Old Jeep, Severe duty. Magnum 5.2.

[Merkava_4]

Originally Posted By: Dustmuffins

Not sure on the timing here, but this is what the oil looks like after 4.5k miles.

That's not too terribly bad, but looking at how dark it is there, I wouldn't go past 5k.

 

[meep]

i'd probably do 5k myself just because i care, but 7500 would be easy with the frequent top-offs. My hondas that didn't burn anything looked darker than that with far fewer miles. with his top-ups and a good oil like rotella, I'd say more would be easily ok. can't go by color. color is just the oil oxidizing as its supposed to instead of the metals. and he's doing top-offs.

 

[Dustmuffins]

Originally Posted By: meep
i'd probably do 5k myself just because i care, but 7500 would be easy with the frequent top-offs. My hondas that didn't burn anything looked darker than that with far fewer miles. with his top-ups and a good oil like rotella, I'd say more would be easily ok. can't go by color. color is just the oil oxidizing as its supposed to instead of the metals. and he's doing top-offs.


Keep in mind, I am running Royal Purple (it looses the purple color very quickly) at the moment. should I really be changing that after 5k?

 

[rslifkin]

Probably not. Once you do the plenum gasket, I'd be tempted to pick an oil, run it 7k or so and do a UOA to see how much more life it's got left.

 

[4x4chevydude]

I think the Rotella and amsoil filter is the best plan for this Jeep.

 

[SEMI_287]

I vote for Rotella T6, too.

 

[Dustmuffins]

Originally Posted By: rslifkin
Probably not. Once you do the plenum gasket, I'd be tempted to pick an oil, run it 7k or so and do a UOA to see how much more life it's got left.


That sounds like a good plan. I tried to check for plenum leaks tonight with a propane torch, but I couldn't get the motor to do anything by holding it near the intake manifold. I even held it by the cold air intake to no avail =/. I'm a little skiddish to use more gas because I don't want to make the local news

Rotella t6 really seems to be the popular choice. Looks like my buddy was on to something when he suggested it!

 

[ac_tc]

I have a 5.9 and its been running on cheap xw-40 hdeo for the last years i have once in a while been tempted to change to a
5w-40 passcar syn and also done that just to notice that it didnt use any less fuel and that the oil seems much thinner when its time to change.(the hdeo comes out black but otherwise it´ll look/ feels/ smells unused at an oci of 5kmiles).
Ok, this isnt scientific at all exept for how much money that stays in my wallet, quality hdeo is atleast 1/2 the price of cheap passcar oil...
As for the intake belly pan gasket look up:
TSB 09-05-00
Spark knock and oil consumption due to intake manifold pan gasket oil leak.
http://dodgeram.info/tsb/2000/09-05-00.htm
Read the diagnosing part carefully, you dont whant do this if it isnt needed. (wich sadly mine need...)

 

[rslifkin]

You can't find a plenum leak that way. The test is to (with the engine warm, and not running) disconnect the PCV valve hose, and plug the connection on the PCV valve, as well as the hose. Start the engine, and disconnect the crankcase breather to the airbox tube. Hold a finger over the end. If it lightly builds pressure, then the plenum is good. If it pulls vacuum, the plenum gasket is shot.

The issue is the 2 piece intake manifold, so the gasket failure draws air and oil from the crankcase (lifter valley), rather than externally. A propane torch will never find the leak.

 

[Dustmuffins]

Originally Posted By: ac_tc
As for the intake belly pan gasket look up:
TSB 09-05-00
Spark knock and oil consumption due to intake manifold pan gasket oil leak.
http://dodgeram.info/tsb/2000/09-05-00.htm
Read the diagnosing part carefully, you dont whant do this if it isnt needed. (wich sadly mine need...)


I show these symptoms, as well as the inside of my intake manifold looks black and smells like the dark lord's stool sample(another indicator of a bad plenum gasket).

Originally Posted By: rslifkin
You can't find a plenum leak that way. The test is to (with the engine warm, and not running) disconnect the PCV valve hose, and plug the connection on the PCV valve, as well as the hose. Start the engine, and disconnect the crankcase breather to the airbox tube. Hold a finger over the end. If it lightly builds pressure, then the plenum is good. If it pulls vacuum, the plenum gasket is shot.

The issue is the 2 piece intake manifold, so the gasket failure draws air and oil from the crankcase (lifter valley), rather than externally. A propane torch will never find the leak.


That makes sense.

I did the test you suggested. Was the crankcase supposed to build light pressure in a negative vaccum or blow out light positive pressure? I got light positive pressure out of the crankcase breather hose. I suppose this means that my plenum is good?

It looked like there was oil vapor coming out of the crankcase breather as well. I have oil that comes out of my cold air intake and gets the back of the air filter slightly moist(not enough to actually drip), but my catch can on the crankcase breather hose is bone dry after having it for about 10k miles. (which reminds me... is the catch can supposed to be on the crankcase breather hose or the PCV hose?)

Either way, my intake manifold needs a good cleaning, so doing this should hopefully help me out there, as well as stop the problem if it's an intermittent leak.