my truck has been sucking down oil for about three months l have no oil leaks no knocks in my engine and no black smoke the white smoke l do have can be compared to starting you're vehicle on a cold winters day after a while it goes away

Probably rings going, it is burning the oil while your driving and your just not seeing it, if it was the valve seals it would run into the cylinders when you park it overnight and you would see blue smoke in the morning, pull your plugs to see if they are fouled, and it should show which cylinder(s) are bad, you should do them all while the motor is apart anyway.

these engines had major issues with the intake ''belly pan'' gasket. u cannot see the gasket unless u look in through the throttle body with the blade all the way open. l have replaced many of these gaskets due to oil consumption problems. when the gasket leaks, the lifter valley is exposed to manifold vacuum & oil is sucked in through the bottom of the intake. take it to the dealer & have them do a minimum airflow test. that will tell if its leaking or not. sometimes, if the gasket is really blown out, u can see a loose piece of it through the throttle body on the bottom of the intake.

you need to replace the belly pan gasket under the intake manifold on those engines,the quality of the fitment of the gaskets from new were poor to begin with,so be sure to seal it good when you change it,good luck with it.

l just sold my 99 model ram and those engines had major problems with intake gaskets leaking and causing them to pull oil in the combustion chamber and burning it,they would also do this when the valve stem seals went bad on the,if its got over 100 thousand on it you might want to check the intake gasket and pull a valve cover gasket and check and see if the valve stem seals are still their and in place,that may be where most of the oil is going to,good luck and happy new years,

Yes, its the lower intake plate gasket. You cannot see in through the throttle body good enough. Pop the TB bolts out and take the TB off to the side. Look down in the intake with a flashlight, you will see a bunch of oil puddled at the rear of the plate to manifold interface.
Straight forward job. Good time to do the t-stat and bypass hose too.
Good luck~Dan