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Discussion Starter #1
I bought the truck with 125,000 miles and so far have put 3.5 quarts in it over 2,000 miles.
My mechanic doesn't think it is normal for this engine to be burning oil this soon, but didn't have time to run a compression check on it this morning. He thinks a PCV valve may be causing it. I am running 5W-30 oil in it. He also thought putting heavier oil in it will help. Is there a PCV valve, and could this be causing problems? Anything else to look for?

It is not usually smoking, exept 2 times after 100 mile interstate trips, it has smoked heavily when I cranked it after sitting for a few hours, like a valve seal problem. But it has never smoked any other time I cranked it. I haven't checked the oil enough to be 100% sure, but I believe the oil consumption is happening mostly at interstate highway speeds(70-80).
I also believe that the fuel economy dropped a mile or 2 after I changed the oil in it. I put 5W-30 in it. Didn't check the oil before I changed it, so I don't know if it was using oil before I changed it. It is getting 18 on the highway now, (78mph, Z71 quad cab 4x4) and about 14 combined. It was doing better than that on the combined. There is no blow by at the oil filler cap at idle, but this may not mean anything.

The dealer that sold me the truck is out of state, and I have no recourse with him. We've already had it out on something else. I did get a 3,000 mile powertrain warranty, but I have little faith in it.
 

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There is no PCV valve, simply a hose running from the valve cover to the resonator box. I recall another member having a similar problem and it turns out the tabs under the valve cover were preventing oil from draining properly, allowing oil to get sucked through the hose, into the intake.
 

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Discussion Starter #3
ssgjurista said:
There is no PCV valve, simply a hose running from the valve cover to the resonator box. I recall another member having a similar problem and it turns out the tabs under the valve cover were preventing oil from draining properly, allowing oil to get sucked through the hose, into the intake.
hmm, that would also explain the smoke when cranking after running at highway speed.

Thanks
 

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I have an 05 Rado with 85K miles thats using / losing oil as well. Usually a quart about every 2k miles. Truck has had only full synthetic used after break in.
 

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Discussion Starter #6
My mechanic removed the return hose, air box, throttle body, intake hoses. Everything from the air filter to the intake has oil in it, so we feel sure this is the problem. haven't got the valve cover off yet. Didn't know you have to remove the intake to get to the valve cover. this is a bit more expensive than I was thinking.
 

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Discussion Starter #7
The mechanic finished mine. From what I understand, the hose is connected to a baffle under the valve cover with some tabs hanging down. That and some gunk stopped up the oil drain. Haven't driven it to confirm that yet.

Sounds like an easy fix, but the intake has to come off to remove the valve cover, so it will be about $400 when finished. Better than a worn out engine though.

My cruise control quit last week, mechanic said it was caused by a tail light bulb gone out.

Now I can go back to work on the purge control valve.

I'm finding it hard to love this truck, is all the little querks gonna come to an end?
 

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Well, with 125K on the odometer, it could be considered that it is going through a mid-life crisis. When you throw a little money at a mid-life crisis, it seems to make things go a little easier. At least this has been my experience........................................ :mrgreen:
 

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Discussion Starter #9
xseler said:
Well, with 125K on the odometer, it could be considered that it is going through a mid-life crisis. When you throw a little money at a mid-life crisis, it seems to make things go a little easier. At least this has been my experience........................................ :mrgreen:
well, that explains my problems with the crotch rockets. :lol:

CORRECTION: The cruise control problem was the brake light switch, not the bulb. I should have known better!! :roll:
 

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Discussion Starter #10
Another clarification: The oil drain hole in the head wasn't stopped up, the factory sealant on the baffle had worked loose, and he thinks the oil was being sucked up through the baffle. The tabs had something to do with it, but not sure what it was. Do not go to the expense of doing this untill I have put some highway miles on it to see if it is still using oil. Did 50 miles today at 55mph, and no oil was consumed, but this isn't a reliable test. I will be able to get on the interstate Friday and do 100 miles at 75mph. I will know for sure then.
 

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SCouch said:
Another clarification: The oil drain hole in the head wasn't stopped up, the factory sealant on the baffle had worked loose, and he thinks the oil was being sucked up through the baffle. The tabs had something to do with it, but not sure what it was. Do not go to the expense of doing this untill I have put some highway miles on it to see if it is still using oil. Did 50 miles today at 55mph, and no oil was consumed, but this isn't a reliable test. I will be able to get on the interstate Friday and do 100 miles at 75mph. I will know for sure then.
keep us posted.
 

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ssgjurista said:
There is no PCV valve, simply a hose running from the valve cover to the resonator box. I recall another member having a similar problem and it turns out the tabs under the valve cover were preventing oil from draining properly, allowing oil to get sucked through the hose, into the intake.
That was me. 20,000 miles since the repair and no problems.

viewtopic.php?f=8&t=49406&hilit=oil
 

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Discussion Starter #13
I ran 70 miles at 75 mph, and another 40 miles at 65 mph with no oil consumption. This distance and speed should have used a quart of oil. So I'm thinking its fixed, but for some reason, I'm still a little apprehensive.

I will continue to post reults.
 

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Good info bro, sounds like you've got a good mechanic.

BTW we don't have serviceable PCVs, they're actually a small orfice hole in the valve cover that the hose attaches onto. There was some issues with them getting plugged up in the earlier 04-06s and the entire valve cover ended up getting replaced but thats about it.
 

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Discussion Starter #15
I wish I had seen exactly what he did, but my understanding is that the baffle is submerged in oil, or has a lot of oil around it on the head. Some of the sealant worked loose, allowing oil to come around the edge of the baffle. The tabs were obstructing something, and he moved them around some, but not sure what he did, but he said it looked sort of obvious. He thought the real issue was the sealant.
 

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I have the exact same problem Scouch describe on the first post, i decided to fix it myself...what a pain to remove the intake manifold.... at the end i did found the valve cover gasket broken and the tabs under the cover too dirty.
 

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is there a sticky on this procedure? the link KCinMI posted isn't good.
 

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even with the valve cover of my mechanic said the baffels are sealed ,no way to clean or bend tabs .... I told hin to spray it out with brake cleaner . has been fine since ...next time I will just blow air in from my compressor and not remove valve cover ,which is a huge job
 

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I just capped mine for a long time ... and stopped the oil burning and smoke . Fixed it when cylinder head went out . no compression on #3 cylinder @ 160,000 miles
 

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Had to pull up a long ago thread. I have somewhat the same symptoms as the OP. If i stay off of the highway my truck never smokes when started. I work about 15 miles form the house. when I go to work i drive on the highway then get off the exit go about .5 miles and park. When I start it up to go home it smokes for a minute. Then I drive home on the highway get off the exit drive about 5 miles and park. when started it doesn't smoke. Really weird. Any ideas? maybe I need to remove valve cover and clean. Is there a better write up? I have a 2004 3.5 Colo. Thanks.
 
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