PAO vs. ESTER oils? which one is better?

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depends, they both have drawbacks and are used in combination to balance out the best.

.........................PAO....ESTER
Additive solubility......bad....good
VI.......................good...medium
Hydrolitic stability.....good...bad
low/high vis grades......good...medium
cost.....................low....high

other diferences but you get the idea.
bruce

[ July 23, 2005, 11:08 PM: Message edited by: bruce381 ]
 
quote:

.........................PAO....ESTER
VI.......................good...medium
Hydrolitic stability.....good...bad
low/high vis grades......good...medium


I thought ester had a higher viscosity index that PAO.

I think hydrolitic stability relates to the type of ester and may not be an issue with that used in motor oil.

Not sure what "low/high vis grades" means.
 
quote:

.........................PAO....ESTER
Additive solubility......bad....good
VI.......................good...medium
Hydrolitic stability.....good...bad
low/high vis grades......good...medium
cost.....................low....high

Bruce381 is providing us with insights based on his many years as a professional working with lubricant/oil formulations.

I think he is trying to provide a "25 words or less" answer to a complicated question.

I just re-read the "About Esters" page at the Hatco site and noted the Hatco comment that one drawback with esters is the attraction for water.

As far as VI index, the Cognis site lists multiple ester products in the 130-140 index range, which is same as PAO to my knowledge.

As Bruce indicates, PAO's get the nod based on available viscosity grades, as PAO's typically run 4-8-10-25-40 cSt and up to 150 cSt.
 
quote:

Originally posted by Blue99:
Bruce381 is providing us with insights based on his many years as a professional working with lubricant/oil formulations.

pat.gif
Of course. I should have viewed his profile. Anyway, thanks for elaborating on his points. Then Redline (for example) has treated their oil somehow to eliminate the water attraction issue, right?
 
The blended PAO/Ester basestocks have the best overall physical/chemical properties - and the take well to additive packages that are developed for conventional lubricants.

Note that the "Group III" synthetics simply replace the PAO portion of the basestock blend with the less expensive Group III, hydroisomerized oil. So these are more accurately called Group III/Ester blended base stocks.

Pure ester based synthetics more most useful to make synthetic two stroke lubricants, since the esters burn and exhaust even more cleanly than PAO's and the esters provide lubricity in the gas/oil mixtures....

Before the Redline guys have a cow, I should mention their excellent product.
smile.gif
It would be accurate to think of RL as a Polyol-ester/PAO product; containing > 50% PE (RL is very coy as to how much PE is in the basestock blend). The strong point of RL is high temp performance - particularly in a true racing application. However the RL lubes don't provide the cold temp performance, (or extended drain capability) of a very high TBN, PAO based lube like Amsoil or the GC/0w-30 or Mobil 1....

Tooslick
 
quote:

However the RL lubes don't provide the cold temp performance, (or extended drain capability) of a very high TBN, PAO based lube like Amsoil or the GC/0w-30 or Mobil 1....

The percentage of POE RL uses is unknown, but speculated to be 65% or greater. Cost is the main issue why most don't more POE in their oils.

Redline claims 12-18k mile drains with their oils. Most RL oils show a TBN of 10. According to Terry, it's not always the higher TBN that counts, but the reserve it has left over "X" amount of miles. Terry has stated that even at 0, RL has alot of acid fighting reserve left. I wouldn't feel comfortable with having a TBN of 0, but I'm sure it's possible.
 
quote:

Originally posted by TooSlick:
The blended PAO/Ester basestocks have the best overall physical/chemical properties - and the take well to additive packages that are developed for conventional lubricants.

Note that the "Group III" synthetics simply replace the PAO portion of the basestock blend with the less expensive Group III, hydroisomerized oil. So these are more accurately called Group III/Ester blended base stocks.

Pure ester based synthetics more most useful to make synthetic two stroke lubricants, since the esters burn and exhaust even more cleanly than PAO's and the esters provide lubricity in the gas/oil mixtures....

Before the Redline guys have a cow, I should mention their excellent product.
smile.gif
It would be accurate to think of RL as a Polyol-ester/PAO product; containing > 50% PE (RL is very coy as to how much PE is in the basestock blend). The strong point of RL is high temp performance - particularly in a true racing application. However the RL lubes don't provide the cold temp performance, (or extended drain capability) of a very high TBN, PAO based lube like Amsoil or the GC/0w-30 or Mobil 1....

Tooslick


I don't know. 10-18,000 mile OCI's seem pretty darn "extended drain", wouldn't you say. I don't see anyone even attempting these OCI's w/ GC or especially M1 0W-30.
 
UOA is the only way to find out the condition of the oil most people just change it not knowing the conditions. No one OCI is right for everyone. It all depends on the aplication and driving habits. Someday we will have 50k OCI with how oil tech is going it just keeps gettting better.
 
quote:

I don't know. 10-18,000 mile OCI's seem pretty darn "extended drain", wouldn't you say. I don't see anyone even attempting these OCI's w/ GC or especially M1 0W-30.

Ahh, I believe this would be a Redline guy having a cow!
grin.gif
 
quote:

Originally posted by Blue99:
[QB]
.........................PAO....ESTER
Additive solubility......bad....good
VI.......................good...medium
Hydrolitic stability.....good...bad
low/high vis grades......good...medium
cost.....................low....high

Bruce381 is providing us with insights based on his many years as a professional working with lubricant/oil formulations.

I think he is trying to provide a "25 words or less" answer to a complicated question.

BLUE99......YOU are right Thank You I tried to make a short comparison on a lengthy subject.

Unlike PAO's which are defined pretty well esters can be made from a lot of STUFF and the characteristics are all over the place.

VI on esters is from low to high.

Hydrolitic stability varies as to type and raw materials used in the ester, some have great resistance to water.

Bruce
 
quote:

Originally posted by TooSlick:
The blended PAO/Ester basestocks have the best overall physical/chemical properties - and the take well to additive packages that are developed for conventional lubricants.

--snip--

Pure ester based synthetics more most useful to make synthetic two stroke lubricants, since the esters burn and exhaust even more cleanly than PAO's and the esters provide lubricity in the gas/oil mixtures....


Blending PAOs with ester is supposed to help with multiviscosity characteristics.

I can't think of any sane oil blender that would use PAO alone. The poor additive solubility and tendency to shrink seals means that something (usually esters) must be added to swell up the seals. EM does have its alkylated napthalene.

Oh - and Red Line says there's some sort of "synthetic lubricant" in its SI-I fuel system cleaner. I'm guessing it's a POE to help lube the pumps/injectors and provide a level of upper cylinder lubrication.
 
Also dont get to wound up with PAO vs GPIII my feeling is that other than pour point and a slightly lower, VI 140 vs 127 GPIII will last as long as a like vis PAO.
bruce
 
PAO is made from Hydrocarbons, the same stuff dino oil is made from. But it lasts longer and pure PAO is safe for use as a food additive and when used as a drilling fluid doesn't polute the earth. Ester is made from animal and vegetable fats, and is used mainly in aircraft turbine oils and used as a blend agent with PAO to balance the seal swell/shrink problem. Each is equally great when used properly.
 
Okay, I am still "oilly" behind the ears about oil. Basically, I was looking for someone to explain the difference in lay man's terms. Right now I am using Amsoil Euro 5W-40 and from what I have been reading, it is a PAO base stock and very stable, but is there a better oil out there that it's base stock is derived from Esters or do I indeed have a good oil. I just want the best for my baby! I have an 05 VW 1.8T GLI and drive 80% highway 10% city and 10%washing and upkeep!!!! : )
 
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