Synthetic vs. Dino. By a Mechanic.

[Copperhead]

I have had great results with Amsoil synthetic in my Jeep Liberty Diesel. My Cummins ISX hated the stuff. Could not get steady wear numbers using it. When I put the ISX on Mystik Jt-8 synblend, it really settled down and gave good numbers. My current Detroit Diesel is giving great numbers with Delo synthetic and has also gotten similar numbers with standard Delo. This similarity in analysis numbers is why I will use the synthetic Delo in the winter to offset extremes in cold starts (plus I can get it at $19.98 a gallon at my local Wally World), and I use the conventional Delo oil in the summer months. My CUT is showing good results with Schaeffer. I use Mobil synthetics in the gearbox and diffs on the semi. On my previous semi, I used a top notch synthetic in drivetrain that was a local distributor brand label. I just can't seem to find a one size, fits all brand of oil that turns in great results in every piece of equipment I own. Never have.

For my semi, oil changes are never done below 30,000 miles. CUT gets an oil change each Fall. The Jeep goes 10,000 between oil changes. I have taken one semi to 1.4 million miles, doing 30,000 mile oil changes using Kendall conventional 15w40, and never had to open up the engine for a major repair. Took my last semi to almost 1 mil doing the same thing with Mystik synblend oil before I sold it. Still did not have to open it up for a major engine repair. The 2013 semi I have now, too new to see how it does. It only has 72,000 miles on it so far. Out of all the trucks I have owned or driven in over 3 decades in trucking, only have lost 1 turbo in all that time. So, I have had good/bad results with synthetics and the same with conventional oils. Brand loyalty means nothing to me. I long since quit falling for that marketing game. The Jeep now has 104,000 on it, and the UOA's look as good as when the engine had 20,000 on it.

 

[jeepmanjr]

Before I retired we had 120 vehicles in our fleet. We switched to syn oil a couple of years back for increased change intervals. Anyway, in 26 years of hard use/abuse and some vehicles with fairly high mileage, I can only recall one catastrophic failure and I don't know if that was oil related. Heavy off road use, very long periods of idling in 110 degree plus temps, high-speed runs, you get the picture. Back in the day they made us use recycled dino oil and still no oil issues to my knowledge. Me? I use synthetics in everything I own, including my tractor and lawn mower. I even use Mobile 1 synthetic grease. I'm a big fan of Mobile 1 products.

 

[PapaPerk]

Before I retired we had 120 vehicles in our fleet. We switched to syn oil a couple of years back for increased change intervals. Anyway, in 26 years of hard use/abuse and some vehicles with fairly high mileage, I can only recall one catastrophic failure and I don't know if that was oil related. Heavy off road use, very long periods of idling in 110 degree plus temps, high-speed runs, you get the picture. Back in the day they made us use recycled dino oil and still no oil issues to my knowledge. Me? I use synthetics in everything I own, including my tractor and lawn mower. I even use Mobile 1 synthetic grease. I'm a big fan of Mobile 1 products.

But your own data from 120 vehicles says that Dino oil is fine.

 

[jeepmanjr]

But your own data from 120 vehicles says that Dino oil is fine.

Yes sir, that was the point. Oil and filters were changed religiously every 3K miles. Personally, I think that is the key to longevity. I'm sure all my vehicles would be fine on dino oil as well, but I sleep better at night when I use syn products. Just one of them things! ;-)

 

[sw03]

The posted statement I made about the OEM extending the warranty is true. Just check with Eaton corp and Meritor corp regarding their transmission and drive axles on commercial trucks. They will extend the warranty from 500,000 miles to 750,000 miles if owner uses synthetics in them. I never stated in any way something like this regarding engines. Here is some published data sw03 for you since you requested it. I'll let you dig up something from Eaton corp to try and prove me wrong. Good luck.

Eaton Roadranger warranty guide....See page 8 note 3 on line haul truck warranty.
http://www.eaton.com/ecm/groups/public/@pub/@eaton/@roadranger/documents/content/ct_126924.pdf

I never said it was not. Trans and drive axles are a diff story outside of engine oils. All I am saying is I have been here since 02 and thousands of posts (not this logon) and most issues are nothing new. And will this pdf hole up when an engine goes south? Problem is this is commerical trucks and it does not apply to most one here. And define synthetic here. Hence why I lost faith in forums.

 

[crashz]

For me, synthetic is better at cold starts. Normally not a big deal, but in all weather I can hear a minute difference at start up. Does it make a difference? No idea. But for those few seconds, my engine runs smoother and the oil gauge comes up to normal pressure a millisecond sooner, and that is worth the difference to me.

I put all brands of Dino and Syn in my last truck and found that all performed admirably in the GM LS engines. But some do better at start, which typically is a 0W-30 and therefore a synthetic.

 

[grainger12002]

synthetic for this cold weather dweller.

Preston..

From CT

 

[speedyspider2050]

Hello Grainger... Yes it is beyond cold where u r right now.... Synthetic is just what I to prefer... Hope ur keeping warm... Take care...Preston

 

[Copperhead]

That is an application where synthetics come into their own.... down right nasty cold. There can be hardly any dispute that synthetic offer cold weather starting performance over conventional oils by quite a margin. For those that have that problem, no doubt that synthetics are a wise choice.

sw03, it is true that commercial heavy vehicles are not what everyone here deals with, but they are a solid proving ground for seeing how different things work. Especially synthetics vs conventional oils. Maybe these types of vehicles are not used by the majority here, neither does the majority put their vehicles thru quite the demands that commercial heavy vehicles go thru. Seeing how synthetics compare to conventional oils when a diesel engine is putting down over 500 hp and over 1800 lb of torque and doing it on flat ground and mountain sides, with over 22 tons of freight on board a truck that already weighs in at a 16 tons by itself. If there can be shown no clear advantage one way or the other in this environment, it can be reliable data to inform. And if the OEM's of equipment in this type of situation would extend a warranty 50% based on using synthetics in their drive train components, then there must be something to that also.

Not too many folks here run regular oil sampling to see how oils are actually doing like commercial users typically do either. But when those that do can do extensive sampling and show, in most engine applications, that there was no appreciable difference between conventional and synthetic oil sampling results, including wear numbers and fuel economy, that is data also. Most folks, just about everywhere, will base their opinions on nothing more than brand loyalty and justifying spending a certain amount of money. Most folks do no want to think they might be making an error in judgement. Those of us in the commercial side of things do not usually have such egos to bruise. We are more concerned with how the cost performance ratios play out. And, with the exception of certain applications and conditions, synthetics in engines cannot be justified by most folks. But they have their place and are the best choice in some applications. Synthetic make a lot of sense in components other than engines. For engines, only special applications, serious extended drain intervals using bypass filtration, and extreme cold conditions can truly justify synthetics in engines, unless the OEM specifically recommends them.

And I can sense by your comment "define synthetic" you have fallen for the "true" synthetic marketing ploy. Most would think that a "true" synthetic is a Group IV base oil and that a Group III base oil is not a "true" synthetic, though they are both marketed as such. Let's look at this. BOTH groups are made from carbon based sources. Group III from mineral oil and Group IV from natural gas. Based on refining techniques, both are technically "synthetic". There is no oil that is made from nothing! And the nasty truth for those that swear by the "true synthetic" myth, is that even the Group IV oils that claim to be "true" synthetics also have Group III synthetics mixed in with them at the user level. That is because Group IV will not hold the additive package in suspension properly, so a percentage (usually 25%) of Group III is added to the mix. Schaeffer oil is honest and up front in acknowledging this in their data sheet on their 9000 full synthetic, compared to other "boutique" brands of oil. And the performance differences between Group IV and Group III are only detectable in a controlled lab testing scenario. No one out here in the real world is going to be able to tell the difference. In the past, yes, but not in today's oil refining climate. The technology of refining Group III has gotten that group of synthetic so close to the performance of group IV that it is only in the realm of the arcane that differences are detectable.