Well I changed the oil today... got a whopping quart and a half of tar-like oil out of the pan and filter. I added a quart last week when the oil pressure was occasionally dipping down, and then it stayed stable over 35PSI, the other day I noticed it dipping occasionally again. I figured I had the wrong dipstick since it had trouble going in, and I had consistent oil pressure. Well low and behold, I had been running my jeep with almost no oil in the engine.
5 quarts later, the oil pressure is consistently at 35 during idle (just like before), and goes to around 40-45 under load. There are no strange sounds coming from the engine (likewise there were no visible metal filings in the oil), just the ticking of the injectors.
My first question would be, do you think I did any damage to the engine? There was always oil pressure (except during hard turns), I never had a check gauges light, and never heard and still don't hear any sounds that would suggest the engine was or is starved of oil.
My second question would be, where the hell did all the oil go? The exhaust is crystal clear, the coolant appears clean (plus 4 quarts of oil don't disappear into the cooling system), there are no visible leaks, and there is no smoke from oil dripping onto the exhaust.
I am going to be monitoring oil consumption (if any) over the next 100 miles, I only put 800 on it since I got it (and had it inspected, screw that shop), and then am going to change it again (the oil in the pan is a bit dirty now after idling for 10 mins with whatever else had been sitting in there). Also, I had it checked over 2 weeks ago when I had it aligned and they claimed it was fine.
Well I'm going to flush it, but just with motor oil, run it about 100 miles between changes. I am hesitant to use any of that sludge buster because if there is sludge prevent anything from leaking, I don't necessarily want to free it up... Unless you think I should pour some seafoam into my crankcase.
Pull your air hat off the throttle body and look down inside your intake manifold. If there's oil puddling up inside there, your intake needs to come off and you need to put a hughes plenum gasket fix on it.
dont use engine flusher, just change the oil and use a good filter like the purolator pure one.
what does a flush do, if it does any good at all?
it thins the oil out.
Engine oil today is much better than years ago. Used to be engines would be worn out at 70000 miles. I saw plenty of worn valve guides and deep ridges showing a lot of wear from the rings on the cylinder walls.
I've never worked on a 5.9 personally but it is possible that you are leaking oil from the plenum gasket. It is entirely possible that you burned the oil while you drove, or leaked it out into the intake. Four quarts is a massive amount of oil loss so it had to go someplace. Take a look at the oil filter and housing. The O-rings on them tend to go after a while. As for damage. As long as there was "some" oil inside the engine and pressure was OK I don't think you damaged the engine much.
The best way that I've seen to get rid of sludge is to use ATF. Yes ATF. Exchange an entire quart of oil with ATF. Run the car for about 500 to 1000 miles and drain the oil. When you do you should take most if not all the sludge with it.
Hope this helps
1996 Jeep Grand Cherokee. I6 2WD auto 250,000+ miles.
1-2 quarts of diesel fuel in the crank case as a substitute for an equal amount of oil, idle for a few minutes, then drain. repeat if necessary. diesel will not ignite with just engine heat or anything like that.
'97 zj 5.2, some stuff, some other suff, and some things that even work sometimes.
Ok. So I have read mixed things about whether or not I should just get a felpro gasket set, or get a Hughes set with new hardware and a new plenum. Is that over-kill?
I figure I'll do the plugs, wires, cap, rotor, and thermostat(is there any reason to replace it with a 180 degree thermostat, or should I stay stock?), when I do this. Is there anything else that should be done when I have all this apart? Are there any good write-ups out there (I'm still searching).
Will I need any type of specialty tools? I heard something about needing to remove the fuel lines from the rail, what will I need for that?