Everybody aware of ZDDP and classic cars?

Dear fans of the venerable long-roof,

I just did a search of this forum and some folks are clearly aware of the potential dangers of running a "mature" engine on the current formulations of motor oil, but just in case not everyone has heard I thought I would remind everyone.

Until very recently, most U.S. manufactured cars had was was called a flat tippet camshaft. This means that the push-rods are simply moved by sliding along the surface of the camshaft. To improve efficiency, a new kind of camshaft was invented called a "roller camshaft." These sorts of camshaft incorporate a roller bearing so that the push rods roll rather than slide over the surface of the lobes. If this is all new to you have a quick look at this Wikipedia article:

http://en.wikipedia.org/wiki/Camshaft

With the use of roller camshafts, oils could be reformulated since there was not as much friction. In 2004, this was done on the premise to reduce pollution. The key ingredient that was reduced is Zinc dithiophosphate which is commonly abbreviated as ZDDP.

Shortly after that people started to notice mysterious camshaft failures. The first group to notice this was the owners of classic British (and related) sport cars. The high-rev little engines of MGs and similar cars started to have camshaft failures as little as 2 years after the oil formulation was changed. It has taken longer for cars with larger engines to "feel the pain." The 300 cid V-8 in my 1965 Buick Special was rebuilt in 2001. There were valve timing irregularities found in 2011. The engine had less than 50,000 miles on it at the time. A friend of mine had to replace the camshaft in a 1970 El Camino. Inspecting the camshaft showed signs of excessive wear. If you haven't heard about this, you might want to read this article from Hot-Rod magazine:

http://www.hotrod.com/techarticles/engine/flat_tappet_cam_tech/viewall.html

A bit of web searching with the keyword "ZDDP" will give you probably much more information than you can swallow!

Since the problem was ZDDP deprivation was discovered there has been something of a panic to deal with the problem. The most common solution was using a ZDDP additiive. However, with time, this has also called into question. The preferred solution today is to purchase oil specifically formulated for a classic car engine.

On the V-8 Buick forum that I also frequent there was a thread which some of you might find interesting. It was started by Jim Weise who is the engine builder who created my assertive 509 horsepower big-block engine for my trusty wagon:

http://www.v8buick.com/showthread.php?222499-New-Oil-tech

That first posting explains the problems of modern oils that have too high a detergent content that effectively undermines the benefit of adding ZDDP additives.

Needless to say choose your oil for your classic wagon carefully!! I plan to stick with what Jim Wiese has recommended for my engine.

Hope this has been interesting for everyone.

Cheers, Edouard

 

According to Isky Cams and others we deal with there are three recommended flat tappet approved oils on the market Brad Penn Racing oil, Pennzoil GTP Racing Oil and Valvoline VR1 "non street legal" racing oil (not to be confused with what you normally find on the shelf it usually has to be special ordered and must say "off road use only"). The alternative to this would be to run a break in additive or a product called ZDDPlus that can now be found pretty much everywhere you buy auto parts. I prefer using the Pennzoil 25W-50 oil in our flat tappet dirt cars and I prefer using the Comp Cams camshaft break in lube part #159. You will also find that most of your favorite cam companies are starting to bottle their own oil blends just for this purpose as well. Running off the shelf motor oils in flat tappet camshaft engines has now become a risky business I recommend at least an additive. BTW Lucas Oil Stabilizer seems to do a great job too when used as recommended.

~Couch

 

Speaking of Lucas, they also make a Zinc additive designed specifically for engine break-in...available here at Napa, retails for about $12.00. My Napa plug for the day...which in my eyes justifies my being on the forum all day long.

 

I'm heading right over to my friendly neighborhood Napa for some oil additive.
I actually do have to go there to get a new tractor battery today, might as well get some oil filters and a can of Napa Know How while I'm at it.

 

OK, I'll admit that sometimes i'm a bit out of the loop but how on earth do they justify motor oil as being illegal for street use (I know, statists don't have to justify themselves but geepers!).

mike

 

Think it is an issue of which cars can use which oil.

Hi Mike and fans of da' long-roof . . . . . .

As far as I know, there is no such thing as oil that isn't "street-legal." However, you are obliged to meet the pollution standard for your car when manufactured. If you use an oil with a high ZDDP content, you'll poison your catalytic converter and have to replace it to pass your smog test. At least that's my understand of the situation. Am I wrong on this?

Cheers, Edouard

 

We have bottles of Valvoline that say "not street legal" on the label and for "racing only" as well. My first thought seeing it was "how on earth could you ever prove that?"...."why are you in court today Mr. Johnson?"

 

That is true Edouard, the box says not recommended for vehicles with a catalyst.

 

That Dewey!

Some folks say the Shell Rotella line of oils are good for flat tappy engines, none of them have a "S" gas engine rating anymore though. Anyone have an opinion on the Rotella oils?

 

Rotella is great oil, their 15W40 Diesel is probably one of my fleet accounts favorites. The Chevron Delo brand is also popular. Just sold a 55 gallon drum of Rotella 15W40 to a construction company...for a mere $795.00.

 

Interesting discussion. I am wondering, though, if Canadian oils are different from the American. My brother's flat tappet engines have all exceeded 500,000 miles with no cam issues, and that includes the Chev 305 in his 86 Parisienne Safari, an engine that was known for cam issues. I know of one Ford 302 with almost 1,000,000 miles on it, with the original cam still in place, and not a spot of trouble. Wonder if it makes a difference that these engines all run Castrol Syntech 5W50 full synthetic.

 

Good question!

Hi Michael and fans of "mature" vehicles,

Unfortunately, I don't know the answer to your question. Castrol has a separate website for Canada - so that is suggestive the oils sold in Canada are different. However, does Canada require the same sort of catalytic converters as the United States?

The change in the United States formulations came in 2004. So it doesn't mean all catalytic converters cannot handle ZDDP. Catalytic converters date from the 1970s. It might also be the case that the levels of ZDDP in oils before 2004 were okay for older engines at least when not put under a lot of stress. However, maybe the US regulations went too far and vehicles like my trusty wagon have paid the price.

Does anybody have some additional information on this question?

Cheers, Edouard

 

The problem with using "C" oils in common street engines is the amount of detergents they have in them. They are formulated to handle nasty commercial engines and tons and tons of mileage. The reason you don't really want to use a "C" oil in a typical automotive engine is some of the solvents meant to break down heavy sludge and carbon can also eat up bearing overlay given enough time. The common mistake is thinking that C oils are just for diesels but it's actually for anything considered "commercial use" so HD gasoline engines benefit also.

~Couch

 

Unfortunately this is what the tree huggers want you to think but in fact the German auto manufactures proved this wrong and require you to buy your oil from the dealer because it comes with the right amount of ZDDP or they will void your warranty. This is more likely another corporate America scandal where someone got paid to say this in order to be able to produce a cheaper product and sell it for the same price. Remember R12?

~Couch

 

The long and short of it: The only cams that seem to be greatly affected are the cams with real aggressive lobes. Cams and lifters have to "learn" how to get along with one another the most crucial time in an engines life is in the first couple of percent of time it runs. If you can get past the first I'd say 2,000-3.000 miles with little or no "unusual" wear then I'd say the motor will go the duration so long as it has some kind of oil in it. They didn't start drastically reducing the ZDDP levels in oil until ~04-05-06 with the new SM standard I think however most racing oils meet SG or SH standards. From then it seamed like every engine you would start with flat tappet cams that had any real aggression at all would get eaten up in the first half hour. We were warranting cams left and right and finally started to realize what was happening. Now I won't build a flat tappet engine unless the rules in the class they want to race dictates that they must have flat tappet cams and then I am very cautious how the cam is broken in and how it's oiled. Cutting groves in the lifter bores to get oil sprayed right on the cam lobe helps and using "non street legal" oils help too. If you look at the bottle and it says "API service SM or SN" then it's the same trash we have down here in the good ol USA. However I have sold some truck engines with mild cams for strong torque and they seemed to do just fine on SM-N oil. They were all work trucks so I had to find a way to compete with crate engines and flat tappet cams were my only option they both run great and now have well over 100,000 miles on them with no sign of failure on the horizon. Again I used very very mild cams and possibly the most important thing as far as hardware I used the hardened pad GM lifters instead of the ones from the cam companies. The lifters you use are part 2 to this whole mess. There are really only 3 companies in the world that produce lifters GM (Delco or Delphi), Eaton, and Johnsons. Johnsons was bought a few years ago by Topline so they pretty much eat up all the import stuff. Eaton is what you commonly find in cam kits and my personal opinion is I'd rather make my own lifters than use theirs then for us GM guys Delco or Delphi have the same lifter in a different box and they are awesome. The last ditch option you have is to get lifters with PDM oil holes in the bottom to get pressurized oil between the cam and the lifter this would be the definitive solution to the problem and it's how the factory would have fixed it if everyone hadn't adopted roller lifters instead.

So to answer your question is there a doughnut on the oil bottles that say API service SM or SN? If so you have the same trash we do but what made the difference? The cams your brothers car had already broken in on the old oil limiting or possibly eliminating the need for SL or before oils that and the cams may not have real aggressive ramps and valve ascending rates on the lobes. As the cam companies will tell you cams wear out from the top down not bottom up so spring pressure and max lift have a LOT to do with how long a flat tappet cam will live. Break in procedure can mean everything to the real aggressive flat tappet cams but that's a new thread all together.

~Couch