PYB, Moly content and high miles

Status
Not open for further replies.
Joined
Feb 17, 2007
Messages
3,998
Location
Clermont, Florida
This post is about the 2001 Dodge Dakota in my signature. It is a V6 3.9 liter with a 5 speed. It has 148,400 miles on it now. I have been using Quaker State conventional 10W30 for the last 18 months. Before that I used Napa and Carquest 10W30 conventional. Prior to that I used Valvoline White Bottle and also did a few OCI's with Maxlife 10W30.

All of the oils I have used did fine, as far as I can tell. I have an oil change coming up soon. I read on here that PYB has a lot more moly in it than other conventional oils. I have also read that the QS GB I have been using has more boron than other oils, and boron is said to be very good for engine seals.

My question is this: PYB obviously has a lot more moly. I wonder if a higher moly content is better for my higher-mileage V6? Would more moly help it run any better/smoother/with less noise? Does a higher moly content protect higher mileage engine internals any better than conventional oil with less moly?

I also read the PYB has a better TBN, and if I understand it correctly it basically means to me that the oil stays in its grade and provides good protection longer than other oils with a lower TBN.

I am not interested in using a "High Mileage" specific oil. I did not like the way my truck ran with Maxlife. It made my truck run a bit sluggish and caused a drop in my gas mileage. I am trying to keep my truck running its best and make it last as long as possible. I would make the switch to PYB if the higher moly and any other qualities would help.

I did do a search on my moly question, but all it really returned was posts about high mileage oils. I would appreciate your info here, or if there are posts I missed maybe if you guys have any links I can check out.

Thanks for your help on this.
 
Don't worry about an oil that says "high Mileage" on it unless you have consumption issues.

Regular oil changes protect your engine. A quality oil helps more. Just use the PYB. Moly won't save your engine in and of itself.
 
Last edited:
TBN has nothing to do with an oil "Staying in grade" - TBN stands for "Total Base Number" and is related to an oil's ability to prevent becoming acidic, and is also related to an oil's overall detergency, or ability to keep contaminants in suspension.

PYB will, in general, stay in grade as long as an engine isn't hard on oil - which your Dodge isn't.
 
OK, thaks for the help and I apologize for my ignorance on the specs and characteristics of the components and compounds found in oil. I believe I will just use the remaining quarts of QSGB I have in my stash. QSGB has done a fine job in my engine so far. Thanks again.
 
Originally Posted By: Jimmy9190
I believe I will just use the remaining quarts of QSGB I have in my stash. QSGB has done a fine job in my engine so far. Thanks again.


I doubt you'll have any problems with QS. I've used many, many bottles of it over the years. I'd be using it in my G had I had enough in stock or had it gone on sale before the PYB did. I'm happy with either of them.
 
I do like how my truck runs on QS. Quiet and smooth and I get good gas mileage and power with it. Even at 148K my truck only burns about half a quart of oil about every 2500 miles.

I bought a few cases of QS back when AAP had it on sale with Purolator filters. This was back before all the rebate nonsense started. I am very satisfied with QS. I know it's not exactly the same as PYB but it is pretty darn close.

Thanks for your help.
 
You original question is actually quite a common misconception about the effect of increased Moly in oils, and you aren't alone in reading this and hoping that increased moly would help your engine. The adage "if some is good, more must be better" typically doesn't apply with any oil technology - no matter what the prevailing opinions may tell you. This is demonstrated very well with the current thick vs thin debate because higher viscosity is proving not to be better in most instances.

As CATERHAM explained, Moly is an ANTIWEAR additive and has a tendency to lower the coefficient of friction (CoF) of an oil, and generally helps to improve fuel economy. Molybdenum compounds react in the oil environment to create a MoS2 film that functions well in reducing the CoF. However; due to the oxidative dehydration of the MoS2 during the oil life this function is difficult to sustain over extended oil drains. The use of anti-oxidents and the presence of ZDDP helps to improve the life of MoS2 layers; but overall you will see little change in the degree that moly functions by small increases in the Moly compound itself (the difference between PYB and QSGB for example), as even with Moly still in the oil, the effect it has due to dehydration is minimized over time.

I suspect that the use of Moly in grease applications and its relative cost effectiveness is part of the reason that it has become a byword in the industry for wear protection when the truth is that a balanced formula containing a blend of effective AW/EP additives is the answer to better protection.

Every engine is different and if you are happy with the results you are getting with QS then keep using it; both are good oils, I know that alot of BITOG users extol PYB over QS, but my experience puts them on a relatively level playing field.
 
Thanks for the info, Solarent. I am going to pick up some PYB and Puro Classics for my girlfriend's Honda Accord before the AAP sale ends this month. Her car will also need an oil change soon. Even with the rebate silliness, $14.00 for 5 quarts of PYB and a Puro Classic is still a very good deal. I may even stash a PYB oil change for my truck while I am at it.
 
I don't believe the oil mfrs put more moly in because it has no effect or benefit.
I certainly like the improvements with Lubro Moly additive.
 
I personally think higher moly content is good for ANY engine.

I think the science behind moly, and how it reduces wear in engines, is one of the best-established facts we have about an engine additive in oil.

I don't 'know' as much about boron as some others do - I'm still a bit confused about exactly what it does best - clean, or reduce wear?

That said, both QS and PYB have a significant amount of both moly and boron in them, so both will prevent wear in any engine better than many oils.

I went with QS for my last fill, even tho PYB was a similar price, b/c the QS 5W-20 has just slightly better cold-cranking values - yeah, I split hairs!
 
I like some of the HM oils. Like mobil super 5000 It has a bunch of zinc and its a syn blend that is fairly affordable and does a pretty high mileage. I think any syn blend would be better than the conventional and keep your engine running good longer and better than the PYB or The other two you were using. And the mobil super has titanium the new moly. And I just noticed its a bit thinner on top and bottom so you could get .000000003% better fuel mileage.
 
Originally Posted By: Jimmy9190
I am going to pick up some PYB and Puro Classics for my girlfriend's Honda Accord before the AAP sale ends this month. Her car will also need an oil change soon. Even with the rebate silliness, $14.00 for 5 quarts of PYB and a Puro Classic is still a very good deal. I may even stash a PYB oil change for my truck while I am at it.


I went to Walmart tonight, trying to do some Christmas shopping. I made two trips up and down the oil and filter aisle, they had PYB on the shelf for $4.17 per quart, QSGB was $3.94 per quart. I don't use the 5+ quart jugs so I did not pay much attention to them.

The AAP deal for $20.00 for 5 quarts PYB and a Puro Classic ($14.00 after the $7.00 MIR) definitely is the better bargain. 5 qts x $4.17=$20.85, and that price is just for the oil, it does not include a filter. Even without the rebate, AAP still has the better price. I am going to pick up a PYB/Puro Classic deal for my truck and her car at AAP this week. I do have some QS stashed but I really would like to try PYB because I have read so many good things about it here on BITOG. I don't know if I will be able to tell any real differences in PYB compared to QS, but it's oil change time and why not try a different oil, one that is recommended by so many of us here and is many of us say it is the best conventional oil?

If AAP were not having the PYB deal I would probably just use my QS stash for this oil change coming up on Saturday and not worry about experimenting. I just want to try the PYB and see how it does. I am sure it will do just fine and I will probably not be able to tell any difference between QSGB and PYB. I will probably post back here after I get the oil change done, but it is hard to really tell much difference on a brand new fill of oil. I know my own engine always sounds smooth and quiet when I first change my oil.

Thanks for all of your help on this.
 
Originally Posted By: Y_K
Could you expand on dehydration a little more, please?


Moly content in oil typically comes from MoDTC (molybdenum dithiocarbamate) or MoDDP (molybdenum dithiophosphate) and it reacts with surface metals to form Molybdenum disulphide (MoS2) which is what creates the sacrificial wear layer. However over time the exposure of the molybdenum additives to oxygen changes the surface layers to Mo03 which is what is referred to as oxidative dehydration, this reaction takes time and so that is why the good fuel economy achievable with MoS2 in oils is hard to sustain over long service periods. (Basically oxygen + moly = very little wear protection). Water can also contribute to the deterioration of MoDTC and it can be difficult to see the effects of Moly continue beyond the 4000 mile mark. Using antioxidents can help prolong the effect that Moly has and so does our friendly ZDDP. So depending on what the additive package has blended with it Moly content (MoDTC) can still be very high but be basically inactive due to oxidative dehydration.

LONG STORY SHORT - Like Addyguy stated - moly is good - and well documented as effective, and having more is in no way a bad thing; but it isn't the be all end all ingredient in additive packages.

As far as BORON goes - boron nitride falls into the category of "solid" lubricants (the same as MoS2) and can function as a wear layer in a similar way to Moly; organic boron compounds also can function as dispersants (which help to hold contaminants in suspension and assist in the removal of oxidative biproducts - hence the detergent factor). It is one of those additives that can perform multiple functions but has been traditionally less popular due to cost efficiency vs MOLY and ZDDP.

There are some good threads on here where BORON is studied in depth that are good reads if you are interested, and probably worded better than I could do.

The new advent of Titanium compounds as antiwear additives fall under the same category as ZDDP (metal-phosphorus-sulphur additives) but react differently than zinc does. I have yet to see any good research papers published on Titanium, so if anyone has a good link or suggested place to go I would love to see it.
 
I did change my oil on Saturday, I used PYB 10W30. I know it is a fresh oil change and it is too soon to really tell much about it yet but my engine is definitely quieter and sounds a lot better, running very smooth on the PYB. Truck runs very well and sounds good under the throttle. That has to be from the increased moly content in PYB.

PYB is a great oil. I also noticed it has a more golden-clear color, almost like Valvoline. The QS I use is a lot darker brown. I know that doesn't matter either, it is just something i noticed.

Maybe my truck sounds better and feels better when I drive now beacuse the PYB I bought is SN, and the QS I had been using from my stash was SM rated. I don't know. I like the smooth quiet operation of my engine on the PYB though. I also bought 5 quarts of PYB 5W20 for my gf's Honda for her next oil change coming up soon. PYB will probably help her car run and sound better too.
 
Last edited:
Glad the placebo effect is working for you.
grin.gif
 
Status
Not open for further replies.
Back
Top