duneslider

I hadn't put two and two together but I have not noticed spark knock since switching to 10w30 mobil 1. I haven't noticed any ticking either, still seemed to burn a little oil after a long road trip but not as much as when running 5w20.

Which brings me to what makes me curious with this engine. If you have seen my other posts, I am replacing my engine very soon. I have almost 60k miles and have what I feel is excessive oil consumption, had ticking, spark knock, and most recently leaking head gaskets. I have gotten a new engine (8 miles on engine when pulled from 2011 JK) and will be putting that in. Been contemplating what oil to run.

I wonder how much oil type and weight has contributed to my engine issues? I have run mobil 1 5w20 since breakin until the last 3-4 thousand miles, when I put 10w30 in, changing oil about every 3500 miles.

Wonder what I should do with the new engine? I am thinking that I will for sure run 5w30 Dino this time around and am considering having oil analysis done a few times after breakin. At that point I might switch to 10w30 Dino for a couple oil changes and have another analysis done to see how it compares.

Really wondering if Synthetic is worth the money, or if I am better off just changing oil every 3k?

My experience so far is the only NEW vehicle I have bought I also ran synthetic in and the engine is gone at 60k. My truck has 140K, has only had irregular oil changes (3-5K) with cheap dino and has never had an issue and runs strong! My old jeep, regular dino 3-4k, 150K+ never and issue. My old car, regular dino, 110K no issues. Obviously, too small a group to say synthetic is the cause but enough group to say an engine maintained on regular dino will run a long time.

Ryan0260

I don't know why chrysler recommends the 5w20 over the tried and proven 10w30. My friend is the service manager at the chrysler dealership and said the same thing. He said all they stock for their oil is 5w20 and said I should should switch as I have the pinging and consumption issues myself. If I was to get a new motor I would run 5w20 or 5w30 dino myself. I have heard of synthetic causing consumption issues and detonation problems on other vehicles. Not sure if it is from the synthetic oil itself or because people change the oil less frequently...

duneslider

I think I am going to go at least 5w30 dino and see what it runs like and do an analysis or two. And then decide from there.

helicopter78

use the recomended oil

Dad

Yes. See my post #39 in this thread. With the 5W oils my 3.8 was consuming about 1 quart every 2200 miles. Switching to Castrol GTX 10W30 consumption is negligible, barely a quart every 6000 miles. The oil level starts near the top of the hatch marks when I change the oil and by the time I change the oil again 6000 miles later it's nearing the bottom of the hatch marks.

They can't. 5W20 is required to meet their EPA fuel economy demands.

jktoy

I switched to 10w/30. And now I use no oil and have not had any knocking.

Ryan0260

How much oil were you using before the switch to 10w30?

jktoy

I would use anywhere from a half to a quart every 2000 miles or so. But the biggest difference to me is the sound of the engine. It just sounds smoother. And I don't have ruff starts or knocking.

BlueLespaul2006

I ran 5W-30 for a while for oil consumption. Right now im running 10W-30 and its running like new.

Yankee

We were discussing this oil viscosity issue a while back at the local dealer, where they have a pretty decent service floor. I had the service manager and a mechanic I trust tell me only days before a Mopar replacement engine came in with a tag to use 10W30, even though the original engine came from the factory with 5W20.

Despite what Chrysler might say, they told me they had no problem with anyone running 10W30 in the 3.8.