Loosing oil

[TMutziger]

My brother drives a bone stock '05 six speed with 190,000 miles on it. Lately he says its been using a couple gallons of oil per change (5000-7000 miles). No leaks anywhere on the truck. No extra/odd colored smoke. Blow-by doesn't appear to be excessive. Checked the tubes to the intercooler, no oil residue there. Can't figure where that much oil could be going. Is it possible on these engines for engine oil to end up back in the fuel system? I commonly here of it happening the other way around with fuel in the oil. He pulled his fuel filter and said it was black, but I've heard that is also common on a common rail. Any thoughts or ideas where it could be going? Thanks

 

[sag2]

If it isn't going out the turbo most likely a dusted engine from dirt getting past the filter. Pull the oil fill cap at idle and compare the "puffing" to your truck. If it is worse than yours, dusted engine.

 

[TMutziger]

That makes sense to me and I will look into that. He's run the factory air box and filter since the truck was brand new so it makes me wonder how it could've ingested that much dust. The reason I asked about the oil getting back into the fuel is because it happened with one of our trucks at work recently. It was an International DT466 that was using gallons of oil every couple days. No leaks, smoke and not in the intercooler. Finaly dipped the fuel tank and there it was, black as coal. O-rings were bad on the injectors and leaking engine oil back into the fuel return line. I know its a completey different engine, just wondering if it is a possibility.

 

[Deleted member 995608]

My truck (225K) continues to use oil in between changes also. At first, I thought it was the new CJ oil's so I switch to Amsoil 15w40 CI+. No change, still losing oil, . . . . . . somewhere.

 

[jgillott]

I had the same problem a little while back, not quite as much oil, but significant amounts. Sent a sample in for an analysis and everything came back looking OK. After I changed the oil this last time, it seems to be back to the normal consumption that I have seen since new. I have not been able to pinpoint what the problem is/was. If I wouldn't know better, it seemed like the consumption that some have reported when trying to run oil intended for a gasoline engine in a diesel. I always do my work myself, so I know what went in it. The problem has me stumped till today.

 

[TMutziger]

Interesting, thanks for the replies. He did say that the last week or so, it hasn't used as much. And he doesn't do his own oil changes. Not sure what oil they're putting back in, I thought Rotella. I'll have to ask him. I tried getting him to send in an oil sample but he hasn't yet. Still no thoughts about the oil getting back into the fuel system? Not possible?

 

[cerberusiam]

The fuel return gallery in the head is pressurized with return fuel where under the VC is not pressurized. Fuel in the oil if an o-ring goes bad, not oil in the fuel. Evidently the DT466 has an open fuel return system with pressurized oil on one side.



I just want to clarify something, a couple GALLONS of oil per change???? A couple quarts is no big deal and normal with high miles or the engine not being worked all the time.



A couple gallons is far form normal and if it isn't coating the underside of the truck, the only place to loose that much oil is out the turbine side of the turbo. A small steady loss will never show in the exhaust or be noticeable.

 

[TMutziger]

Thank you for that info. That's kinda what I figured, just wanted to rule it out for sure. And yes he said at the worst, it was using almost two gallons in a 5000-7000 mile period. I never checked the intercooler myself cause we live 80 miles apart. He said he pulled the boot off and it was clean in there. I just asked him last night and he said the oil level hasn't changed at all in the last week and a half (1000 miles). I guess we'll keep an eye on it and wait till it gets worse or performance and fuel economy start to drop. Are there any other tests/checks I should suggest to him? Thanks again

 

[cerberusiam]

Maybe a compression test to see if there are broken rings. Possibly a crank case pressure test to see if the blow by is too high.