Replacement/substitute oil for Moto SemiSyn 5w-20?

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Nov 17, 2009
I have been using the following: Motorcraft 5w-20 and a ST3600 or 3614 or the Motorcraft equivilants depending on what is available. Vehicle is a 2009 Jeep Wrangler Unlimited w/3.8 V6. Mileage is currently 73000. I have had two UOA with no anomalies (1st around 6k and the other around 60k). However around the 60k mark, it started using a qt of oil every 3k miles. Noticed the low oil indicating the consumption the day I changed and collected the second sample. Subsequent monitoring indicates that is burning/using the oil around 3k. No smoke or leaks detected/observed. Oil change intervale is 6k per the manual. Typical trek to work is about 48 miles one way 5x a week. I usually get it a WM but it is getting to wear it is hard to find in stock. I then try local auto parts stores with the same issue. Seems to be a very popular oil which speaks for it's quality/popularity. Question I have, is there a good substitute oil for Moto SemiSyn 5w-20 for my application? Just wondering if there is a substitue I can use if I can't get the Motorcraft oil that is reasonably close in mix that I can use that will not hopefully increase the consumption.
For a semi-syn, this should be a nice replacement. I've got a nice stash of this stuff that I picked up when it was on sale with MIR that made it a steal. While I'm not running it anything currently(except snowblower), I've run it in a Ford 4.0L and Dodge 4.7L and it was very smooth. I only ran it 4-5k miles, but should do fine for your 6k OCI considering your hwy miles. Seeing as your in TX it should be pretty easy to get a hold of as well. Also comes in your preferred 5w-20 flavor.
Does Chrysler recommend a 20 weight oil in that engine? Maybe you should try a 30 weight oil. Or a piston soak in case the oil ring is gummed up.
A qt of oil every 3k miles isn't terrible. It's about the threshold of what I'd consider acceptable vs considering it a problem. Obviously, I'd consider looking into the PVC system and any other routine maintenance items that could lead to such consumption. I'm also curious as to why you're using a 20 weight in your situation when a heavier lube may help the burning. Is 5w-20 the factory spec on that engine?
Yes 5w-20 is the recommended viscosity. No other options listed in the manual either. Just like it doesn't have two seperate service intervales either just as the one with 6k OCI.
well I have continued with the 5w-20 and it's consumption has increased just a bit more. I spoke with the folks at the dealership service desk. They think I would have some success going to 10w-30 and even suggested a full synthetic. So I picked up some SuperTech Full Synthetic 10w-30 and a new filter....we shall see what happens
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