About 2 months ago I started hearing bits and pieces about how our oil, here in the United states has been slowly and very quietly been reduced in it’s ability to lubricate engines like our Rovers and all the older V-8’s.

Turns out that somewhere back in the 40’s there was an additive, ZDDP, put in all engine oils that would help lubricate our cams and lifters since they really don’t have a direct oil flow to keep them well lubricated like all the newer over head cam engines. Then back in 1996 this additive was cut from 800 parts per million to 400 parts per million, which can be verified by the API emblem on each bottle of oil. There has been a recent change again where the oil has been dropped from 400 parts per million, with a SL rating on the bottle, to a new SM rating at 200 parts per million.

From what I have found so far is Castro’s full synthetic still has the SL rating and although made in Germany, it is stamped for resale in the United states only, Quote, “ Not for sale outside the United States”. Amsoil 10/w40 still has the SL rating also.

In talking with a friend who has spent some time researching this, there are only a couple oils still available in the United States and they are in the $10 to $13 range, Red Line racing oil, Royal Purple racing oil, Harley Davidson motor cycle oil and Mobil 1’s oil for Harley’s. These are only still because they are not required to follow the mandated API standards for stock type motor oils.

Turns out there is only one old additive, sold by General Motors called EOS, that actually contains ZDDP.

So for those of use that are always asking what is the best brand or best weight of oil, you now need to look at what is still left in the oil bottles that will maintain our engines, ZDDP. Rover engines are know for internal engine noises and wear on the cam and lifters, I am not saying this is the reason why, but I am saying this may be part of our wear problems.

So the next time you go to your favorite auto parts store check it out, find a bottle of oil that is not marked SM.

Just some food for thought.

Mike

 

Sorry to dig up an old thread but I too have heard the above. From what I understand two very important specs for oil for our rovers are shear and zinc content. My question is does anyone know these specs for the Royal Purple xxW-40 oils? I am thinking of changing from Mo1 to the RP and have been unable to find the info. I'm sure OKDisco will know.

FYI Mo1 0w-40:
Shear 3.7 (@150c)
ZDDP 1000ppm

 

No, but if you find out anything, let me know.
Thanks

 

OK,

So I just called Royal Purple and asked about the ZDDP and Shear on their 10&15W40 Oils. Their tech could not give me a specific answer. For ZDDP they said the max allowable to be API registered but didn't know what that number was and they couldn't give me a number on shear but said "I guarantee it's the highest in the industry." The guy I spoke to was asking someone else and those are the only answers I could get, no one knew the actual numbers. They seemed nice enough but I need more than that. Anyway, I think at this point I'd have to see the actual numbers in writing before I believed anything.

Everyone says the RP is good stuff but if they themselves don't know, or won't give those factors I'm going to stick with the Mo1. I really wanted to give it a go but I just don't trust unquantifiable statements like "Most" and "Highest."

Sorry, I tried!

-T-

 

Found this:

http://board.moparts.org/ubbthreads/...2&Main=3966354

Lists Phos, Zinc and other info about tons of oils, no shear though. Thought it was interesting.

 

Actually Mike, your facts are not spot on.

ZDDP (zinc dialkyldithiophosphate) has been used as the primary anti-wear agent for motor oils for more 70 years. It is cheap and very effective. Traditionally, the levels in motor oils was 1500+ parts per million, not 800 as you suggest. As roller rocker engines replaced flat tappet engines, the need for anti-wear agents declined. I believe the old Rover V8 was one of the last flat tappet engines on the road.

The US EPA legislated a longer life for cats in the mid-90s culminating in a due date in 2007. Though ZDDP is not a polutant itself, it can shorten cat life over a long period (from 10 to 8 years in some cases), so as a consequence, the pressure of the EPA on US car manufacturers lead the car manufacturers to pressure the motor oil makers. ZDDP levels have been reduced enormously in the last few years, without much of an advisory to the tiny flat tappet public.

A few years ago, a disgruntled British car specialist garage ran into a bad low zddp experience or two and wrote Oil Is Killing Our Engines (it is everywhere now on a google search. here is one posting http://www.memphisbritishcars.org/ne.../oil200702.htm )
It is alarmist in tone and it caused more damage that benefit. However, testing has supported much of its findings. (Please do not rely on the recommended oils in the article. They have changed.)

Many people ran to GM's EOS as you note..but GM took it off the market in the US in 2005. It was still sold outside the US by GM and we had shipped in from Canada at one point. Recently, the outcry has forced GM to return EOS to the US with silly warnings to avoid EPA wrath. EOS is simply motor oil with a high zddp concentration. However, if an additive is wanted, zddplus (google it) is cheaper and more to the point. If you require quantity, we have found it can be bought by the barrel much cheaper from other sources.

Flat tappet and even other racers use high levels of zddp as a matter of course. For the public,the motor oil constituents keep changing and are designed for engines that do not have needs of a flat tapper. The right additive seems cheap insurance for the remaining flat tappet population. At the moment, Moble 1 15W50 and some others have a sufficently high level of zddp on their own (1200 ppm) to satisfy everything a flat tappet engine can want post break in (1000 miles after new engine, tappets or cam). For the break in period, flat tappet cam makers recommend the use of their own extremely high concentration of zddp as a condition of sale and warranty.

James

 

I don't believe Mike was stating that historically ZDDP levels were 800ppm. The point was to point out changes in recent years to the API standards ie SM/SJ/SL etc and the progression of declining ZDDP content to levels most would consider dangerously low for our mid cam flat tappet V8s. While 800 is not as high as conventional wisdom would say is ideal, I think most would agree 800 is sufficient (albeit barely) to protect our engines. I, personally, would like to see a min of somewhere between 1K and 1200 but not at the expense of other important factors.

Please don't take this the wrong way but I really don't see how the post either rebuffs the OPs statements, offers any evidence to the contrary or adds anything constructive regarding oil decisions for our rovers.

I emailed API yesterday to get correct info as to general specification requirements and min/max allowable ZDDP levels for currently available classifications of API certified oils. haven't heard back yet but will post the info when I get it.

 

Ouch, not nice, but thank you for your critique. You are right about my posting if you don't read it or have pre-decided not to believe it.

I did not hope to prove anything to anyone..only help. What I indicated was the results of OUR research and that there are choices for each owner to make. 1. You can take a chance and use any oil, 2. you can rely on what oil companies tell you assuming they tell you anything meaningful and then follow that without testing, 3. you can add enough zddp to bring you up to the traditional levels.

The only thing we can be sure of is that the last choice can cause no harm (70 year track record) and possibly (who knows) avoid damage. We have no long term track record on any other option

I sincerely hope everything works out long term for you and others at the lower zddp levels. Let's give it few years and if your option group is still running fine withiout cam or lifter damage, my team can save 2 dollars an oil change.

James

 

interesting reading...it'd be hard to really tell "what is best" without an A/B/C experiment. Most of us have vehicles with untold thousands of miles on the motors. Some of us do not know the history of the vehicle and whether it was well cared for or not.

I could spend big-bucks on Royal Purple oil and experience a pre-mature failure. The cause of the failure might be traced back to poor maintenance by previous owners, but instead I'd immediately assume that Royal Purple was the culprit.

...hopefully that made sense.

I think everyone wants what is best for their vehicles but with all the information and misinformation in the world, it's very difficult to determine. Now if anyone has a few fresh motors that we can do a side-by-side comparison on...let's make it happen!

 

Just catching up to this thread, and I found Bartell's post very helpful--didn't see it as contradicting Mike's but expanding upon it. Should I take from this discussion that Mobile 1 15W50 is the best easily available option for a Disco at this point and should satisfy the needs of the engine? Or am I not following this closely enough?