Back on the forum after many weeks away! Glad to be back and before getting riled up over another oil consumption post please read. I have done a fair amount of research on these issues thus far!
Did some checking some 3k miles after plenum fix because I'm still using oil and discovered the following:
-oil on #8 and # 6 plugs has gone away! So the plenum resolved that issue.
-replaced PCV but used an aftermarket one and when checking it last night it didn't oil dripping from the hose going to intake but all surfaces of nipple on pcv, inside of hose, and nipple on intake did have a sheen to it from a coating of oil.
-I checked out the VC's and no oil leaking there or anywhere else that I could really see on the engine.
-I did the test recommended by Hey You (thanks by the way) where you plug the valve cover pcv port and pulled and plugged the hose going to the air filter and opened oil cap then started engine and she wasn't blowing much air if any that I could tell and that's supposed to be good I think.

Next step is to check to make sure I actually have the baffle under the valve cover at the pcv. I expect I do since it has one on the oil fill side of the engine. If I have that baffle, I'm going to chalk up 1.5 quarts low after 2k miles to the aftermarket pcv. Is this a correct thinking?
I may have also asked this before too but on the driver side of the manifold I have a hose coming off it that is stubbed and plugged. anybody know where that goes?

 

A quart and a half in 2,000 miles, if it's the PCV valve at fault, should show oil spotting on the spark plug(s) nearest the intake manifold port. You might check for that, but it's most important to get a new PCV valve from the dealership -- at about five bucks a pop there's just no reason to screw around with it.

With no excessive blow-by and no leaks, if the new valve doesn't solve the problem I'd be inclined to suspect valve (stem) seal leaks. They're a cheap fix but will eat up an afternoon -- left to progress, they'll lead to an expensive repair when you've got worn valve guides, stretched and burnt intake valves, and a fouled catalytic converter.

 

Good compression/very little blow-by doesn't give any indication of what your oil control rings are like. Unfortunately......

I still have excessive oil consumption after doing my plenum as well. I have some seepage around the v/c's, but, not enough to account for the volume of oil I am going thru, and no evidence of leaks on the ground either. I do get a nice cloud when I first drive it for the day.... but, unless my valve guides are REALLY bad, I don't think even that could account for the amount of oil I go thru. (a quart about every 100 miles or so.....)

The engine still runs good, for the most part (sensor issue still.) Doesn't blow clouds while driving except for about the first half-mile of the day. No evidence of the oil going anywhere else either.... so, I am forced to assume my oil control rings aren't doing their job..... wonderful.

 

Thanks guys. The dealership pcv is definitely worth a try. I would have put that in when did the plenum but didn't catch that note on this forum to buy from dealership. I don't ever get any noticeable smoking even at start up for my truck. It never smokes noticeably enough for me to see while driving at least and no leaking anywhere. It's dry all the way around. I can't imagine that as much oil as I've used that it could all be pulled through the pcv even if it's aftermarket and I don't have a baffle(will find out tonight for sure on baffle) but anything is possible I guess. Next step is to compression check the engine.
Would it be a good enough indication to just pull all the plugs and connect up to each cylinder one at a time and cranking engine for about 5 seconds then reading pressure?

 

You can do a compression test on a cold engine.... it just isn't as accurate. (less chance to burn hands though....)

Run the test, then, put a teaspoon or two of oil into each cylinder, and test again. See if the numbers change much.

 

Thanks Hey You. I'll do that. I checked the vc and it DOES have a baffle in it so I'm less inclined to think that much oil is being sucked through but at high throttle and wrong spring rate of aftermarket pcv i suppose anything is possible. I expect to see some compression issues but I don't ever see any smoke so it may be some mild leaking that just keeping a check of oil will be sufficient. I'm lucky if I put 4k miles a year on this truck but I love her!
Will inspect the plugs near the pcv port just to see if they are wet. that might tell me that pcv is worse than expected but i'm not counting on it. thanks for the tips!

 

An aftermarket PCV usually has a higher flow rate than the OEM unit, replace it with a dealer part and see what happens.

 

where are the oil control rings located im having the same problem, and a couple more but just taken it one thing at a time for now

 

On the pistons. And your problem is not the same if you have not replaced the plenum gasket.

 

1+ on plenum...just picked up the pcv from dealer today! Looking forward to driving it for few months to see what kind of improvements I might see! Holding out that this is going to solve the oil drinking problem! i'm not convinced but a lot of you guys seem to think it's possible! Would be nice to rule out this last thing before diving in on bigger problems! Thanks all!