon. Take it from a Welsh-Saxon... maybe that's why I'm so feisty and combative...

Duke