Vehicle is a 2008 T&C with about 60,000 miles.
I know (?) that synthetic and non-synthetic oils are not generally interchangable and after switching to synthetic I should be consistent in its use. Yes?
I've been using, and did at my last regular oil change about 2,000 miles ago, a quality non-synthetic oil.
Last week I noted that I was down about half a quart and only had Mobil 1 Synthetic on hand. Used that to top off and now (fine time, eh?) wonder if I blundered.
Getting ready to head out on a road trip (roughly 2,000 miles) and wondering if that 1/2 qt. of synthetic may be a problem?
Thanks for taking to time to consider this question.
Rob

 

Non Synthetic that's plain engine oil and not good enough for these engines. Note you don't say whether your Petrol or Diesel. For Diesel engine defo a no no. As too Semi Synthetic well I use it on my 2.5CRD but going full synthetic next time. Full Synthetic, well that's total lubrication. As to a mix of plain oil and Synthetic I would say no way.
Well again lets look at Semi-synthetic. Its a blend of mineral oil and synthetic. So your halfway here. Better protection that mineral oil.
Fully-synthetic. Stable with better protection at higher temps.
Mineral oil. Has its limitations in terms of sludging and manufacturers are having to add synthetic structures to improve it.

 

No, that is a myth, although it may have had some merit in the early days of synthetics.

The synthetic oil you added will be perfectly fine.


From the Mobil website FAQs:
P.S. it is a good idea to specify which engine you have when asking a question, or better yet add your vehicle description to your signature. I had to look though your past post to determine that you are located in the US and have a gasoline (petrol) engine.

 

Not just a merit but a real thing back in the days.

 

HiYa georgef,

So the seller says yes do anything you like so long as you buy our oil !

Can you point me to any Chrysler Technical Service Bulletin that says anything but the opposite for any year and any engine CRD or Petrol and in particular a 2008 bulletin ? Any addition, oil or Cetane additive is a containment to either engine or gearbox oil.

If I was miles from anywhere in an emergency I would add mineral to synthetic [get out of jail card] to limp to safety - on the clear understanding that a complete oil change would then be essential ASP.

 

I have mixed synthetic with plain mineral many times in the past with no adverse effects.
If your engine has a turbocharger, do not use plain mineral. The heat in the turbo from the exhaust at full power will rapidly carbonize it, leading to bearing failure in the turbo.
The turbo can reach 100,000 RPM in some cases. At the very least use synth/mineral blend, but best use full synth. such as Castrol "Edge". There are TWO kinds of what are described as "full synth", hydrocracked and PAO, the PAO being the most expensive. A typical off the the shelf full synth will be hydrocracked. You may have to search for PAO.
Unless you live in a place with big long hills, the turbo is not likely to reach dangerous temperatures. But if you have plain mineral in a turbocharged engine, get it out immediate and replace it.
Synth. oil was invented by the Germans during WW2 for their aircraft.
Leedsman.