2wd5spd

i have a 2000 4.2l f150. it has 133k miles on it. i have recently been adding around a quart of oil a week to keep it to where it should be. I am using 5w-30 oil (its what the owner's Manual recommends!). it is not leaking any oil(no oil spots under my truck when parked). From what i can tell, it is not burning any oil either. i don't smell any burnt oil, nor is my truck smoking(except for when the engine is cold). Does anyone have any idea on what could be happening?

Good old Bill

Pull your plugs and inspect. Perform a wet/dry compression check. If the oil isn't leaking externally, it has to be using it internally.

Mod (Ret.)

If it puffs smoke at startup, it"s valve guides/valve guide seals. As good old bob states, do or have a dry and wet compression test. It involves removing all the plugs, then inserting a compression tester in one cylinder at a time, cranking the engine, and writing down the measured cylinder compression readings, then doing the test again, only a squirt of oil is done in each cylinder before the test to see if the squirt of oil increases the reading (oil helps saeal old, worn rings). The best and worse cylinder on the dry and wet readings are considered to determine if it's worn rings, or bad valve guides/valve guide seals.

2wd5spd

ok, ill work on getting that test done soon. thanks guys

smokeshow81

id be checking your rad fluid to see it it's mixing in there as well

bobkyle2

Catylitic convertors.....If its not leaking.. or smoking.. or mixing somewhere else.. .. Id' say catylitic convertors...

Also pull off a line to the brake booster an make sure its not getting in there

2wd5spd

I'm loosing it less and less. Seems like its fixing itself

bobkyle2

Are you sure you are filling it correctly?

2wd5spd

Yes. I'm filling it right. It lost some after I had valvoline change it, so I'm pretty darn sure I'm doing it right lol

sea_goin_dude

When you change the oil with that many miles I'd add one qt straight 40 w and see if that helps. Might boost that 5w30 up a mite. Won't hurt anything either. Have seen this help of some high mile rigs before.