STP vs ZDD Plus

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Hey guys,

Is it worth it to spend the extra money for the ZDD Plus zinc additive, or is the $3 bottle of STP fine? I've seen the voa of the STP and the Zinc content, I'm just wondering if there is something that would make one better than the other?

Thanks
 
I don't know, but the Redline breakin additive has tons of zddp, something like you would only need 2 oz for a whole crankcase IIRC. There are threads on it.
 
Originally Posted By: ADFD1
Any down side to too much ZDDP? Say 1 ounce/qt of the Red Line add?

AD


Yes! Over 2000 ppm (I'm not sure whether Zn or P, use Zn to be safe since it's ~10% higher) can attack camshaft lobes and cause catastrophic chunking. Be very careful with these additives. For example, ZDDPlus has 71800ppm Zn, 51500 ppm P. 30ml in 5qts will raise Zn ~450ppm, P300ppm. In a somewhat typical fairly weak 600ppm SM oil, that will raise Zn/P to "safe" levels of ~1100/900. Certainly add no more than 1/2 bottle (60ml) to get levels up to ~1600/1200. Remember, many Mobil 1s as an example are 900/800 at a minimum, HDEOs range from 900/800 (some CJ4s) to 1400/1300 (some CI4s).
STP was analyzed on the 1st page of the sticky of VOAs. It's P carefully, use one of the more potent single-ingredient ones like ZDDPlus or Redline, know exactly what its' concentration is AND your oil's concentration, and do your sums carefully, recheck at least once. Too much of a good thing is very bad!
Maybe download (for $15) and read SAE technical article 2004-01-2986 "How much ZDP is enough", first.

Charlie
 
Originally Posted By: m37charlie
Originally Posted By: ADFD1
Any down side to too much ZDDP? Say 1 ounce/qt of the Red Line add?

AD


Yes! Over 2000 ppm (I'm not sure whether Zn or P, use Zn to be safe since it's ~10% higher) can attack camshaft lobes and cause catastrophic chunking. Be very careful with these additives. For example, ZDDPlus has 71800ppm Zn, 51500 ppm P. 30ml in 5qts will raise Zn ~450ppm, P300ppm. In a somewhat typical fairly weak 600ppm SM oil, that will raise Zn/P to "safe" levels of ~1100/900. Certainly add no more than 1/2 bottle (60ml) to get levels up to ~1600/1200. Remember, many Mobil 1s as an example are 900/800 at a minimum, HDEOs range from 900/800 (some CJ4s) to 1400/1300 (some CI4s).
STP was analyzed on the 1st page of the sticky of VOAs. It's P carefully, use one of the more potent single-ingredient ones like ZDDPlus or Redline, know exactly what its' concentration is AND your oil's concentration, and do your sums carefully, recheck at least once. Too much of a good thing is very bad!
Maybe download (for $15) and read SAE technical article 2004-01-2986 "How much ZDP is enough", first.

Charlie


How about adding 5 oz of the Red line break in add to a 5 qt sump effect a high quality SM oil? Would it put ZDDP to a dangerous level?

AD
 
I don't know. What is the Zn and P content, and what else is in it?
And the article says that one probably doesn't need >600-800ppm P for anything except high performance flat tappet engines with high valve spring pressures. OTOH, why do HDEOs have 800-1300 ppm P?

Charlie
 
Originally Posted By: Jdblya
So how would adding the STP to say 6 qts of oil that is SL Rated affect the level?


Take the difference between STP (2000 ppm Zn) and your oil's Zn (let's say 700) and divide by dilution factor. If STP bottle is 1 pint (?), and you already have 6qts, dilution factor is 6.5/0.5 = 13. (2000-700)/13 = 100 ppm increase. Not much, plus you just increased your viscosity an unknown amount.

Charlie
 
Originally Posted By: Jdblya
16oz to 4.5qts will bring zinc to 5000ppm. That is a lot.
Use only 2 to 4 ounces per crankcase fill. 5000 ppm is wayyyyyyy toooooo much! You make out on this one because one bottle will last 4-8 oil changes. Calculate it so that you boost only to about 1200 ppm, no need to go higher.
 
Originally Posted By: TallPaul
Originally Posted By: Jdblya
16oz to 4.5qts will bring zinc to 5000ppm. That is a lot.
Use only 2 to 4 ounces per crankcase fill. 5000 ppm is wayyyyyyy toooooo much! You make out on this one because one bottle will last 4-8 oil changes. Calculate it so that you boost only to about 1200 ppm, no need to go higher.


How about 4 ounces to 5 qts of the RL additive? Will that hurt an engine if added to one of the better oils?

AD
 
Originally Posted By: [RT
ProjUltraZ]check out the Redline break-in additive table on this page


Good stuff, 1 oz/qt of oil should boost the ZDDP nicely, and not cause any problems. Give Redline a call their tech people are very good.
 
Looks to me like ZDDPlus and Redline are the only products I'd add myself, in carefully calculated quantities so as not to exceed 1600 ppm Zn, 13-1400ppm P. I'm curious about the "other ingredients" in the RL.

Charlie
 
Originally Posted By: m37charlie
Looks to me like ZDDPlus and Redline are the only products I'd add myself, in carefully calculated quantities so as not to exceed 1600 ppm Zn, 13-1400ppm P. I'm curious about the "other ingredients" in the RL.

Charlie


Give them a call, they're great, and willing to help, no attitudes from them!
 
To be honest, I wanted to to add the stp to my amsoil marine oil to bump up the ZDDP, and as far as the viscosity, I would not really mind it if was a little heavier than the 10w30 that I am putting in it. However, Amsoil tech just sent me this

The ZDDP level in WCT is about 1300 ppm.

I may still add a bottle of STP to it just to see how it does. A little bump in ZDDP wouldn't make a huge difference, but again I would not mind having a slightly higher viscosity either. I supposed I could just use the Amsoil 10w40 marine, but originally my engine called for 30wt.
 
I have been told that the STP made today is much lower in zinc/phos then it used to be, I just would not use it. If you do not want to use ZDDPlus just buy Schaffers or Redline, etc... Many oils that you can use that have higher zinc/phos levels.
 
Even the somewhat maligned (by some) CJ4 HDEOs have a very liberal 1200ppm P limit. The Europeans are behind us on diesel emissions, Euro 6 is close to EPA 2010 but doesn't come into effect till 2013. However, they are ahead of us on diesel oils to adapt to low emissions. ACEA E9 is virtually identical to CJ4 but ACEA E6 has a limit of 800ppm P and 0.3% S (instead of 0.4% for E9/CJ4). That's to make the urea/SCR cat and oxy-cat part of the DPF last longer. E6 is supposed to be low maintenance/superlong drain/superlow wear. I'd have to be convinced regarding the low wear because of the low low P level.
Any diesel oil in this country has more than enough ZDDP for almost any application.

Charlie
 
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