Synthetic oil bad for break-in?

[akhristov]

I know the reasoning to why synthetic oil prevents an engine to be properly broken in, but...

Don't most car manufacturers these days use synthetic oil as a factory fill?

The reason I'm asking is because I want to replace the bearings in my engine and use Red Line from the start. They do put "not to be used for break-in" on their bottle, but how important is that these days?

 

[SERonBLAST]

I am not for sure, but i do know you must go lightly and give the ring time to seat properly. Dont overdue it, be gentle and use what is recommended.

 

[crazyoildude]

when we rebuild an engine we put in what the engine is supposed to have
Most engines we use conventional but some like the vettes, Mercedes audi and a few others we use synthetic...Today there is not so much difference between a store synthetic and a good conventional oil...Use what you want it will break in fine with most,,

 

[Brons2]

Originally Posted By: akhristov
I know the reasoning to why synthetic oil prevents an engine to be properly broken in, but...

Don't most car manufacturers these days use synthetic oil as a factory fill?

The reason I'm asking is because I want to replace the bearings in my engine and use Red Line from the start. They do put "not to be used for break-in" on their bottle, but how important is that these days?


If you're only going to be replacing the bearings and not the rings, then there's no reason not to run synthetic.

 

[akhristov]

Originally Posted By: Brons2
If you're only going to be replacing the bearings and not the rings, then there's no reason not to run synthetic.


I will be replacing the rings as well. I know VW recommends synthetic oil for the engine though, so I guess break-in shouldn't be a problem?

 

[dwendt44]

The engines that come with synthetic are run for more than a few seconds like the run of the mill motors are.
Some, like Porsche, M-B, and BMW do some extensive (relatively) testing of each engine before installing in the chassis.
In my case, the 'free' oil change at 600 miles was done with Mobil 1 (accidentally). I think it slowed break-in somewhat.

 

[dnewton3]

No, most cars sold in North America don't use Full Synthetic as factory fill. It is used in some notable models ('Vette, Porche, etc) but the VAST majority of cars come with dino. It's a cost consideration.

Ford might be the exception? I'm not sure if they use conventional or semi synthetic-syn as FF. I would think it would be dino as well. The only reason I question this is because the MotorCraft semi is so well known.

 

[akhristov]

I think (but I'm not too sure) the factory fill for the engine I'm talking about--the Audi/Volkswagen 1.8T--was GC.

 

[typ901]

I get the factory fill for various autos is synthetic, Porsche, Corvette with M1 etc. Does this also mean that the engine is broken in from the factory with synthetic? Do they break them in with dyno, and then dump it out and fill with synthetic?

 

[Wilhelm_D]

Originally Posted By: typ901
I get the factory fill for various autos is synthetic, Porsche, Corvette with M1 etc. Does this also mean that the engine is broken in from the factory with synthetic? Do they break them in with dyno, and then dump it out and fill with synthetic?


"Break-in" is pretty much a thing of the past with most modern engines.

The manufacturing processes and materials result in surfaces that don't need the long gradual careful wear-in needed 30 or 40 years ago.

 

[andrewg]

I would go with using a dino for about 500 miles....then go to a high quality synthetic. I would tend to regard the advice of Red Line to be credible.

 

[addyguy]

Originally Posted By: akhristov
I think (but I'm not too sure) the factory fill for the engine I'm talking about--the Audi/Volkswagen 1.8T--was GC.


It isn't GC, but it's something similar - an A3-rated 30-weight.

There have been a few used oil analysis of FF's on the new 2.0T engine, that shows roughly what this oil is....

 

[Loobed]

Originally Posted By: akhristov


The reason I'm asking is because I want to replace the bearings in my engine and use Red Line from the start.


Bearing do not require "break-in."

Piston rings, and cam and lifters go through a seating process commonly referred to as break-in.

One reason not to use synthetic oil for a new motor break-in is the cost. When we rebuilt motors, we would run them for 1 hour at fast idle and then change oil and filter. It would be a waste to run synthetic oil for only 1 hour.

 

[Patman]

It's a myth that synthetic oil is "more slippery" than conventional oil and won't allow an engine to break in properly. I'm surprised anyone on here would think that synthetic oil is more slippery, considering all the used oil analysis we've seen which clearly show that engine wear numbers with the same engine using synthetic vs conventional do not show any different numbers between the two. Synthetic oil can go longer intervals, and will flow better in the extreme cold and protect better at high oil temps, however it is not "more slippery".

 

[SteveSRT8]

yeah, the whole question has been beat to death on here.

Too many cars, including mine, ship with synthetic now to say it is not suitable for break in.

And the whole "break-in" process is a myth anymore.

The rotating assembly is either right or wrong, and the rings are seated in literally seconds.

Old school hangover.

 

[aquariuscsm]

From what I understand about synthetic vs dino,synthetic doesn`t lubricate any better,it just runs "cleaner",and since it`s a "cleaner" oil,it can go longer in an engine,right?

 

[Zedhed]

Urban myth -- many new cars come with Mobil 1 as factory fill, like Porsche and Corvette.

Don't believe those "old farts" who think oil is still rated SF

 

[yannis]

by Richard Huggins an ex-formula 1 chemist:

"
The viscosity of the oil between synthetics and minerals is not an issue and has nothing to do with why they are better - viscosity is viscosity regardless of whats in question. It's all related to the molecular composition of the two basestocks, where synthetics are "harder" and cause the glazing effect with new metals because they haven't keyed in. The way they key in is from thermo adjustament, and synthetics cause a more rapid transfer. Minerals are "softer" and are more forgiving with the metals and allow for a more raw type of lubrication, where as synthetics tend to run more clean which is not exactly what is needed for new engines. Porsche use different metal components for their engines like and these metals dont suffer from the same problems that traditional compositions do. "

 

[yannis]

and this,from here:
https://bobistheoilguy.com/forums/posts/63138/
"
Thin oils can cause a “glazing effect” in the cylinders of pushrod type motors and those that also rev relatively slow. Although the glazing effect is strongly dependent on the metal composition of the cylinder an the type of oil that is being used. Glazing is where the cylinder has effectively gone ultra hard and just like super heated metal, it gets a pearly glazed appearance on inspection. Once this glazing has occurred, then oil consumption will increase as will emissions of white smoke and the compression and hence power will decrease. This is a problem often seen with 80’s –mid 90’s Mitsubishi engines. What causes the glazing?? Well, the glazing effect is caused by the premature oxidation of light HC chain molecules and the hardening of the metal surface of the cylinder wall. "

 

[Popinski]

Originally Posted By: aquariuscsm
From what I understand about synthetic vs dino,synthetic doesn`t lubricate any better,it just runs "cleaner",and since it`s a "cleaner" oil,it can go longer in an engine,right?


Then why does my engine run smoother and quieter with Synthetic?