2000 Cherokee 4.0 136k miles; Rotella T5 10w-30 3k mi

[REC]

Here is my oil sample just got back. The Cherokee hardly gets driven so it sits lot. I'm using Rotella T5 10w30 although this time had to top off with some T6 15w40 (about 1/2 quart if that much...yes its a Jeep so it leaks some). Sample was taken at a 3k interval as I'm trying to get a baseline of the condition of it and how often I need to change. The Jeep was bout used with 113k miles on it and I don't know the condition of the motor or how it was kept up. One thing I was worried about was coolant in oil as it has the 0331 heads but have not been seeing any coolant lose now since replaced the water pump.

 

[JLTD]

Looks fine...with the 5.75 TBN you can probably go 7500 miles.

The 4.0 throws a lot of iron, so 10ppm at 3,000 miles is good - my last 4.0 had about 60ppm at 10,000 miles.

 

[Chris142]

Check the oil pan bolts on the driver's side where it's right next to the pre cat's. That's where they usually leak from and tightening those bolts usually stops that leak.

 

[REC]

Strange thing is the 2000 came out with the 0331 heads which is known to crack. I don't know the history of this vehicle. Motor has somewhat low oil pressure was 8psi hot idle but 50 psi driving (verified with mechanical gauge) and is little noisy on bottom side but have not had time to verify its from the lower end of motor. Right now running T6 15w40 on this oil change just to see how it does and will go a little longer for next oil change.

 

[REC]

Originally Posted by JLTD
Looks fine...with the 5.75 TBN you can probably go 7500 miles.

The 4.0 throws a lot of iron, so 10ppm at 3,000 miles is good - my last 4.0 had about 60ppm at 10,000 miles.


Thanks for the words of encouragement on the TBN. I have been doing some google research on just what everything is on the report and where it might of came from.

 

[REC]

Originally Posted by Chris142
Check the oil pan bolts on the driver's side where it's right next to the pre cat's. That's where they usually leak from and tightening those bolts usually stops that leak.


Wanting to remove the oil pan as I know the RMS is leaking some but going to be another project next year as I just welded in new floor pans, rebuilt the entire front end and replaced the brake system on it.

 

[53' Stude]

Rec: looks ok considering. Thanks for the UOA.

May I ask what oil filter you use? Thank You

 

[REC]

FL400s filter

 

[REC]

Well crap just realize this test does not check for coolant but I guess since it checks for water its still good?

 

[benjy]

my aunts 99 cherokee sport is great except the typical RMS leak, 9x,xxx miles 10-30 supertex + wix filter every 6 months as it only get short trips 1 to 2 thou every change. faded paint good interior + wherever she parks theres someone looking to buy it, engine is quiet as a church mouse!!!

 

[REC]

Originally Posted by benjy
my aunts 99 cherokee sport is great except the typical RMS leak, 9x,xxx miles 10-30 supertex + wix filter every 6 months as it only get short trips 1 to 2 thou every change. faded paint good interior + wherever she parks theres someone looking to buy it, engine is quiet as a church mouse!!!


Sounds like a keeper!

 

[Chris142]

Not every 0331 head cracks. Odds are that if it has not cracked yet it's not going to.

 

[REC]

Originally Posted by Chris142
Not every 0331 head cracks. Odds are that if it has not cracked yet it's not going to.


On a pool we took at one of my jeep forums I go to seems most cracked between the 100-150k miles....I'm not out of the range yet lol...

 

[Kruse]

Originally Posted by Chris142
Not every 0331 head cracks. Odds are that if it has not cracked yet it's not going to.


Your probably right, but of the three Jeeps that I own, one of mine cracked at about 150K. No overheating, no abuse, no high-revving, it just cracked. I rolled the dice and got a rebuilt TUPY head from Ebay where I purchased the cheapest one I could find.
It did good until the engine threw a rod at about 200K.

 

[puredrive]

Originally Posted by REC
Strange thing is the 2000 came out with the 0331 heads which is known to crack. I don't know the history of this vehicle. Motor has somewhat low oil pressure was 8psi hot idle but 50 psi driving (verified with mechanical gauge) and is little noisy on bottom side but have not had time to verify its from the lower end of motor. Right now running T6 15w40 on this oil change just to see how it does and will go a little longer for next oil change.



the noise could be caused by the flex plate. I got a 2000 Jeep as well, my head did get replaced. I was running 0w-40 german oil and switched to rosella 5w-40. Engine seems to be less noisy. I'm planning on doing a oil analysis soon.