I bought my 2007 jku used with 34000 miles. The original owner let the dealer change the oil every 3000 miles and that is what I have continued to do. It now has 47000 miles and I am debating to change to oil to Mobil 1 synthetic. Will this be ok being almost 50000 miles into the motor? If so what interval should I change it?

Thanks

 

Well i just bought a 2008 and the previous owner worked and the dealership, so all oil changes were done there. I changed to synthetic oil when i bought because I know its better. I change mine at 5k. But its up to you.

 

There is no harm in switching back and forth as often as you like.

 

i would go for it...i've read heaps on the subject...
on forums and all over the 'net 'till i got a sore head...
and everyone recommends it...

i change every 5000 with an extra filter change in the middle...
my JK doesn't get heavy use...the dealer told me every 7500...
but i want top oil [mobil 1]...and clean oil in my motor.

 

I bought my JK with 28,000 miles on it ans immediately changes to Castrol Syntec, (now Edge) synthetic motor oil. I have run it on other rigs for years and they still run like new. I will run nothing else. Mobil 1 while being so popular isn't near the top of the Synthetic test comparisons list by the way. Amsoil is. But I don't have an outlet near me.

 

With so many great oils out there, and all the different ways of measuring which one is best, it doesn't matter which one is used. Each manufacturer's tests are tailored to their own product. I've used the same brand since the '70s, and see no reason to change.

It's regular checking and changing of the oil and filter that makes the most difference.

 

No matter what other wonderous properties people claim for synthetic oils, the main difference between them and pure mineral (dino) oils is that they don't break down as fast and thus you don't need to change them as often. So if you religously change your oil every 3k miles/3 months on the dot then regular non-synthetic is fine and cost effective. If you extend your changes out to 6K miles or over then full-synthetic will offer better protection, particularly under harsh colditions (many short, low-speed trips in cold weather or sustained high operating temperatures and RPMs).

 

All correct.

But the main advantage (in my mind) is that synthetics have much better flow properties at start-up in cold weather.

OP, check out Motor Oil 101
www.bobistheoilguy.com/cms/

 

Sounds like the original owner had it serviced regularly.
I would use synthetic oil and change it on a 3,000 mile interval, that is what I do.
Other than cost, there is no reason not to use synthetic; however, cost is debatable if the motor lasts longer before needing major repair.

 

I bought mine from the dealership and changed the oil to synthetic the very next day. Synthetic is better for the motor and you can run longer in between oil changes if you want. I usually do it every 3k still though. Takes me 6 months to put 3k on it though.