drumsforjesus

I have a 2011 F150 with a 5.0L DOHC (Coyote) engine - has 40 k on it. After driving for 20 min or so and removing the oil cap there is quite a bit of exhaust smoke coming out. Sanderson Ford says they did not see much, but I have seen plumes coming out. This engine eats a quart of 5w20 motorcraft full synthetic oil every 1k miles, and after 5k of driving when it is ready for an oil change I can smell quite a bit of fuel contamination in the oil. It seems like the engine has the wear equivalent of over 150 k, based on my 10 years (in the 90's) of experience as an automotive technician. I don't want my warranty to expire and then find out my engine is worn excessively. The dealership wants to charge me $250 to do a compression test, as they say the amount of smoke they see is normal. Any suggestions or personal experience are greatly appreciated.

whomrig

one quart used in 1k miles is not good
can you borrow a compression tester and do the comp test yourself?

drumsforjesus

I suppose I can - any more than 10% variance is unacceptable??

labtek

How is the engine oil pressure? Does it fall back when the engine warms up?

drumsforjesus

Oil pressure on the dash gauge hols at idle and after warm up

7thSeal

Doesn't this engine suggest 5w30 with full synthetic? I think you're running to light of oil?

labtek

Suggest you proceed with compression test either yourself or hire it done somewhere. If the readings are in excess of +/- 10% then together with oil consumption and blowby issues, in my opinion, you probably should start speaking to the dealership about getting a new engine under warranty.

Dustyroads

Manual says 5W-20.

7thSeal

Ah, guess I'm thinking of another V8.

F150Torqued

@drumsforjesus
I'm not running a 5.0 so can't say anything too authoritative, but about all modern engines use crankcase ventilation in the same way. And something doesn't sound right here on only 40K miles. You may have a ventilation line or hose not properly connected - or plugged.


If 'pressure' is building up in the crankcase, that could be the cause your excessive oil consumption.


There should be a hose / line from the air filter box providing filtered air into one valve cover (usually passenger side) and an insulated hose / line from the opposite valve cover (usually drivers side) directly into the intake manifold. Technically - you should have 'negative' pressure in the crankcase / timing cover / and under the valve covers. When you remove the oil filler cap - it should be SUCKING AIR in, not pushing "plumes" of smoke out.


A small amount of compression gasses will always make its way past the rings and into the crankcase - but the intake vacuum pulling air out of the crankcase should darned well stay ahead of it. The crankcase should be air tight with exception of the two above mentioned lines. You can BEST assess the amount of blow by if you seal off the two above mentioned lines on the valve covers, then hold the heal of your hand on the oil filler tube for about 30 seconds. If rings are bad, you'll feel the pressure buildup release when you remove your hand. And you would also see smoke steadily puffing out like the old cars of the 60's. (That's why they implemented the current crankcase ventilation scheme).


Hope you just find something plugged up or unhooked and that cures your oil consumption.