Recent Topics
Going by HTHS
by JLTD. 02/21/19 02:59 AM
Quick Struts vs Replacing the struts by themselves
by das_peikko. 02/20/19 11:50 PM
Walmart Oil clearance # 2
by GMguy84. 02/20/19 11:14 PM
ST Syn in a TGDI?
by BTLew81. 02/20/19 09:52 PM
The Virus That Kills Drug-Resistant Superbugs
by StevieC. 02/20/19 09:50 PM
Opinion Of Dodge Nitro
by Warstud. 02/20/19 09:26 PM
Cheap first car
by LeakySeals. 02/20/19 09:08 PM
Grand Caravan break in
by pda1122. 02/20/19 09:07 PM
Million mile Lexus
by Skippy722. 02/20/19 08:57 PM
Antioxidant additive overdose
by xomyeusun. 02/20/19 08:50 PM
F15 Arrested Landing at Portland.
by PimTac. 02/20/19 08:43 PM
Why is Mobil 1 0w30x1 rated higher than most
by spiderbypass. 02/20/19 08:14 PM
Castrol Confusion
by PWMDMD. 02/20/19 07:13 PM
Crashed the Volt this morning...
by 14Accent. 02/20/19 06:55 PM
Best place to file online for Fed taxes?
by Vern_in_IL. 02/20/19 06:47 PM
vavoline instant oil change
by silver1. 02/20/19 06:23 PM
Newest Members
alienyouth33, RoyFJ, Intell77, RA_TJ, tiberius54
67294 Registered Users
Who's Online Now
54 registered members (billt460, AndyB, Astro_Guy, 2015_PSD, 97K15004WD, 5 invisible), 639 guests, and 58 spiders.
Key: Admin, Global Mod, Mod
Forum Statistics
Forums67
Topics284,588
Posts4,872,977
Members67,294
Most Online2,548
Feb 16th, 2019
Donate to BITOG
Print Thread
Hop To
Zinc vs molybdenum #4806296
07/05/18 08:43 PM
07/05/18 08:43 PM
Joined: Mar 2010
Posts: 654
NY
mx5miata Offline OP
mx5miata  Offline OP

Joined: Mar 2010
Posts: 654
NY
What's zinc and molybdenum, how they differ or if have similarities?


NAPA FULL SYNTHETIC 0w20 Partsplus oil filter
Wix air filter
Re: Zinc vs molybdenum [Re: mx5miata] #4806301
07/05/18 08:47 PM
07/05/18 08:47 PM
Joined: Mar 2017
Posts: 7,563
...
PimTac Offline
PimTac  Offline

Joined: Mar 2017
Posts: 7,563
...


Cannot see signatures any longer so it doesn’t matter.
Re: Zinc vs molybdenum [Re: mx5miata] #4806303
07/05/18 08:49 PM
07/05/18 08:49 PM
Joined: Mar 2010
Posts: 654
NY
mx5miata Offline OP
mx5miata  Offline OP

Joined: Mar 2010
Posts: 654
NY
Okay


NAPA FULL SYNTHETIC 0w20 Partsplus oil filter
Wix air filter
Re: Zinc vs molybdenum [Re: mx5miata] #4806314
07/05/18 09:01 PM
07/05/18 09:01 PM
Joined: Aug 2008
Posts: 3,376
Where the wind comes sweepin'
Reddy45 Offline
Reddy45  Offline

Joined: Aug 2008
Posts: 3,376
Where the wind comes sweepin'
I'm not a pro at this stuff, but to give you a somewhat useful answer...

Moly provides cushion/lubrication between SLIDING surfaces (like cam journals). It breaks apart at very microscopic levels and retains its form, and glides between opposing surfaces.

Zinc.. I think works best when in combo with Phosphorous? ZDDP which is a well known anti-wear additive. I forgot the actual mechanism but it constantly forms a sacrificial layer between surfaces that takes the brunt of the friction.. something like that.

Re: Zinc vs molybdenum [Re: mx5miata] #4806330
07/05/18 09:16 PM
07/05/18 09:16 PM
Joined: Mar 2017
Posts: 7,563
...
PimTac Offline
PimTac  Offline

Joined: Mar 2017
Posts: 7,563
...
There is a lot of information right here on BITOG.


Cannot see signatures any longer so it doesn’t matter.
Re: Zinc vs molybdenum [Re: Reddy45] #4806427
07/06/18 03:58 AM
07/06/18 03:58 AM
Joined: Mar 2010
Posts: 654
NY
mx5miata Offline OP
mx5miata  Offline OP

Joined: Mar 2010
Posts: 654
NY
Originally Posted By: Reddy45
I'm not a pro at this stuff, but to give you a somewhat useful answer...

Moly provides cushion/lubrication between SLIDING surfaces (like cam journals). It breaks apart at very microscopic levels and retains its form, and glides between opposing surfaces.

Zinc.. I think works best when in combo with Phosphorous? ZDDP which is a well known anti-wear additive. I forgot the actual mechanism but it constantly forms a sacrificial layer between surfaces that takes the brunt of the friction.. something like that.


Thank you.


NAPA FULL SYNTHETIC 0w20 Partsplus oil filter
Wix air filter
Re: Zinc vs molybdenum [Re: Reddy45] #4806450
07/06/18 05:05 AM
07/06/18 05:05 AM
Joined: Nov 2006
Posts: 20,998
MA, Mittelfranken.de
Trav Offline
Trav  Offline

Joined: Nov 2006
Posts: 20,998
MA, Mittelfranken.de
Originally Posted By: Reddy45
I'm not a pro at this stuff, but to give you a somewhat useful answer...

Moly provides cushion/lubrication between SLIDING surfaces (like cam journals). It breaks apart at very microscopic levels and retains its form, and glides between opposing surfaces.

Zinc.. I think works best when in combo with Phosphorous? ZDDP which is a well known anti-wear additive. I forgot the actual mechanism but it constantly forms a sacrificial layer between surfaces that takes the brunt of the friction.. something like that.


That's how I understand it also. I use Rislone ZDDP additive a lot, it also contains Phosphorous, half a bottle in a 5qt sump brings the SN oils up to 1200 ppm and the bearing wear levels dropped significantly in one particular high output engine, so it does a lot more than than just protect the cam and the numbers prove it.

Like anything else though people get carried away, if 6 oz works well then the who bottle will work better (it doesn't) and that's where the problems start. It is not needed in new engines that use different bearing materials and OHC with light loads but engines that spec SF, SG and so on really seem to benefit from a little extra zinc.


ASE L1, Master. Deutsch Meisterbrief.
Re: Zinc vs molybdenum [Re: mx5miata] #4806483
07/06/18 06:09 AM
07/06/18 06:09 AM
Joined: Jul 2015
Posts: 4,676
Down Under
SR5 Offline
SR5  Offline

Joined: Jul 2015
Posts: 4,676
Down Under
It depends on the concentration and the actual formulation. Plus there is certainly some overlap in their job

But I think of moly as a friction reducer that makes an engine run smoother.

For zinc (ZDDP) it is an anti-wear agent that protects the metal in high pressure parts of the engine when the oil film is squeezed out.

They both coat the metal surface, the difference is in the force required to remove the sacrificial layer formed. Lower force for a friction reducer & higher force for a wear protector.


---------------------------------------------------------------------------------
Castrol GTX Ultraclean 15W40 A3/B3 + Wesfil-Cooper Z154
Re: Zinc vs molybdenum [Re: mx5miata] #4806549
07/06/18 07:25 AM
07/06/18 07:25 AM
Joined: Jan 2018
Posts: 176
Central Texas
Brian553 Offline
Brian553  Offline

Joined: Jan 2018
Posts: 176
Central Texas
ZDDP is consumed from the oil blend at the surface of contact between to surfaces. It is activated by high heat/pressure and the reaction creates a compound on the surface that can plastically deform. The film can only plastically deform so much before fracturing, or spalling off the surface. Moly FMs can step in (and step in well for the pressures/temperatures of these environments) to reduce friction between the two surfaces. This then helps to reduce the shear stress in the film, thereby helping to reduce deformation and spalling of the film. Once spalled, the film is "consumed," or lost its ideal functional purpose. This is as best that I understand it; I am not a tribologist.

Re: Zinc vs molybdenum [Re: mx5miata] #4806621
07/06/18 08:33 AM
07/06/18 08:33 AM
Joined: Jun 2002
Posts: 19,696
Iowegia - USA
MolaKule Offline
MolaKule  Offline

Joined: Jun 2002
Posts: 19,696
Iowegia - USA
Originally Posted By: mx5miata
What's zinc and molybdenum, how they differ or if have similarities?


Brian553 gave an excellent explanation.

Molybdenum and Zinc are basic elemental metals.

I think you are referring to the ZDDP (Zinc DiarylDiThioPhosphate) and the MoDTC (Molybdenum DiThioCarbamate) in engine oils and other lubricants. ZDDP is a molecule in the form of an ester which is composed of Phosphorus, Zinc, and Sulfur atoms.

The "Moly" is primarily a Friction Modifier agent in additive packages whereas ZDDP is a Multi-Functional agent in Additive packages. ZDDP acts as both an Anti-Wear and Anti-Oxidant.

Last edited by MolaKule; 07/06/18 08:37 AM.

"I can't change the direction of the wind, but I can adjust my sails to always reach my destination." Jimmy Dean
Re: Zinc vs molybdenum [Re: mx5miata] #4806717
07/06/18 10:22 AM
07/06/18 10:22 AM
Joined: Feb 2003
Posts: 678
Chicago
RichR Offline
RichR  Offline

Joined: Feb 2003
Posts: 678
Chicago
Brian553 its nice to see great information.

And it's nice to have MR Kule back on board!


A co-worker said
I have an oil fetish
Re: Zinc vs molybdenum [Re: mx5miata] #4807004
07/06/18 04:34 PM
07/06/18 04:34 PM
Joined: Oct 2005
Posts: 5,156
Fredericksburg, VA
JAG Offline
JAG  Offline

Joined: Oct 2005
Posts: 5,156
Fredericksburg, VA
A very good paper on ZDDP:
https://pdfs.semanticscholar.org/e2dc/da55f2a51bde3dabb2ef06543fc401d61ed4.pdf

Paper on ZDDP and MoDTC:
https://www.mgexp.com/phile/1/291112/ZDDP_Paper_Leeds.pdf

There is something that I think does not receive enough recognition by people who discuss ZDDP. Many will just look at Zn and P concentrations and think that is all that matters, without considering the reactivity of the ZDDPs varies by type. Its stated in the second paper above:
The type of ZDDP is defined by the organic alcohol used to synthesize it: alkylphenols for aryl ZDDP, primary alcohols for primary ZDDP (CH3CH2CH2CH2O), and secondary alcohols for secondary ZDDP (CH3 CH2 CH(CH3 )O). Primary and secondary alkyl ZDDPs have different thermal stabilities, primary ZDDP being more thermally stable than secondary ZDDP. Their different thermal stabilities affect the rate of film formation [5860] and in turn the antiwear performance [61]. In general, the primary ZDDPs are preferred for use in diesel engines while the secondary ZDDPs are preferred for use in gasoline engines [62].

Re: Zinc vs molybdenum [Re: mx5miata] #4807054
07/06/18 05:28 PM
07/06/18 05:28 PM
Joined: Mar 2018
Posts: 143
Hammehead Offline
Hammehead  Offline

Joined: Mar 2018
Posts: 143
Secondary esterified ZDDP poisons Catconverter more readly than primary, thats why is used in minor concentrations. Primary are more expensive and secondary are the ones most used in bottle additives.

Last edited by Hammehead; 07/06/18 05:30 PM.

ToYota Corolla XEI 2010 1zzfe
Kawasaki Ninja ZX9R B4
Taurus GL Vulcan
Citroen C5 phase I
I used to use syn, now whatever is on sale and never had problems. This noob knows stuff.
Previous Thread
Index
Next Thread

Moderated by  ekpolk 

BOB IS THE OIL GUY® Powered by UBB.threads™