Hey,
I have a 1997 F150 4.2L v6 and I recently had the oil changed (@ 78,500) and Im due in another 1,000 miles or so. A few days ago my oil pressure gauge would drop when braking or accelerating, but then return to normal once I was cruising so I added 3 quarts, but still nothing has shown on my dip stick. Ive consulted the local Ford dealer, he said either Im REAAALLLLY low and 3 quarts (out of the 6 that my truck holds) isnt enough for the oil to register, or, someone replaced my Ford F-150 dipstick with another Ford dipstick and thats why it isnt working. So now for my question: when someone says a vehicle "uses oil" where is this oil going? I plan to change my oil this weekend myself so that I can personally verify that a full 6 quarts has been added (Im beginning not to trust JiffyLube) and I began to wonder where this oil is going because I dont have a leak (at least not onto the driveway) so can anyone tell me if I need to be concerned? The truck: -drives fine -doesnt leave oil stains -doesnt make loud sounds -no exhaust plumes. So I cant figure out where the oil is going. I'd always assumed oil just naturally was burned up over time. Anyways, I am done rambling now. Thanks in advance to anyone who can help.
-M

 

Well . . you seem to have a good basic understanding of what could be happening. Here's what I'd do; Change the oil right away. Make absolutely sure that 6 quarts go into that motor. Then check your oil dipstick right away. It should read mid-way between ADD and FULL. (At least my 4.2 does) This will tell you whether you have the right dipstick. Then I'd check the oil every week to see if the oil level goes down. Don't let it fall below the ADD mark whatever you do. If you oil level goes down, you have the right idea, it is either leaking somewhere or being consumed by the motor as it runs. It doesn't always show up as smoke from the exhaust. We once had a Saturn that consumed a quart per 500 miles and never smoked; figure that out! Best of luck. I hope that your issue was an initial under-fill.

 

acadianabob's got the basics covered. A couple other things you might want to do/consider. when you change your oil, use a razor-blade and mark in the back side of the dipstick with a scratch the exact oil level, monitor it, but don't add unless it goes down into the add, drive 1,000 miles and recheck, add oil to bring it back to the initial level, this will determine how much you are actually burning. 1 qt. per 1,000 is considered acceptable, your truck is getting some miles and depending how hard it is driven or was driven consumption may start to show.

You may see smoke at start-up this typically is valve seals, but to physically see smoke when the engine is running, you are at 1qt every 100-200 miles, that is why acadianabob's Saturn burned oil, but didn't "smoke"

Hope this helps.

(When you do your oil checks be sure to park level both times, and allow the same amount of time for oil to drain back to the pan)

Good Luck!

 

Hey,
Thanks guys, Im looking to change the oil Sunday when I get done with all my Christmas visiting and what not. I am hoping as well that the problem was an initial underfill. I'll let y'all know after I change the oil.
-M

 

Milly, please post your result. I'm curious.

 

bump. . . . so what's the deal?

 

Don’t feel bad if your dip stick doesn’t register the oil correctly. Not many do and many people make the mistake of trusting the hatch marks on the dipstick rather then following the manufactures recommendation.

For example, I have a 2003 Lightning with 3,000 miles on it. Ford specifies 6qts of oil. I believe this is the same amount of all the F150’s.

On my first oil change I bought 6qts of oil and a filter. I pre-filled the oil filter which is a good idea, and then put the remaining 6qts of oil in the motor. Started the truck and let it run for 5 minutes.

Motor was already warm because I ran it for 10 minutes before changing the oil. Once I shut the truck off I let it sit for 10 minutes and then pulled and cleaned the dipstick. I then put it back in and pulled it out to get a reading.

It was approx. ¼” or so from the top hatch mark (some call this the full line). I then took a small screwdriver and marked the dipstick so I know where the full line actually is.

It is just as harmful to have too much oil in the motor as it is to not have enough. If a motor is to full of oil it can damage seals and/or cause excesses foaming of the oil. In the case of Lightning’s, which is debatable, it can cause more oil film in the intake and supercharger intercooler.

In the case of “using oil” this is generally caused by blow-by past the piston rings and I believe Ford considers approx. 1qt per 5,000 miles normal or ok. Some motors use oil while others don’t or very little. It all has to do with tolerances, cylinder bore, rings etc and that is why “using oil” to a point is ok and considered normal.