3-5K synthetic oil vs. new conventional oil

[Bill in Utah]

I've been in one hundred and teens for many days with conventional oils. Even with yesterdays oils and never a problem.

Here it stays in the 90s for months and gets quite cold. Again never a problem for decades.

My point is the majority of the vehicles out there (like 9+ out of 10) run normal oils, most go past what the recommended OCI from the factory and still rack on the miles.

How are they doing that? And please don't say that their vehicle run like [censored] towards the end of the life of the vehicle and syn users don't because you really don't have any data to support it. (this statement is for anyone else who wants to jump in and post something without facts)

The big thing in engine life is to use the correct oil (the mfg really does know something) for the correct OCI.

Changing oil is a good thing! Not at 2k either.

Take care, Bill

 

[jstutz]

why would hot weather, even if its 130F outside, be hard on oil at all. The stuff is run at 185 - 200 F all the time and regulated to stop at those temps. Or is it an issue of the cooling system being inadequite at those temps?

 

[mechanicx]

Originally Posted By: jstutz
why would hot weather, even if its 130F outside, be hard on oil at all. The stuff is run at 185 - 200 F all the time and regulated to stop at those temps. Or is it an issue of the cooling system being inadequite at those temps?


I guess sometimes even with a fully functioning cooling system when the temperature gets much over 90, with the A/C on and in stop and go driving or high speed driving it's not too uncommon for the coolant to get into the 220-230 range. You got to figure the oil is somewhat hotter than that. I always assumed the average oil temperature to be at least 20-30 degrees higher than coolant temp, but I guess that depends and that's not really putting dino over the limit anyway.

 

[Audi Junkie]

Originally Posted By: gfh77665
The degradation is less with Syn due to more stable and homogenous molecular structure.



Can you quantify that somehow?



fwiw, Delo's TBN is pretty high.

There are actually very few UOAs here that dino oil would not have preformed adequately. otoh, I see synth UOAs as low as 2k miles.

 

[gfh77665]

Originally Posted By: jstutz
why would hot weather, even if its 130F outside, be hard on oil at all. The stuff is run at 185 - 200 F all the time and regulated to stop at those temps. Or is it an issue of the cooling system being inadequite at those temps?


The pan on my Honda is just 4.5 in. above ther pavement. Even if the engines off, radient heat just cooks things. It only adds to the issue if you are driving through a city. "Urban heat islands" the meterologists call then. My kids sometime complain that their feet get hot even in shoes during the summer. Over time, heat does degrage oil. Syn has better resiliency to the heat.

 

[gfh77665]

Originally Posted By: Audi Junkie
Originally Posted By: gfh77665
The degradation is less with Syn due to more stable and homogenous molecular structure.


Can you quantify that somehow?


Quantify? Just look up the top end of temp range for various brands. Keep in mind turbos widely recommend syn. That speaks volumns...

 

[Bill in Utah]

Originally Posted By: gfh77665
Originally Posted By: jstutz
why would hot weather, even if its 130F outside, be hard on oil at all. The stuff is run at 185 - 200 F all the time and regulated to stop at those temps. Or is it an issue of the cooling system being inadequite at those temps?


The pan on my Honda is just 4.5 in. above ther pavement. Even if the engines off, radient heat just cooks things. It only adds to the issue if you are driving through a city. "Urban heat islands" the meterologists call then. My kids sometime complain that their feet get hot even in shoes during the summer. Over time, heat does degrage oil. Syn has better resiliency to the heat.


But ANY radiant heat is a LOT less than any oil temp that your oil will be.

Your kids feet are around 98-99F degrees. The oil in your engine will be close to twice that much.

Bill

 

[Bill in Utah]

Originally Posted By: gfh77665
Originally Posted By: Audi Junkie
Originally Posted By: gfh77665
The degradation is less with Syn due to more stable and homogenous molecular structure.


Can you quantify that somehow?


Quantify? Just look up the top end of temp range for various brands. Keep in mind turbos widely recommend syn. That speaks volumns...


And MOST mfg of engines with turbos don't REQUIRE syn oil to be used.

Bill

PS: And I've said here for YEARS that if it was me, anything force fed I would run syn. But the MFG don't agree with me.