API 'backwards compatability' a big lie???

[addyguy]

Oil companies and the API always state that API specification levels are 'backwards compatable' - an oil that is certified SN wil work in all previous certification levels.

We know that the API has lowered the amount of Zinc and Phosphorus anti-wear additives in newer oils. Oil compnies and the API claim that newer anti-wear additives make up for the reduced Zn/Ph in newer oils.

So, if that is the case, WHY do some oil companies, many professional engine builders, and others push for, and assert, that older engines need high-Zn/Ph oils? The market for 'high zinc' oils keeps growing all the time, and there has been no real effort by the API to stop it, or get help stopping it.

If the API REALLY beleivs that lower-Zn/Ph oils will not harm older/high performance engines, why is there not more of an effort to make people see this?

OR...is the backwards compatability one big lie, and actually lower-Zn/Ph oils do NOT protectcertain engines, and all these builders and oil formulators are right, and there is a need for this oil?

Does the API TRULY believe what it is saying???

 

[Hokiefyd]

Originally Posted By: addyguy
The market for 'high zinc' oils keeps growing all the time, and there has been no real effort by the API to stop it, or get help stopping it.


I don't see the need for the API to "stop the movement". The API is in the business of "current oil" standards definition, right? That current level is SN. If somebody wants to blend an oil that has doesn't meet SN, it won't have SN on the bottle. It's up to the consumer to look for it, and I'm not sure API has any place trying to "regulate" that kind of stuff. There are a number of oils out there that don't seem to have any type of API certification/approval/etc.

Quaker State High Mileage was a notable example, and from what I recall, their new Defy may be another. The oil does not meet the specifications of SN and it doesn't have SN on the bottle.

 

[Rand]

I would use API SN in a regular car calling for API SJ

thats over 10 years.


now if you are talking about compatible with some 30 year engine that recommended api SF and was rebuilt with stronger springs and an aggressive cam... well I would just use that uncommon "common sense" thing.

 

[tig1]

"Backward Compatibility" to SM and SL only is what my SN M1 5-30 bottle says.

 

[artificialist]

Many engine builders use flat lifter cams that are larger than OEM flat lifter cams, that is why they don't want you to use API SM or SN oil. Aggressive cams increase pressure on lifters to a point that OEM cams don't.

The Jeep 4.0L and 4.2L engine is extremely common, and yet it almost never experiences cam and lifter problems while using ordinary SM or SN oil.

 

[addyguy]

Yes, you're right, that API is in the business of developing 'current' oi standards, and that is what they should concentrate on.

BUT, one thing they do say repeatledly s that their newer standards are backwards compatible. So new SN oils should work perfectly fine in ANY engine.

I'm just suprised they don't 'make more of an effort' to 'discredit' companies or builders that claim that newer oils won't protect old equipment, and you need their 'high-zinc super blend'...I'm just suprised the API doesn't go on the offensive against these claims more.

 

[HerrStig]

This is an ad nausem topic in the BMW bike forums, with strongly held opinions on all sides. Many people hold on to their older bikes, and the whole zinc thing is always popping up. I have a 1982 BMW airhead, back compatability is of some interest. Should I use T6 in it... yes, no, maybe....

 

[Hokiefyd]

I think API says that any definition earlier than SJ is obsolete...and many of these engines are much older than SJ. For example, from their website:

"For automotive gasoline engines, the latest engine oil service category includes the performance properties of each earlier category. If an automotive owner's manual calls for an API SJ or SL oil, an API SM oil will provide full protection."

The first sentence taken out of context implies that you can run SM (or SN) in anything. But the second sentence seems to clarify the first, and that full protection is provided for engines requiring SJ or later.

The way I read that, anything older than SJ is an "obsolete" definition and API oils and service definitions do not apply.

 

[Hokiefyd]

API brochure on engine oil

This also says: "(FOLLOW YOUR VEHICLE MANUFACTURER’S RECOMMENDATIONS ON OIL PERFORMANCE LEVEL)"

They do seem to leave it somewhat open-ended, and up to the vehicle owner.

 

[friendly_jacek]

I don't think there is a problem if one pays attention to proper viscosity. The old heavy duty engines most likely specified 40 weight oils and those are excluded from the P limits in current API certification.

Now, if one is using current low viscosity, energy conserving oils in those old engines, there could be trouble.

Also, one wants to research the P values in the current 40 weight oils before using them in special applications that require extra anti-wear protection.

 

[NovaMan]

I don't think the API cares about old engines. Why should they? There aren't really a whole lot of them on the road, and most of them are already well broken in and won't suffer from the new low-Zn, low-P oils (like Jeep 4.0/4.2L engines). It's mostly the people rebuilding old engines or hot rodding them, and hot rodding is always done at your own risk. And who's going to sue over a $120 cam and lifter set? Even if they do AND they win, it's only $120.

 

[addyguy]

Interesting.....I hadn't thought that the backwards-compatability edict was intended to only apply to 'curent' API specs (ie. API SJ and newer oils).

That makes a lot of sense - thanks!

 

[NHGUY]

I wouldnt want to use SN in an engine rated for SA (non detergent)...with no filter to catch the crud,there will be large deposits plugging up everything.This is the only exception to the rule I could see.

 

[Artem]

Yea the older engines require thicker oils so the API seal doesn't apply. The owner would have to use an appropriate oil in that case.

 

[lexus114]

Originally Posted By: Artem
Yea the older engines require thicker oils so the API seal doesn't apply. The owner would have to use an appropriate oil in that case.




Do they? Tig1 was using MB-1 5W-20 34 years ago.

 

[1345]

It's a big lie. Car companys do not want vehicles to last more than 10 years it's bad for thetr buisness and they tell the API what to do. You can not even change trannsmision fluid in new cars any more. Soon you will not be able to change the oil in new cars they will call it life tine oil.

 

[A_Harman]

Originally Posted By: lexus114
Originally Posted By: Artem
Yea the older engines require thicker oils so the API seal doesn't apply. The owner would have to use an appropriate oil in that case.




Do they? Tig1 was using MB-1 5W-20 34 years ago.


That's true. 20-weight oils existed long before anyone heard of CAFE standards. The owner's manual for my GMC truck V6 specifies 20-weight oil for the 305 up to 90F ambient temperature, and does not go above 30-weight all the way to 120F for all engines in the series.

 

[exranger06]

Originally Posted By: Artem
Yea the older engines require thicker oils so the API seal doesn't apply. The owner would have to use an appropriate oil in that case.

Just about every 40 weight and 50 weight oil I've ever seen is API rated. If by "API seal" you mean the energy conserving starburst on the front of the bottle, then you are correct. Only 30 weight and lighter oils are ILSAC rated as energy conserving. But that doesn't mean they're not API licensed.

 

[Solarent]

I think it is also important to note that the API's primary role is to provide a standard that meets the performance requirements of many engine types, and now not only engines but also emissions equipment and other resources used on vehicles.(Hence, Resource Conserving oils)

As the specifications have evolved, the performance requirements of the oil have also evolved; with newer oils providing greater protection in any of the Sequence Engine tests used in previous service categories. For example When Sequence VI D came out for measuring the improvement of fuel economy it replaced previous fuel economy tests due to more accuracy in testing data. The same is true with other performance tests.

As these tests are developed, they are adapted to newer engine technologies, and thus the oils are also adapted to meet the new requirements. In the case of older engines that require high zinc content, the lubricity can be made up with other additives, however, zddp is the most common and therefore most sought after in the consumer market.

New specifications are arguably best suited for newer engines, but IMO specific applications and maintenance history on a given engine trumps generalized specifications every time. What may work for one customer in Florida may not work for another customer in Canada, depending on engine conditions. This is why if you are serious about providing your specific engine with the "best possible" protection your only option is to run an oil monitoring system make selections that give you the best possible results.

Oil manufacturers recognize this need and this is why there are so many different products even under the same brand. Viscosity requirements, additive requirements, all these must be considered when matching an oil to your engine. There is plenty of evidence on this site that some engines prefer certain types of oils/additive formulations.

The API does their best, and I don't think we can fault them for focusing more on newer engines and newer lubricants. But we can still mourn the sacrifice of oil performance for better emission controls. I know I will.

 

[Coprolite]

A new oil that is blended today to meet a previous standard, say SL, would most likely be better than an SL from "back in the day"....

A highly modified engine has never really been serve by any API spec. I would feel comfortable using an SN oil in pretty much any stock application.