Hi Juan this is lostrider, Ford states that it is normal for the engine to consume 1 quart for every 1500 miles, allot of it is based on the type of oil and filters used and the type of driving that the truck is being used for, with it being a 2006 model, there is what is called an oil consumption test that needs to be done on the truck to determine the amount of oil that is being consumed, its best to have the dealer perform this test, that way it is documented and will get better attention from Ford if there is a consumption concern, here is a copy of the procedure from the Ford service manual, hope this helps.
Excessive Engine Oil Consumption
Nearly all engines consume oil, which is essential for normal lubrication of the cylinder bore walls and pistons and rings. Determining the level of oil consumption may require testing by recording how much oil is being added over a given set of miles.
Customer driving habits greatly influence oil consumption. Mileage accumulated during towing or heavy loading generates extra heat. Frequent short trips, stop-and-go type traffic or extensive idling, prevent the engine from reaching normal operating temperature. This prevents component clearances from reaching specified operating ranges.
The following diagnostic procedure may be utilized to determine internal oil consumption. Make sure that the concern is related to internal oil consumption, and not external leakage, which also consumes oil. Verify there are no leaks before carrying out the test. Once verified, the rate of internal oil consumption can be tested.
A new engine may require extra oil in the early stages of operation. Internal piston-to-bore clearances and sealing characteristics improve as the engine breaks in. Engines are designed for close tolerances and do not require break-in oils or additives. Use the oil specified in the Owner Guide. Ambient temperatures may determine the oil viscosity specification. Verify that the correct oil is being used for the vehicle in the geographic region in which it is driven.
Oil Consumption Test
Once all of the previous conditions are met, carry out an oil consumption test.
Post Checks, Evaluation and Corrective Action
NOTE: An oil-soaked appearance on the porcelain tips of the spark plugs also indicates excessive oil use. A typical engine with normal oil consumption will exhibit a light tan to brown appearance. See Spark Plug Analysis in this section for details. A single or adjoining, multiple cylinder leak can be traced by viewing the tips.
Recently serviced by 2 licensed mechanics to evaluate oil consumption. Their diagnoses, contamites in the air chamber, serious contamination in the air filter from internal chamber, contamination in the crank valve. Attempted to remove spark plugs, some were too tight. What is your opinion on this diagnosis?
Thank you for your early response.
Your welcome, from what their diagnosis indicates is excessive blow by, piston rings?, base engine problem.
~How many miles are on the truck?
Thank you again, there are no special service messages for oil consumption, or base engine oil concerns, if there is excessive blow by in the engine then a cylinder leak test needs to be done to determine if the piston rings or base engine is at fault, the problem there is that the spark plugs will need to be removed to perform this test and on the 3 valve engines there is a problem with the plugs breaking off in the cylinder heads, there is a special tool to remove the broken plugs from the heads that the dealer has, the truck is out of warrenty by mileage but still in by time, so the dealer may be able to get you some assistance from Ford on the engine repairs, but first there going to have to do the oil consumption test to see if it is out of Fords specs and perform the diagnosis, they wont accept any outside diagnosis towards any type of repairs, here is what the cylinder leak test consist of.
Cylinder Leakage Detection
When a cylinder produces a low reading, use of a cylinder leakage tester will be helpful in pinpointing the exact cause.
The leakage tester is inserted in the spark plug hole, the piston is brought up to dead center on the compression stroke and compressed air is admitted.
Once the combustion chamber is pressurized, the leakage tester gauge will read the percentage of leakage. Leakage exceeding 20 percent is excessive.
While the air pressure is retained in the cylinder, listen for the hiss of escaping air. A leak at the intake valve will be heard in the throttle body. A leak at the exhaust valve can be heard at the tail pipe. Leakage past the piston rings will be audible at the positive crankcase ventilation (PCV) connection. If air is passing through a blown head gasket to an adjacent cylinder, the noise will be evident at the spark plug hole of the cylinder into which the air is leaking. Cracks in the cylinder block or gasket leakage into the cooling system may be detected by a stream of bubbles in the radiator.
Thanks for all your help lostrider!