The van has 80k miles on it and runs perfectly. Mileage is the same as always and power seems normal.
No standing oil leaks or streaks under the body, or even the slightest hint of blue smoke when cold starting or accelerating, but....
The oil consumption has gone from not needing any addition between changes to add after every tank full.
Best I can recall this all started when I did a cold weather oil change oil change with 5w-20 rather than the usual 10W-30.
Only did this once, and thought the high consumption was linked to the lighter weight oil.
However, even when switching back to 10W-30 the oil consumption is still beyond reasonable.
The exhaust pipe shows carbon, so it seems reasonable to assume that the oil is making it into the intake air or into the combustion chamber.
Anyone experiences something similar and determined the cause?

 

The intake manifold on your engine is two pieces. The manifold itself, and then there is a steel plate on the bottom, to seal it up. The gasket on that plate is absolutely notorious for failing, and leading to high oil consumption. You won't necessarily see blue smoke from it either. My 96 2500 truck would burn north of a quart every couple hundred miles, but, never showed any smoke. (grey smoke at large throttle openings though.....) Pull the doghouse, take off whatever you have on the top of the throttle body, crack the throttle wide open, (engine off....) and look down in there with a bright flashlight. I bet you will see oil pooling in there.

 

To be losing that much oil I'd probably rule out rings or valve seals. On the bottom-side of the intake manifold in magnum engines there is a metal plate with a gasket. When the gasket springs a leak not only is there a vacuum issue but oil is also drawn into the combustion process. Here are pictures of the top of the manifold and the bottom showing the plate.

 

Looking for a local shop to do the work as it's a bit more than I want to tackle on my own.
Thank you all!

John

 

It's really not that bad of a job. Just a bit time consuming. Paying someone else to do it is not cheap.

Also, if your engine has more than 100K miles on it, (or is close) change the timing chain as well. If you are doing the intake anyway, its six more bolts to get to the chain.

 

Plus the water pump has to be removed.

 

Ooops. Valid point. I think I forgot that part, as I was changing the water pump anyway.

 

Yep, but if the pump has a lot of miles, it would be a good time to swap a new one on too. One thing I do is cut some allthread rod to make 4 studs to put in the bolt holes. That way, when you reassemble it, you can drop the intake right down on the heads.Put all the bolts except for those 4 in, pull the studs and put those bolts in and tighten them down. It makes for a nice clean installation.