Been using full synthetic for years usually with a Wix filter, but sometimes a Mobil 1 or Pure 1 filter. 6000 miles or every six months whichever comes first (usually it's the 6 months with the truck as I average about 8k miles a year, but it's close with my Grand Cherokee which is my daily driver).
It always looks to be in good shape at change time and I've never had a lubrication related problem, so I stick with it...

 

Mobile 1 synthetic 5W20 w/Mopar filter @ 5000k intervals

 

I use a Mopar filter too and set my reminder (iPhone app) @5000k but I change @6000k. This way when my reminder goes off, I can start thinking about when I can fit the oil change into my schedule.

I drive 20k or more miles a year so an oil change every 3k would be crazy! That's when I decided to run Mobile1 and change every 6k.

 

I've been going 18-24 months between changes on Mercedes for over 25 years and three cars with not only no ill effects but also the blessing of Mercedes dealerships and fully warranty protection. We just sold one with 260K miles on it and never had the valve cover off and it was running fine when we sold it. I've read a lot about oils over the years and synthetic oils are superior.

 

Not all 'so called 'synthetics are created equal.Mobil 1 is not a extended drain(over 7500) as are many many others.Most regular dino oil meeting the new specs will all run 5k with no issues.Mobil 1 EP I think? (extended performance) ? cost more and is designed for extended mileage and time.Pennzoil Ultimate is the new over the counter extended drain.Lots of ocd types and boring reading on www.bobistheoilguy.com

 

The ugly secret to oil is that any oil which meets the vehicle manufacturer's specifications and is changed at the manufacturer's recommended intervals will do just fine. If you want to run synthetic, by all means, run it.

I own and ride two Harleys. My touring bike is a stock (other than exhaust, intake, and tuner) 103. That is 9 months old and has 20,000 miles on it. Oil gets changed every 5,000 miles. My bar bike has a built, high compression 103. That bike might see 5,000 miles a year. I run Amsoil 20W-50 in both bikes. Why? Because they're air cooled motors that see a lot of hard use and extreme temperature swings. I've gotten my used oil analyzed by Blackstone Labs, and at 5,000 miles the oil is still within spec and not full of contaminants.

Now granted, the V8 in my truck isn't an air cooled V-Twin, but that's really not the point. The point is that both engines and oils have gotten so good that there's really no reason to worry about oil-related engine failure. If you change the oil in your truck every 6,000 miles with dinosaur juice, you'll be just fine. If you sleep better at night using synthetics (and I count myself as one of those people), then use them.

But as far as your warranty is concerned, stick to the maintenance schedule.

Edited to add- My dealer gave me 2 years of free maintenance with my truck, so I'll be using whatever oil they put in there. That'll be somewhere around 9 or 10 oil changes (given a 6,000 mile interval). Once it's on my dime, I'll switch to Amsoil.

 

That's a good idea.. I change it @ 5k or there abouts so I know when to. Both my truck and car get synthetic mobile one with there respected dealer filters every 5k. Just makes it easier to know when to do it and if I go over by a few 100k, I'm not worried.

 

There are hundreds of opinions on this subject,and many views are right depending on a lot of different things, Like how a person drives his car or what the engine temperature runs.If one lives in the desert and drives HARD. The oil is going to break down faster than someone who lives in North Carolina and drives easy. Common sense can answer most disputes about when to change oil and even what kind to use.
Like I said before When it comes to oil you get what you pay for"Doller General oil
WILL NOT hold up like Castrol GTX"...and will probably give a wax build up."LIKE QUAKERSTATE". The worst oil ever made....
My point is"IF"you use cheep oil and don't mind changing it every 3K,and that makes you sleep good at night.Do it, It's going to be recycled "AGAIN" anyway.
But if your GOOD-oil does good until 6,k miles and you don't feel like your vehicle needs a change.Don't waste your time.Every MAN should know his vehicle,,"Size motor" Heat it's running, Miles per Gallon, Exc....Don't let any-on tell you what your vehicle needs.You should know.Unless your a woman..In that case throw every thing I just said out the window..
But then there are woman out there that know more about cars than Men...
"George"

 

The designated oils that met the specs for the new vehicles like the Hemi and others do not sludge or wax any more.That era is over.QS has not had issues nor Pennzoil products in decades now. In fact are considered top tier oils thse days.Once again read www.bobistheoilguy.com Chryslers 6k or 6 months is with ANY 5w20 meeting the spec thats called for.SJ or SH whatever.I don't know off hand what that spec is.MY 2010 Marquis says up to 7500 on 5w20 meeting specs.

 

My neighbor changes his synthetic every 3K miles. Then I run it for another 6K in my hemi. Wash my filter out with varsol and re-use it.