ZDDP

I didnt realize this but API is trying to phase out wear metals in engine oil. The currnet SF spec has it down to 1/3 of what it was 15 years ago. I used to make oil for Amalie and now it doenst matter what brand you chose, Mobil, Exxon, by law they all have to limit the Zinc dithio phos. For $10 a crankcase this might be worth adding below. it triples the levels of Zn and P. Of course it causes cancer in lab rat though...


2 ZDDP MAXX ENGINE OIL ZDDP ADDITIVE ZINC & PHOSPHORUS | eBay
 

Randy V

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I wonder if it has more ZDDP than does STP?

Been using the later now for years.. They've been pulling the Zinc out of motor oil for the last half dozen years or so... Some truck oils still have a fair bit in them, but I've also heard that they are pulling it out of those oils too...
 
I'm using Royal Purple and called their tech line to make sure they use additives like ZDDP. They said they have a proprietary additive that offers high pressure protection. I may call back as I talked to them a couple of years ago.
 

Mike

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Doesn't the off-road only oils like Valvoline VR1 Racing Oil still have all the "dangerous" stuff in it?
 
Hot Rod mag ran a thorough article on this a couple of years ago. From what I recall, understanding this was critical for builders/owners of engines with solid lifters.
 
We were talking to a prominent LS engine builder at the IMIS trade show.
He said the oils for diesel engines still have the zinc, & that is what he recommends. I am curious of how to find out how much zinc an oil has? An additive may be good insurance.
 
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We were talking to a prominent LS engine builder at the IMIS trade show.
He said the oils for diesel engines still have the zinc, & that is what he recommends. I am curious of how to find out how much zinc an oil has? An additive may be good insurance.
Yes,

Most diesel oils still have a fair amount of Zinc (Chevron DELO, Shell Rotella, etc.) however they are designed and engineered for engines that have a max RPM of 3000 and even less (2400 or less) in the case of the 13 and 15 liter six cylinder heavy duty engines. The diesel oils have a limited amount of anti-foam additive and will start to foam up if you are turning 6000 RPM and up so not a good track day choice.
 
Yes,

Most diesel oils still have a fair amount of Zinc (Chevron DELO, Shell Rotella, etc.) however they are designed and engineered for engines that have a max RPM of 3000 and even less (2400 or less) in the case of the 13 and 15 liter six cylinder heavy duty engines. The diesel oils have a limited amount of anti-foam additive and will start to foam up if you are turning 6000 RPM and up so not a good track day choice.
pretty dry readign but i think api says it must be under 0.08% (800ppm) Phos for the current API-SN spec

http://www.api.org/certifications/engineoil/pubs/upload/150916thAdd10308forprint-2.pdf

Or, this is the marketing pitch from ZDDP maxx:

ZDDP CREATES A BOUNDARY LAYER BETWEEN TWO METAL PARTS THAT PROTECT THEM FROM DIRECT CONTACT, IF THERE IS NOT ENOUGH ZDDP THE PART BECOMES UNPROTECTED AND THE PART WILL FAIL. API SM RATED OILS DO NOT HAVE ENOUGH ZDDP TO PROTECT A PRE 1996 ENGINE,OR NEW RACING . ZDDP IS A EXTREME PRESSURE ADDITIVE THAT PROTECTS DRIVE TRAIN PARTS, CAM, LIFTERS, VALVE, PISTON RINGS, TURBO CHARGERS. MORE CONCENTRATED AND CHEAPER THAN ZDDPLUS. ZDDP MAXX TREATS 5 QUARTS OF OIL AT OVER 1800 PPM PHOSPHORS AND 2500 PPM ZINC. API RAITED SF OLIS ONLY EVER HAD 1300 PPM PHOSPHORUS MOST API SM OILS HAVE 600 TO MAX 900 PPM PHOSPHORUS ZDDP MAXX DELIVERS OVER TWICE THE ZDDP COMPARED TO THE BEST SM OIL. SF OIL IS RECOMENDED FOR PRE 1990. WARNING ZDDP MAXX HAS A VERY STRONG SMELL DUE TO IT BEING A CONCENTRATE. ALL PARTS OF ZDDP MAXX IS MADE IN THE USA.
 
I have owned a Jensen Healey for a long time and this has been a topic of some concern on the JH forums for quite a while. That Lotus 907 engine does not care at all for modern oils. Valvoline was the recomended oil, but alas, even they are lacking now. I have been using an additive for 3 years now.
 

Julian

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It's tough to keep up with which oil brands have the correct Zn & P levels for older flat tappet engines; any bottle showing SL, SM & SN designations will likely not.

There is some discussion on whether high levels of Zn & P are even necesary after the cam is broken in, IMO yes absolutely and it's good insurance anyway. There is other discussion on whether the add in ZDDP additives disperse/suspend adequately to be of significant use, but I have to admit that may be some marketing noise from the competing oil products that already have it.

Brad Penn Grade 1 oil has high levels of Zn & P and is a dino/synthetic blend. I was using it and then switched after my local dealer gave up the franchise. I now use AMSOIL and they have Z-ROD products specifically for classic cars or their racing oils still have high levels of Zn & P (as do most manufacturers Racing branded 'not for street use' oil). If you join AMSOIL's preferred customer program ($20/yr) you get better pricing and their shipping is pretty nominal in case you don't have a dealer close by.

Bob is the Oil Guy is a good resource for info on oils and additives.
 
Michael,

I will be more specific in that the less expensive 20-50 that was commonly used in these cars is now lacking. Due to the somewhat looser tolerances in these fine mid-seventies British engines the heavier weight oil was preferred. I still use it, just with an additive now.
 
Michael

exactly the way to look up the datas. One can find the datasheets of each branded oil pretty easy. I´m using VR1 since years on every of my engines, without any problems.
The only one case i used Castrol RS gave me a engine with damaged tappets and cam ( 13.000 RPM Twin race bike). Switched back to VR1, cam and tappets locking like new since then.
In my high RPM 331 i used VR1 plus addtional ZDDPLUS to arrive at the recommanded 2500 ppm ( from the standard 1400ppm VR1 still have)of Zinc for this kind of solid lifter engine.

I also do fancy higher viscosity oils like that 20 W-50 VR1. No need for a 0 W-30 if you dont drive and start the car in winter or below 10°C. If so preheat it a bit with a heater under the oilpan and you are fine.

TOM
 
I'm probably beating a dead horse as this topic been on here before. I'm sure most teh avid gearheads know about the need for ZDDP but its worth mentioning for those of us that are getting back into it. I found this pdf from Howards previosu thread that shows the steady decline in Zn/P. also found this below on a Ford blog. looks like STP might be a bit low if you factor in SN API, certainly better than nada...

(re)
It shows STP to have 1959ppm of zinc and 1814ppm of phosporous. So, that would be diluted to 391ppm zinc and 362ppm phosphorous when added to five quarts of oil, right?

Rotella 15-40 which seems to be accepted as having enough zinc to prevent flat tappet wear contains roughly 1200ppm zinc and 1100ppm of phosphorous.

Current passenger vehicle oils on the market now are SM spec and contain approx 870ppm of zinc and 800ppm of phos, therefore adding a bottle of STP should bring that level up to roughly 1261ppm zinc, and 1162 phos.

The conclusion I've arrived at here is that running with a bottle of STP added to SM spec oil is as effective as running 15-40 diesel oil in our effort to maintain the service life of flat tappet cam engines.

Interestingly, I've also read that adding STP to 10-30 will increase viscosity to about 15-40. So, adding STP to 5-20 should bring it up to 10-30 if you are looking to maintain that viscosity.
 

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