96 dodge ram 5.9 doing strange things

[96Indyram]

I have a 96 Indyram 5.9 thats doing strange things and it has me perplexed.



A little history on the truck. i bought it new in 96, then traded it off in 99. truck had 27k miles on it wen traded off. Found the truck again on a car lot in 2004 and bought it back...truck had 96k miles on it. the low oil light came on driving it home from the car lot.

I checked the oil when I got home and it was full but old, so i did a oil change. When the oil came out it looked like black coffee..total viscosity breakdown. I pulled the pan and the inside of the motor was cooked on varnish black/gold in color....so I knew i was on borrowed time.

I replaced the oil pump with a Melling, put it back togther and everything seemed ok.



fast forward to now.... truck has 140k and everything on the truck is still original except for the oil pump 40k miles ago, water pump replaced last year, and plenium gasket ( stupid 2 piece inkake )and thermostat replaced last month...due to burning oil like described below.... and still got the same issue.



Now ....this is what has me scratching my head.

i can start the truck after it sits all night...no smoke at all out the tail pipes. I can rev it up...no smoke. I can let it idle for a hour...no smoke. I back down the driveway...no smoke.

I put it in drive and head down the road...and its rolling coal out the exhaust for about 1/4 mile like a diesel then it clears up.

Also my oil light is coming on now when I come to a stop light...etc.. when the rpm drops to idle. It did not do this before I replace the plenium gasket. oil is full, oil was changed 800 miles ago.



So I am at a loss here. Compression test is still great on all cylinders.

No knocks, pings, or strange noises. it still runs like new.

If valve guide seals were bad it would smoke at first start. it only does it when I drive forward. i guess I could drive in reverse everywhere but prefer not to..LOL



Could this be a simple fix of something I am missing?

Or do you think i got all the goodie out of the Ol'Gal and its time to park it and start restoring it?

I was planning on a 408 and a frame off restoration when she died anyway.



Thanks in advance for any suggestions/answers to my dilemma.

 

[RonD]

Could be as simple as the valve seal on one intake valve is gone or badly deteriorated on one of the rear cylinders.
Forward velocity causes oil in the valve cover to flow to the back and increases it's level, where it is sucked in.

Having a look under the valve covers might provide more info.
You can change valve guide seals with the heads on.
Valve covers off, rockers off, valve spring compressor, air compressor and hose with spark plug hole adapter(or a rope that fits down spark plug hole), and a handful of new valve guide seals