What would be considered "Normal" oil consumption

[GrantP]

jgillott - Any update on the oil consumption?

 

[jgillott]

Yes, but it isn't necessarily good news. The truck has over 91,000 miles. So well over 10 K and 2 oil changes since my last post in this thread.

After the PCV valve replacement, the oil usage went to almost nothing. I may have added 1/2 quart over a 6000 mile oil change interval. In mid January, I got a call from my wife, who was driving that truck that day, stating that she could smell something funny. She stopped and looked and the entire engine compartment was covered in oil. The dip stick was pushed out and oil had also pushed out around the oil fill cap. I was expecting the worst, but the engine still ran as smooth as could be with no smoke or signs of other issues.

After cleaning everything up I decided to pull that PCV valve that I just replaced. Sure enough, it was covered in a black sludge like coating. Replaced that valve with another new one and it has been fine since.

Obviously, there is something wrong in there that is causing that PCV valve to plug solid. What gets me is that I've never seen an engine build that kind of pressure and still run so well. I guess I'm just stumped at this point.

 

[DonFitzwater]

Have you done a compression test and leak down test yet?

 

[fest3er]

Obviously, there is something wrong in there that is causing that PCV valve to plug solid. What gets me is that I've never seen an engine build that kind of pressure and still run so well. I guess I'm just stumped at this point.

My brother had a '74 Duster with a Tilted Terror. He put plenty of miles on it. Near the end of his ownership, he found the engine kept blowing the dipstick out. Since he wasn't too worried about it, he stuck the dipstick in the hood and put a length of heater hose over the tube to direct the oil below. Engine still ran just fine and produced the usuallly expected torque/HP.

Sludge? That indicates lots of acidic combustion products getting into the oil and overpowering the oil's Total Base Number (its ability to neutralize acids). The dipstick pushed out pretty much confirms it. You can fix the blow-by. Or you can replace the oil filler cap with a tube that provides a bigger crankcase vent; I did this with my '98 12V years ago and it still runs hokey-dokey.

 

[jgillott]

Have you done a compression test and leak down test yet?

I did last summer when I noticed the initial problem. I don't remember the exact numbers, but they didn't show any issues.

 

[jgillott]

My brother had a '74 Duster with a Tilted Terror. He put plenty of miles on it. Near the end of his ownership, he found the engine kept blowing the dipstick out. Since he wasn't too worried about it, he stuck the dipstick in the hood and put a length of heater hose over the tube to direct the oil below. Engine still ran just fine and produced the usuallly expected torque/HP.

I'm thinking that would be a good option if this continues.

 

[MMeier]

FWIW, my 89 4 Runner with the 22 RE has well over 800k on it and does not use... or leak... a drop of oil over a 6-7.5k change interval. Running 10w30 .

 

[jgillott]

New update. Now blowing a grey/black haze out of the exhaust under heavy throttle and smells of burning oil. Such a shame for a truck that has been absolutely perfect front to back before this engine problem.

 

[GrantP]

New update. Now blowing a grey/black haze out of the exhaust under heavy throttle and smells of burning oil. Such a shame for a truck that has been absolutely perfect front to back before this engine problem.

How many miles are on it now? My wifes 03 Jeep with the 4.7 HO is still sucking oil and pushing 150k. It runs perfectly, no smoke, spark plugs are clean, no leaks....I don't know where it's going. I'll probably be passing the Jeep down to my son when he gets his drivers license soon but he's going to have to check the oil at every fill up or it's done.

 

[jgillott]

How many miles are on it now? My wifes 03 Jeep with the 4.7 HO is still sucking oil and pushing 150k. It runs perfectly, no smoke, spark plugs are clean, no leaks....I don't know where it's going. I'll probably be passing the Jeep down to my son when he gets his drivers license soon but he's going to have to check the oil at every fill up or it's done.

100K. Ended up being seized rings in cylinders 6 and 8.

 

[Wayne M.]

The MIL connected to oil usually happens when the wrong grade prevents the cam phaser from jockeying the cam timing on command, as well as the MDS system. It's all electro hydraulic, and the vis of the oil is paramount. The 4.7 may not be so sensitive to this.

 

[jgillott]

The MIL connected to oil usually happens when the wrong grade prevents the cam phaser from jockeying the cam timing on command, as well as the MDS system. It's all electro hydraulic, and the vis of the oil is paramount. The 4.7 may not be so sensitive to this.

Wayne, please pardon the question. I'm really tired right now. What does MIL mean?

 

[Wayne M.]

Sorry J, I'm actually suprised you're on this now...
MIL= Malfunction Indicator Lamp. aka check engine lamp.

Have a a safe trip.

 

[jgillott]

Sorry J, I'm actually suprised you're on this now...
MIL= Malfunction Indicator Lamp. aka check engine lamp.

Have a a safe trip.

Thanks. Yea, I needed to take a little break from everything else going on.

Back to topic, I ended up doing a low budget backyard rebuild on that engine. Pulled it, left the top end alone. Picked up a set of pistons and rings for less than $200 (Probably could have replaced just 2 but felt uneasy doing that). Ran a hone through the cylinders, cleaned and reused everything on the bottom end. New gaskets and put it back together. All together, less than $400 doing everything myself.

It runs great now and oil use is back to where it was as a new truck. I wish now that I would have gone through the heads while I was at it, but I was literally just trying to get it back on the road as cheap as possible.

 

[GrantP]

Ouch. That's not really what I wanted to hear but I appreciate the update.

 

[fest3er]

Wayne, please pardon the question. I'm really tired right now. What does MIL mean?

Prolly doesn't refer to the timeless back-seat driver....

 

[jgillott]

Bringing this old thread back up. Here was my surprise this evening.

Back to it's old games. It's hard to see on this lousy picture but it's down well below the add line on the stick. Approx 1.5 quarts to fill it this evening. Probably just over 600 miles since I checked it last weekend. I'm really getting sick of this stupid thing.

 

[DonFitzwater]

Thinking waaaaaay back......I bought a 1994 1500 with a magnum 318 and it was great. So great that I decided to spend some of my hard earned money on dumb stuff like Mopar valve covers and the like. Well, after that (dealer installed valve covers and pcm) the engine ran harder but developed a mysterious oil drinking habit. Since this was the early days of magnums, the plenum gasket issue was fairly new and nearly unknown to all but the best dealers. I happened across a dealer that claimed they could fix it and warranty would cover it. They pulled the intake and resealed it. No dice......lotsa time went by and many quarts consumed and one day, it stopped drinking oil. That was the day I pulled the Mopar valve covers off and reinstalled the factory covers!!! *Turns out, there was an internal baffle that should have been put in there by the dealer tech but he probably didn't read the instructions. Have you looked at your valve covers? *

You may need to r&r those heads!