ZDDP Additives for older vettes

[Don Mason]

Hey Guys, I'm sure this topic has been discussed before and I have just missed it, so please bear with me. I have read a couple of articles lately about motor oils and the lack of ZDDP additives in todays oils. According to the articles the omission of this additive can be particularily harmful to flat tappet cams and cause premature lobe wear and ultimate cam failure. Should I be using an additive in my '73 L-82? I use Castrol GTX 10-30 in the engine. As always thanks for the input.

 

[baxsom]

look into the shell rotella 5w40 synth or the 15w40 conventional.
it has all the zddp you need already in it.

or

buy a bottle of zddp plus and add it to any oil

 

[Vette79]

Mobile1 SUV oil contains a good amount of ZDDP. I purchased a 4pack of ZDDP off of Ebay not to long ago and will use it with every oil change.

 

[baxsom]

according their page
http://www.mobiloil.com/USA-English/MotorOil/Files/Mobil_1_Product_Guide.pdf

the truck/suv oil only has 800 ppm zddp

i didnt think that was enough

 

[Hib Halverson]

1) Avoid additives advertised as being solely for increasing ZDP content.

2) If a synthesized hydrocarbon synthetic is your choice, for engines with flat tappet cams which are in good condition as far as existing wear goes, Mobil 1 10W30 "High Mileage" is the best choice. It has enough ZDP such that the phosphorous content will be 1000 PPM.

Even better is an ester-based synthetic, Red Line 10W30 which has about 1100 PPM phos.

If you prefer a petro-based oil, Valvoline VR-1 10W30 Racing Oil is a great choice with 1200 PPM phosphorous.

 

[petes74ttop]

One more question about ZDDP.

Hi HH, I have used Valvoline Conventional Oil 10W30, are you saying VR-1 10W30 should be what I use from here on?
I only recently heard about the lack of ZDDP, thanks, PG.

 

[RMS73]

I switched to Shell's Rotella 15W40 oil. below is some info from Shell:
Info from the Shell Answer Man about the wear additives in Rotella the old CI-4 verus the new CJ-4 spec's.
He, actually a she, said

...........................CI-4..............CJ-4
Zinc.................. 1390 ppm.......1210 ppm

Phospherous.........1265 ppm.......1110 ppm

About 12% lower for the new oil, but much more than the regular car SM spec oil.

Roger

 

[Hib Halverson]

Hi HH, I have used Valvoline Conventional Oil 10W30, are you saying VR-1 10W30 should be what I use from here on?
I only recently heard about the lack of ZDDP, thanks, PG.

Is the Valvoline 10W30 you are using a GF-3 or a GF-4 oil?

Also, is the camshaft in your 74 stock/original or is it an aftermarket high-performance or racing cam?

 

[petes74ttop]

The oil is GF-4.
The motor is all stock, GM 10067353, installed in June 2002, about 31,000 miles ago. PG.

 

[Hib Halverson]

The GF-4 Valvoline is ok for a fully-broken-in stocker in good condition.

But, if you feel uncomfortable, the Valvoline VR-1 has a way more ZDP than you need and the Shell Rotella referenced above (as well as Chevron Delo 400) are between the two as far as ZDP.

But, again, with a stock engine, already broken-in and in good condition, you really don't have much to worry about.

I don't have specific data on all GF-4 products, but the limits are 600 PPM phosphorous minimum and 800 PPM maximum. My research (just recently and still in process) shows that the industry is generally going to 750 PPM for GF-4 products. When your car was new, mass-marketed engine oils were 700-900 PPM.

Where lower levels of ZDP are a problem is with: 1) engines having special, high-performance or racing flat tappet cams, 2) engines with valve springs having higher than OE tension, 3) engines using off-brand aftermarket valve lifters, or 4) new engines with new flat-tappet cams which are not yet, broken-in.

 

[JohnZ]

I switched to Shell's Rotella 15W40 oil. below is some info from Shell:
Info from the Shell Answer Man about the wear additives in Rotella the old CI-4 verus the new CJ-4 spec's.
He, actually a she, said

...........................CI-4..............CJ-4
Zinc.................. 1390 ppm.......1210 ppm

Phospherous.........1265 ppm.......1110 ppm

About 12% lower for the new oil, but much more than the regular car SM spec oil.

Roger

Same thing I use in my cars - any CI-4 or CJ-4 diesel oil (brand really doesn't matter - what matters is the API spec) will provide adequate protection unless you have an extreme situation like Hib notes in the last paragraph of post #10.

 

[Hib Halverson]

There is much urban legend in the car hobby about this valvetrain wear and ZDP issue.

There have been tons of Internet "articles" about it and many magazine articles, most notably, a piece by Marlan Davis in 'Hot Rod" several years ago. Coincidentally, both "Corvette Fever" and "Corvette Enthusiast" magazines have articles on this subject in their current, August, issues. Sadly, both contain some inaccuracies and the story in "Corvette Enthusiast" (a magazine to which I contribute) is, in my opinion, a significant offender, containing several statements about ZDP being "removed" or "eliminated" from engine oil along with the implication that the only solutions to the problem are pour-in additives.

In my opinion, those are significant falsehoods.

Fortunately, the Editor of "Corvette Enthuaist," Andy Bolig, is anxious to correct this problem and has under development a better-researched and more detailed, two-part series on the oil/cam wear issue.

 

[petes74ttop]

Thanks for the information, I'll get some CI-4 or some CJ-4 for the next oil change, PG.

 

[fine69]

I've been using the VR-1 stuff from Valvoline.. I get it from Advance Auto; it's cheap and works fine. I broke-in my cam with it, and so-far-so good... I haven't seized up yet!

Ralph

 

[JohnZ]

The latest (Summer 2008) issue of the NCRS "Restorer" magazine has an extremely well-researched and objective article on the subject, by Duke Williams.