I have a 1998 ford f-150 4x4 with the 4.6 triton that has 100800 miles and has just recently started consuming oil. I have only been about 2300 miles on an oil change and when i checked it yesterday it was 2 quarts low it was not registering on the dip stick. The motor does not leak at all on the ground, it is not spraying any under the hood, and there is no burning or smoke coming from the tail pipes i cant even smell any scent of burning oil. I have kept the truck in perfect running order and have always changed the oil every 3 so it is strange to me that is would all of sudden start doing this. Go figure it hits 100 thousand and it starts having problems. Anyone know what could be causing this? Also the check engine light has been going on and off a buddy of mine told me that could be caused by an off and on engine knock. But if anyone knows i am all ears.

 

Could be a clogged EGR valve, that'll cause them to use oil. Unless you did something evernight to cause your rings to fail, Id check that first.

 

id say worn rings but 100k isnt that many miles. i had a 87 dakota with 246K burned a quart a week but that many miles without a rebuild thats to be expected.

 

Dumb question, but did you do the last oil change, or are you assuming the shop put in the correct amount?

 

A new PVC valve wouldn't hurt either. Top the oil off and check it weekly also take it for a ride and have someone follow you as you get on the gas to see if it smokes.

You can pull the plugs and take a compression reading.... that will tell how heathly your motor really is.

 

I would second what Dave68iou1 and RacingJake mentioned. Also make sure you are parked on level ground. I hate to sound **** but it happens more than you realize. If you discover it is consuming oil check that the "O" ring is not missing or broken under the oil fill cap. Also change the PCV as others mentioned. Good luck.

 

I'd put money down that we have another 4six with bad head gaskets and leaky oil lines...

If so, welcome to the club

 

No i do all of the oil changes myself and put in the correct amount each time. it just started doing this about 6 thousand miles ago, two oil changes ago. I checked the "check engine light" and it was throwing a EGR default code, but can that cause it to really consume more oil?

 

Simply, yes, it can.

Leaky oil lines were a fairly common problem on that motor, but don't start tearing into your motor until you're sure it's really burning the oil. If it doesn't leak, the only other place for it to go is out the tailpipe, so get a friend to follow you around to see if the motor smokes.

You can try from a cold start, immediately get out and watch the tailpipe. If the motor is burning oil, it will burn the most when it's cold (seals/rings expand when hot).