What could cause the oil in a 4.0 to increase in volume (and not coolant)?

[Larry Hampton]

My buddy has a 4x4 Explorer with a 4.0/auto and he's changed the oil, test drove, checks level, it's fine, drives for a few days, rechecks level and it's up a few inches on the dipstick. He's wondering if the tranny can pump fluid into the engine somehow.

 

[Fred]

Could it be gas? Maybe a leaky injector? Smell the oil. Just a thought.

 

[Richard L]

Improperly checking the oil. It should be checked with the engine warm and shut off for several minutes. If it's checked while the engine is running or too soon after shutting down, the dipstick may show a higher oil level due to the oil splashing around while driving etc.



Also, since it occurred after an oil change, perhaps he just put in too much oil??



...Rich

 

[Don Donaldson]

To answer the first question, I do not believe there is anyway for trans. fluid to get into the motor. There is a seal similar to the rear main motor seal in the transmission front bellhousing for the torque converter. if it where to leak it would simply make a mess in the transmission bell housing as the drippage got spun around by the flywheel, starter, ect. You see the front of the transmission where it links up to the motor (via torque converter) is simply open air and there is no way for it to get into the motor. If the oil is milky then a water passage is now part of an oil passage.

My thought would be as Richard L stated that the truck was not on level ground or something.

My only other question would be if his engine is having any trouble with blow back (blown or damaged piston ring). but that would be accompanied with the engine smoking a lot:wacko:.



sounds like nothing to worry about

-Don D.

 

[Wes Davis]

If it has a mechanical fuel pump the pump has failed and letting gas into the oil through the diaphragm.

 

[Larry Hampton]

He's checking the oil correctly and not too much oil. hadn't thought about fuel though and it's not milky.

 

[Richard L]

Larry,

Gasoline cannot get into the oil on a fuel injected 4.0 becaue they do not use mechanical pumps, they are electric fuel pumps, and they are located in the fuel tank.



If excessive fuel was leaking past the injectors you would get a CEL indicating a rich mixture, black smoke would be coming out the tail pipe and perhaps even flooding the engine.



It cannot be transmission fluid since the transmission is electtonicly controled and there is not vaccume lines or anyway for transmission fluid to get into the engine.



It is probably not coolant since the engine would have by now been overheating and the oil would be milky and you would likely have steam coming out the exhaust.



If none of the above are true, and when there is no other logical explaination, then I can only assume someone screwed up and put too much oil in, or they are not checking the oil correctly. Since the extra oil appeared after an oil change, my guess is that too much oil was put in....There are no other explainations.



Wouldn't that solve our oil crisis if we can put 5 quarts into an engine and get 6 quarts back out?



...Rich