Flat Tappet Motor Oil, Public Service Announcement ZDDP

[jamesroney]

Regardless of what you know, or think you know, or wish you knew...there is a change coming for motor oil.

I am not here to debate the merits of using flat tappet motor oil for flat tappet cams. That ship has sailed. But if you own a flat tappet Ford V8, Or a Cummins 6BT...be advised.

Current API CK-4 spec oil is shipping with the full ZDDP protection package for flat tappet Cummins in 15W-40 weight. Everybody thinks that Rotella, or Delo, or whatever has the right ZDDP package, but since 2020, it has ONLY been in 15W-40 weight.

As of January, 2027...the American Petroleum Industry, in collaboration with the Environmental Protection Agency and Major OEM engine manufacturers HAS AGREED to unleash API CL-4 to the market. This means that ZERO mainstream diesel motor oil will have the "requisite" protection for your flat tappet cam.

I am perfectly aware that Ford, Cummins, GM, Daimler, have all agreed to the change. I am also aware that ZERO testing has been performed by any manufacturer using degraded, contaminated, used, dirty, motor oil. (and yes, I am aware of the accelerated soot protocol)

So, if you want decent motor oil for your Bronco that meets the old spec in YOUR owners manual for SD or SE motior oil...this is your last chance is to buy some Rotella or Delo in 15W-40 with the CK-4 spec on the back of the bottle. Yes, you have to turn it around and read it. Yes, it has to say CK-4 in the little circle. Yes, that CK-4 gives you added protection that you can not buy in lighter weight oil.

It will take a few months for inventory to deplete, and since all of the OEM's say it is fully backward compatible, there will be both types on the shelf at the same time for a while.

If you want my opinion on why or if you want ZDDP in your Bronco, just tag me below. (or your Cummins.)

Or just google: "comp cams ZDDP catastrophy"

This is not applicable to any Explorer 5.0 or Mustang 5.0 roller cam engines.

 

[toddz69]

Had to look up the 7.3 Powerstroke to see if it was flat tappet or roller. Looks like it's a roller!

Todd Z.

 

[okie4570]

Had to look up the 7.3 Powerstroke to see if it was flat tappet or roller. Looks like it's a roller!

Todd Z.

The 6.9l IDI is roller also, I had to look that one up, I couldn't remember. Almost nobody around still owns one anymore though also lol.

 

[dmoses42]

If you want my opinion on why or if you want ZDDP in your Bronco, just tag me below.

So, when all the CK runs out and all we are left with is the CL, is the ZDDP additive a suitable work around? I'm curious because I have my 302 in my Bronco, but I also have a '68 Ford F100 with a 390, and a '72 Nova that currently has the original very tired 307 which I will likely upgrade to either a 4 bolt 350 or a 402. No desire to go the LS route. I've read about the current engine oil zinc deficiency on BITOG, and with all my old motors, I don't want to destroy them with the lubricant used within...

 

[jamesroney]

The 6.9l IDI is roller also, I had to look that one up, I couldn't remember. Almost nobody around still owns one anymore though also lol.

Yup, lots of those 6.9’s and 7.3 still running around. Nice roller lifters.

The AMC 258 and later 4.0 ran flat tappets thru 2006. But nobody ever got any horsepower out of those.

 

[jamesroney]

So, when all the CK runs out and all we are left with is the CL, is the ZDDP additive a suitable work around? I'm curious because I have my 302 in my Bronco, but I also have a '68 Ford F100 with a 390, and a '72 Nova that currently has the original very tired 307 which I will likely upgrade to either a 4 bolt 350 or a 402. No desire to go the LS route. I've read about the current engine oil zinc deficiency on BITOG, and with all my old motors, I don't want to destroy them with the lubricant used within...

The short answer is the expensive one. The old spec SD/SE will still be blended for the racing guys. It was just nice to get a quart of Rotella T4 for $3.75.

You can always create your own chemistry set and blend your own, but as with all chemistry, too little is bad, and too much is also bad. Gotta hit the sweeet spot with the whole additive package. But definitely do-able.

Good news is that your catalytic converter will last much longer. Even if you don’t have one…

 

[Broncobowsher]

I recall even the 70s GM 5.7 diesel got roller lifters. Based on an engine with flat tappet. My understanding was the naturally aspirated diesels needed all the help breathing they could get. The roller lifter allowed quicker valve opening and closing so you could get as much breathing as possible. You can't run more duration as you need the valve closed early enough to build the cylinder pressure for diesels to do diesel things. So quick opening and hold as much as possible was needed, and the roller lifter was used.

I've owned several engines that are bucket on valve. No roller. Just a cam lobe pushing on what looks like a flat tappet, but delete the hydraulic stuff, pushrods, rocker arms, and the lifter pushes straight on the valve. Motorcycles, cars, trucks.

I'm going to build a vintage small block ford boat engine in a couple years. Debating the cam. I'm all over the map on this one. I started by wanting to do a repop of the solid lifter k-code cam. I just think the solid lifters and the sewing machine sound of the lifter tapping away sounds so good. But I want a little nicer idle. Don't want it sounding like a race car at idle. The hydraulic flat tappet is looking tempting, the original 5.0 HO motor from '82 was nothing more than an existing marine cam but put into mustangs. That has me looking at retrofit hydraulic roller cams. Anything from a stock HO or Explorer cam. Also looking at getting one custom ground. Which has me back at could I get a tiny solid roller cam custom ground. So I could have the k-code sewing machine solid lifter sound that you only get with solid lifters and set valve lash. Be a bit of a waste of a high end solid lifter setup for little more than a stock cam. But I recall that solid rollers don't like extended idle, except for one lifter that takes it well, and I have no idea what that one is. Good thing I am not in a hurry to build this.

 

[pbwcr]

I new it was coming and by searching I found there are many oil choices that have even greater wear protection than the ones with ZDDP.
Many of the choices with superior wear protection are European certified (ACEA). However there are still good choices with good USA oils. Turns out there good oils are more costly.. One of my rigs use 5w30 and the choices I found are as follows:
Mobile1 GP4, Amsoil Signature GP4+Gp5, Liquid Moly ACEA GP4-5, Royal Purple HPS w Synerlic GP4
Prices range from $9 to $ 12 per quart
Do your own viscosity search and look for GP4 certification or higher for your oil choices.

 

[661buster1963]

So the rotella 15-40 with ck-4 is something I should stock up on for my 351w flat tapper engine? Excuse my ignorance but this in not a break in oil for but to be used after break in??

 

[pbwcr]

Yes high ZDDP. Great for a diesel motor, not so great for a 351 gas motor.
Better was is to use 10w30 and add your own ZDDP. That is what a lot of us did before better oil options became available.

 

[jamesroney]

OK, small rant coming...

So funny thing about that "break in" oil.

There really is no such thing. "Break-In oil" is marketing hype for "You did a shitty job building your engine, and you have a crappy design...so we want to flush out contamination as soon as we can." There are large groups of people who benefit financially by peddling break in oil. And we can talk about that. But here's something to consider.

Within my lifetime, and starting from my earliest recollection, there have been New car sales, and fleet/rental car sales. So I can definitively talk about cars from 1968 and up from experience, and reasonable back to the 50's based on published literature. But let's just start from 1966 so I don't get accused of using AI.

For you neophytes: the following is HYPERBOLE. It is general language used to convey a meaningful truth. Nothing in this world is absolute, and there are always exceptions. But the absence of disclaimers and specifics does NOT nullify the basic truth. Unlike Fake News, or misinformation...where the absence of specifics is intended to convey the opposite of truth. Hyperbole is convenient language so I don't have to type thousands of pages of disclaimers.

If you bought a brand new Bronco in 1968, your Ford owner's manual would tell you to change the oil at 6,000 miles. (under normal service conditions) It has a flat tappet camshaft, and plain bearings, with a carburetor, and rudimentary ignition control. In 1966, Ford was making a brand new engine in a brand new vehicle every 9 seconds. Day and Night, 24/7, for 365 days. The engine division TakT time was ~1.9 seconds. So for every available hour that the plant was scheduled to be running, (minus holidays, plant shutdown, and changeover) An engine needed to leave the "factory" every 1.9 seconds. But go ahead and use the consumption rate... 31 million seconds divided by 3.2 million vehicles = Every 9.7 seconds a brand new car "appeared."

Of the 3.2 Million vehicles that Ford Sold in 1966, NONE were required to do anything "special" in the first oil change interval. You go to the dealer, or to Hertz, you get in the car, and you drive it 6,000 miles. Then you change the oil. From 1999 to 2013, if you bought a BMW 3 series (E46 or E90) or a Fiat off the lot, you were instructed by the manufacturer to change the oil based on the service light, which would come on between 15,000 and 18,600 miles.

The notion of "break in" oil is real, and valuable, but ONLY if you are solving a problem that someone CREATED. High performance engines, flat tappet engines with radical cam profiles, Engines rebuilt in an outhouse, Engines with questionable metallurgy, Engines with questionable tolerances, and engines subject to harsh conditions do indeed benefit from a "flush."

But let's talk a little bit about oil. Base Oil does not wear out, and does not get old. You can crawl under an old 1960's Ford 9 inch in a wrecking yard, and drain the gear oil, and it will look brand new, smell new, and perform just like it did 60 years ago. Most people on this forum have seen this. Oil gets dirty, oil gets contaminated, and the additives in the oil DO wear out and get old. But the base oil itself can be filtered, cleaned, refreshed, and restored. So what is the purpose of the oil? Lubrication, Heat transfer, metal treatment delivery and detergent. In a perfect world, your motor oil would deliver all of the good stuff to your engine, and drop off all of the bad stuff in the filter. After a calculated service interval based on exposure, the oil would be drained, cleaned, analyzed, and re-constituted. The depleted additives would be restored, and the oil would be re-used. A new filter would be installed. The oil can easily outlast the life of the car, the engine, and the owner. But very few people do this, and only a few select fleets do it...because new oil is cheaper than renewing old oil.

The benefit of using Rotella CK-4 15w-40 in your flat tappet Bronco is to get that additive package for CHEAP. At todays prices, you should be paying $3.75 per quart. (and I will call it ZDDP, but it is really a combination of a bunch of things but yes, ZDDP at the "right" concentration. ) API service index CK-4, in 15W-40 comes with 1200 ppm of ZDDP but it ALSO comes with a lot of detergent. Diesels make a lot of soot, and you want a good detergent to move that soot into the filter. You do not NEED a high detergent oil in your Bronco....but where else can you get the right ZDDP for $3.75 a quart? Racing Oils like Gibbs, and Valvoline, and motorcycle oils are fantastic. But not cheap. And keep in mind that you can have too much ZDDP. So if you want to buy some straight weight mineral oil, and blend your own mix by adding about $4.00 per quart of ZDDP, you are looking at $12-$15 per quart of something that is very likely WORSE than buying Valvoline VR1 at $10 per quart. So you might be tempted to do what @pbwcr recommends, but be prepared to pay more, and do a lot more work. (keeping in mind that the "better oil options" always existed. We were just led away from them...)

I would actually prefer 10W-30 high ZDDP, low detergent here in my classic flat tappet engine in mild CA, but I run Rotella 15W-40 because it's great AND cheaper.

 

[jamesroney]

So the rotella 15-40 with ck-4 is something I should stock up on for my 351w flat tapper engine? Excuse my ignorance but this in not a break in oil for but to be used after break in??

Yes. Unless you want to pay extra for racing oil. After January, 2027 the formula changes.

 

[jamesroney]

Yes high ZDDP. Great for a diesel motor, not so great for a 351 gas motor.
Better was is to use 10w30 and add your own ZDDP. That is what a lot of us did before better oil options became available.

It has a lot of detergent in it, but I'm not sure it's bad for a 351 gas motor. But certainly, there are better options.

Now if your old 351W has been running mineral based non-detergent motor oil and has a pan full of sludge, you absolutely do not want to start running a high detergent diesel motor oil package.

 

[73azbronco]

oil also oxidizes, it gets a little "burned" looking just sitting there for years. But is still the same oil.