I have owned this 2002 SLT+ since it had 4K on it, I have faithfully changed the oil in this 4.7l every 5K. It's a work vehicle and I drive 33K/year on the highway. I have the Enterprise maintenance service and you can only get your oil changed every 5K. I now have 127K on it and it still looks real good, unfortunately it now no longer runs like new. After the last oil change I drove 3.9K and one moring I heard the valves tapping. I checked the oil and it was almost 3 quarts low! I looked for leaks and the filter looked like maybe it leaked, or it could have been just oil from the service, I replaced it. I have no oil in my driveway, the exhaust is black on the inside, I get no smoke when I start it or even drive it. I filled it with oil yesterday and took it on a 150 mile trip..I'm down a quart again! Does this sound like something that anyone has seen before? It's odd that it started all of a sudden and seems to be getting worse! I was going to keep this truck and run it into the ground, it's loaded up and still looks good. I guess I didn't realize that it had one foot in the ground already...may be time to dump it! I would have thought that it could have gone more than 127K!

In 127K I blew up the rear end once ($1400), had the hubs go bad at about 75K ($700), had the steering column freeze up in July, was rearended 3 times (bumper damage only thanks to the class 3 hitch), only had 3 sets of tires, replaced the front rotors 3 times and had them resurfaced at least 3 times, still have the original rear brakes, replaced the windshield once, just replaced the plugs and shocks for the first time in June, replaced the ball joints once and have one going bad, replaced the fan resistor in August after it filled the truck with smoke on a 93 degree day in Myrtle Beach, got as bad as 12.2 mpg and believe it or not as high as 21 MPG (thanks to a Tornado and a K&N), the leather looks no worse than it did when I got it at 4K except for one little spot on the side of the drivers seat (thanks to Lexol), and I have sweat my butt off in this thing every summer for the last 3 years due to the sucky A/C and airflow design that the factory claims meets the spec. Looks like it may soon become a $36,000 boat anchor!

Any suggestions?

 

I would guess that you are losing compression in one or more of the cylinders. Pull your spark plugs if any of them are fouled up with oil that is your problem and you would need a rebuild or a new engine altogether if you choose that route. Good luck with that. I wouldn't wait for an oil change every 5k miles especially if you are using regular oil. I use full synthetic and still change my oil every 3k miles for the simple fact that even if the oil can last for 5k-8k miles the oil filter is only good up to 3k miles. That's just my $0.02

 

I don't know about an 02 but my 99 had a TSB, with a symptom of spark knock during acceleration and/or an above normal engine oil consumption, with no evidence of an oil leak. The cause is a bad intake manifold plenum gasket. Don't know if it's the same for yours or not, but could be something to look into.

 

Don't worry;

here's my list of replacements and jobs done on my 99 Durango 5.9l since I bought it 6 months ago:

Engine completely rebuilt (including one new cylinder head), new radiator, new fan module (export version of Durango came with electric fan), upper suspension arm bushes (both sides), upper ball joint (one side), new battery, rear driver side window regulator, front and rear driver side power door lock. Previous owner had also replaced steering pump.

In truth though, I live in Saudia Arabia - which is probably the most challenging enviroment for a car you can get with incredible heat (over 50 degree Centigrade), sand and road surfaces you wouldn't believe. The previous owner had also severely abused the vehicle in my opinion. Nothing like a zero maintenance regime and off roading it about in the desert to ensure a large garage bill - for the next owner.

The good news is that it now drives like a dream - at the moment - and is a real kilometer eater.

The worst case for your oil leak is that its a cracked cylinder head - which mine had. Symptoms sound the same, using oil but no real smoke coming out the exhaust. The giveaway was that 2 spark plugs were fouled with oil, so off came the clinder heads. Then the real issues were revealed with worn big end bearings ensuring a complete rebuild. Inspection of one of the cylinder heads also revealed a microscopic crack that caused the original fouling...

Good luck...Chris

 

Good write up's guys. I'm thinking look in your radiator for your oil. You might have a bad head gasket or head like the guys explained. Cange that oil every 3k though.

 

Hey, I'm all for changing oil sooner but the Enterprise Maintenance system will not pay for it! The company pays for the maintenance since it's their truck, but I think that it is a poor judgement. I was offered the truck as a buy out for what they owe on it, probably $6500 or so. With a bad engine, it's not worth it, if that is what I have. I even thought of buying it and reselling it if I could make some money. I would not be interested if it has engine trouble.

 

I think your probably looking at getting rid of it. You don't want that motor running 5k in between oil changes anyway. But you can always blow the motor and have them replace it for you before you buy it?

 

Company car eh? Blow that sucker up! They'll have to sell it to you dirt cheap or take an even bigger loss then you can get a rebuild for about +/- $2500. That is one hell of company that's gonna cheap out on the oil changes when you gotta drive it as much as you do now it's gonna cost em more...

 

Just blow it!