JK Synthetic Oil Change Interval

So our local dealership is only open on weekdays from like 10-2 or something f'ing ridiculous, so we've officially make the transition to doing our own oil changes and keeping the receipts on the JK.

I'm not sure what the dealership was putting it, but I'm starting it on Mobile1 synthetic 5w20.

My questions is, I've never had a modern vehicle and especially not one with synthetic. What do you other JK guys recommend as an oil change interval?

I do 3k -4k with the YJ, but it's conventional and an older engine that only takes like 4 quarts. I've been told that 5K -8K is pretty ok with the JKs, especially with synthetic and the freaking 6 quarts of oil it guzzles.

What is everybody else doing?

What does your owners manual recommend for oil change intervals?
The longer you leave it in there the dirtier the oil seems to get by the time you change it again.
Even if you use synthetic.
The oil filter can only keep the oil so clean, don't forget to Add that into the equation

Markmmaark wrote:What does your owners manual recommend for oil change intervals?
The longer you leave it in there the dirtier the oil seems to get by the time you change it again.
Even if you use synthetic.
The oil filter can only keep the oil so clean, don't forget to Add that into the equation

New member here with a 2000 Cherokee.. with 20k miles on new motor...I run 5w-20 full synthetic and the guy who does a lot of work on my other jeep and is a great mechanic and oversees a bunch of shops in NE tells me 5,000 miles is a good interval vs the 3,000 for conventional. I also run K&N filters.... my .02

John

5w 20.. are you going for gas mileage or are you in Alaska.
Doesn't it require 10-30 ? The manufacturer kinda knows what to use, they have been making 4.0s for some time now with good results in the longevity department using 10-30.
Just saying...
Got a couple tjs here running 10-30 one has a jasper engine in it with 100k on engine and is doing ok.
Been running the recommended 5w 30 in my 4.3 S10 blazer and It has 435 k on it and it has never ever been apart..EVER
Personally I would go with the manufactures recommended weight motor oil.
Just my 2 centavos.

Well my bad.... it had 5W-30 in it previously but when I had my daughter take it on her day off to have it changed they put in 10W-30.... so there it is....

ha ha, no problem. (Welcome to the site, btw!)

Yeah, the oil viscosity ratings used to confuse the heck out of me and I would panic if I accidentally mixed 5w30 with 10w30 thinking I was going to blow my engine up, etc.

When I finally did the research and learned what all the numbers meant, I realized I was way overthinking things, ha ha.

Well there is no over thinking here,,
The 4.0 engine is not an aluminum rev monster like a close tolerance lexus engine.
It is a glorified fuel injected sloppy old style lifter clacking at start up amc pacer / gremlin engine.
No dissimilar metals like an aluminum head / cast block , with different heat dissipation properties.
4.0 Engine gets up to operating temp and like magic the oil pressure goes down HMMM.