2003 Jeep 4.0, Shell dino 10w-30 SN

[dsr70]

Ran this test to check engine condition more than anything, as I bought this Jeep with 120k on the clock. Have run it to 130k and had 5k on this OCI. Post this test, I'm running high mileage M1. Highest 100C cSt I had in my stash, as I've read the 4.0 prefers heavier grades. Though I've found posts on various Jeep forums saying M1 brings out higher iron UOAs in the 4.0. Regardless, that's a future issue. The high silicon I'm chalking up to the oiled Volant air filter the previous owner had put on. I've been good about oiling (with their oil) and cleaning, and it's still decently oiled at the moment. I had read about general complaints that oiled filters don't filter well and it seems to hold true in my case. I wheel offroad in summer dusty CO mtn environs. But no more, I'm replacing it with a cone shaped AEM Dryflow element, in the Volant air box. I do not have the stock box setup to put back in. I'm hoping the elevated iron and aluminum are directly from the poor filtration/high Si. No anti-freeze or water, and trace fuel, looks good. No oil burn in the 5k. Which is incredible, unless I forgot and didn't note some add along the way. Anyone's thoughts are welcome. Thanks.

 

[Chris142]

Ya the iron and silicone are way up there. I recomend that you find a stock air filter on Craigslist or eBay.

 

[Donald]

Go back to a stock air filter and housing. These oiled air filters give you about 0.00000001 % more HP but are poor are providing good filtration. Thus more dirt into the engine. You may need to do a short OCI (or two) to get all the dirt out of the engine. Check the whole air intake and PCV, etc. Grommet for PCV not hardened. Don't assume 100% of the cause of high silicon is the oiled air filter.

 

[addyguy]

Looks horrible. Change the air filter to a better unit, and do some short (3k) runs with a 40-weight (HDEO 15W-40 would be great) to clean out the grit in the engine.

 

[Lyman]

Put the stock air box back on! You should easily be able to find one.

 

[Popsy]

Tin at 5 ? That's sometimes a sign of overheated oil, but in this case I'm unsure.

 

[StevieC]

Yowsers that's a lot of iron for such a short run Go back to the stock air filter. I bet the Iron and Si are related. I'd also maybe dump the oil early in the next 2 oil changes after you change the air setup to help flush out the Si and Iron from the crankcase. Just use an economy oil for this. No need for anything expensive.

 

[bullwinkle]

It's a 4.0, they'll run for forever (unless they have an 0331 head & it cracks)! I would run short OCIs of an HDEO, and I wouldn't be afraid of 15W40 in summer heat-it is an old school AMC design, after all.

 

[Donald]

Originally Posted by bullwinkle

It's a 4.0, they'll run for forever (unless they have an 0331 head & it cracks)! I would run short OCIs of an HDEO, and I wouldn't be afraid of 15W40 in summer heat-it is an old school AMC design, after all.

Cracked piston skirts are another issue that can grenade these 4.0 engines.

 

[dave1251]

Flashpoint really dropped throw in a bottle of Techron or Regane.