97 Jeep 2.5L 3000 miles on Rotella 10w-30

[JohnnyO]

97 Jeep TJ 4-banger, 156,000 miles on motor. As I have told people on the Jeep boards, Rotella is an excellent oil for them because they tend to throw off a lot of iron. The previous UOA was plain Pennzoil 5w-30 since it was winter and the second Auto-RX rinse cycle. Then too, the engine holds 4 quarts and over 3000 miles I added...4 quarts...so any oil might show up well. I cannot explain the higher oil consumption with Rotella. It is my daughter's Jeep, she is a college student and does not put on a lot of miles. http://72.35.72.219/~library/15563/Jeep_UOA_11_2011.pdf

 

[JohnnyO]

Right now I have Max Life 10w-30 in it, hopefully oil consumption will be less, will get another UOA, and go with which oil it likes better,

 

[gomes512]

Looks alright for the inline, my 4.0 sheds similar amount of iron. Noticed that the HDEO's on average trend less iron like you noted. Wait, did I read right? You added 4quarts makeup? Is that actual burn off or is it leaking? Is the ccv/pcv working alright? Mine has a tendency to clog up easily since the orifices are so small.

 

[JohnnyO]

Originally Posted By: gomes512

Wait, did I read right? You added 4quarts makeup?

Yup.

Quote:

Is that actual burn off or is it leaking?

It isn't leaking. It isn't smoking either. Best guess I got is that the Rotella got the 156k ring packs so clean that oil is getting by. Head was rebuilt before I got it and compression is a solid 175-180 in all four cylinders. I will check the PCV, thanks for the heads-up.

 

[440Magnum]

Originally Posted By: JohnnyO

Originally Posted By: gomes512

Wait, did I read right? You added 4quarts makeup?

Yup.

Quote:

Is that actual burn off or is it leaking?

It isn't leaking. It isn't smoking either. Best guess I got is that the Rotella got the 156k ring packs so clean that oil is getting by. Head was rebuilt before I got it and compression is a solid 175-180 in all four cylinders. I will check the PCV, thanks for the heads-up.

156k is LOW mileage for a Jeep 2.5 or 4.0. My daughter's 4.0 (the 99 in my sig) has right at 150k and gets zero makeup oil in a 6000 mile change interval on RT6 5w40. If that 2.5 is burning that much oil its either been damaged sometime in its past, or there's another problem there somewhere. I suppose that partially-coked or stuck rings might explain the problem, but I do not believe "cleaned" rings would explain it. Even if they're worn, getting them clean and un-stuck will LOWER consumption.

 

[JohnnyO]

Originally Posted By: 440Magnum

156k is LOW mileage for a Jeep 2.5 or 4.0. My daughter's 4.0 (the 99 in my sig) has right at 150k and gets zero makeup oil in a 6000 mile change interval on RT6 5w40.

You know your Jeeps. LOL. They're not even broken in until they hit 100k. In ours the tranny (automatic) is getting some slop but it runs great.

 

[addyguy]

Silicon is fairly high for only 3k, and insols are high on the PYB run. I'd say 'junk' is still rincing out from the A-X run, and there may be some abrasive wear from it.

 

[KCJeep]

Were your 4 qt's make up also Rotella? I see the Pennzoil sheared out of grade, and the Rotella sheared some too... zikes.

 

[JohnnyO]

Originally Posted By: KCJeep

Were your 4 qt's make up also Rotella? I see the Pennzoil sheared out of grade, and the Rotella sheared some too... zikes.

Yes. I bought another gallon jug and used almost all of it. This Jeep does have a 3 speed automatic, no OD, and as near as I can tell 4.11 gears, so it spends a good deal of time at 2500+ rpm.

 

[84zmyfavorite]

Those gears would be either 3.73 or 4.10 with the 2.5 four cylinder and the Chrysler 904 3 speed auto. Those 2.5s are every bit a durable as the 4.0 Inline 6. The 4.0 is based off the 258 Inline 6 and the "Hurricane" 2.5 four. Ive got the 2.5 in my 84 manual tranns Cherokee, and four Cherokees with the 4.0 Inline 6. Ive also got the GM 2.8V6 in my other 84 Cherokee with the same 3 speed auto you have behind it. Durable 3 speed and durable 4 banger.