Synthetic Oil

[Brucealeg]

I had a small oil question. I keep hearing that once you start using Synthetic oil, that you can't use other oil again.

Is this true, and why? I want to move from the Ford blend to pure Syn.

Bruce

 

[Brucealeg]

Bump. Made a small edit to make the question more clear.

Bruce

 

[MassCobra]

I have heard if you switch back you are more prone to leaks. That is the only thing that I know of.

 

[Brucealeg]

Do you know why? Seems weird that you could drain out all the oil and replace it and that would be bad.

Bruce

 

[CobraBob]

Here are some Myths and Facts direct from the Quaker State website. I only copied these three. There are more. Interesting reading and it answers the questions about switching back to convention oil from synthetic, and about leaks. Here's the link to the Quaker State page if anyone is interested. http://www.quakerstate.com/pages/carcare/whattoknow.asp

Myth #1

* You can't switch from synthetic oil to conventional oil or vice versa.
* You need to start with a synthetic blend for a few oil changes before moving to full synthetic oil.
* Once you start using synthetic motor oil you cannot go back to conventional oil.
* Synthetic and conventional engine oils can't be mixed, or else they react and cause engine problems.

Fact
As long as the synthetic motor oil product and conventional motor oil product meet the viscosity and performance requirements outlined in the vehicle’s owner’s manual, you may interchange them with each other.

Myth #2

* Synthetic oil causes engine leaks.
* Synthetic motor oils eat gasket material and cause engines to leak.
* Synthetic motor oils affect engine seals and result in excessive oil leakage.
* Synthetic oil can’t be used on high-mileage engines.
* Synthetic and synthetic blend motor oils cannot be used in older or high-mileage vehicles.

Fact
Synthetic oils do not cause engine oil leaks. Deteriorated and hardened seals and gasket material cause engine oil leaks. If the seals are already leaking with conventional motor oil, they will leak with synthetic oil. If the seals are in good condition, synthetic oils may be used in high-mileage engines.


Myth #3

* Engines have to be “broken in” before using synthetic oil.
* I need to break in my engine with non-detergent oil.
* If I use regular oil or synthetic oil in a new engine, my engine will take longer to break in.

Fact (This one surprised me!)
It was common years ago for engine manufacturers to recommend non-detergent oils for engine break-in. This was when the pistons used cast-iron “square-faced” rings and the rings needed to wear some to “seat” into the engine. With today’s technology of oils and engine manufacturing, engine manufacturers no longer recommend the use of non-detergent oils for the break-in period. In fact, engines today are factory-filled with high quality API SL performance motor oil, which contains high levels of detergents and dispersant additives.

 

[Brucealeg]

Thanks Bob. That helps a lot. Are you using Synth? If so, what kind? I was thinking of using Mobile 1 5w20.

Bruce

 

[MassCobra]

Originally posted by Brucealeg
Thanks Bob. That helps a lot. Are you using Synth? If so, what kind? I was thinking of using Mobile 1 5w20.

Bruce

Mobil 1 doesn't make it in 5w20, alot of people use the 5w30 including myself.

 

[prttyboyfloyd]

Royal purple 5w30 is what im switching to in a week. They have very good information in the pamphlet to fill you in on the facts and myths of synthetic oil

A synthetic oil can somtime cause leaks but this is only due to bad gaskets. Regular oils actually hide bad gaskets because there thicker and build up over time. when you add a synthetic, it eats away at this build up, making bad gaskets noticible

 

[Brucealeg]

Thanks for all the info everyone.

Bruce

 

[03cobra#116]

I have heard that if you use conventional oil for years and then convert to synthetic that you risk dissolving or dislodging deposits with the synthetic oil that can be harmful if dissolved but that are not harmful left in place.

I wonder if that is a myth or not.

 

[CobraBob]

Originally posted by 03cobra#116
I have heard that if you use conventional oil for years and then convert to synthetic that you risk dissolving or dislodging deposits with the synthetic oil that can be harmful if dissolved but that are not harmful left in place.

I wonder if that is a myth or not.

:??: Read my last post above. ;-)

 

[CobraBob]

Originally posted by Brucealeg
Thanks Bob. That helps a lot. Are you using Synth? If so, what kind? I was thinking of using Mobile 1 5w20.

Bruce

I don't have my Cobra any longer, but I was using Amsoil 5W-30 synthetic and would have switched to Mobil 1 5W-30. It's true that you can't get a Mobil 1 5W-20. IF a manufacturer recommends this weight, use 0W-20. Otherwise use 5W-30.

I use regular Mobil oil in my Infiniti QX4. I might switch to a synthetic at some point but can't justify the price since I change my oil every 3000 miles anyway.