DILLARD000

A Bosch 15719 with 24i00 0m610 Long Cable+Plug is good to replace any Ford 4WireNarrowBand Sensor, just ZipTie extra cable away from Hot\Moving parts. The FordMotorCraft parts are 7t4z-9f472-a\7t4z-9f593-a\5f9z-9g444-ab\dy1056, but no need to pay jacked up dealership prices, just buy the Bosch sensors. Again, Bosch is the original equipment maker+supplier for these sensors to Ford factories and dealerships; same item, just a different part number in a different box. Again, upstream and downstream sensors have the same sensor head and the same connector; only difference is the 4wire cable length, so the longer cabled sensor can be used in any position. If you are not convinced or comfortable with this, okay pay for Ford boxed parts and\or dealership labor. It's your vehicle, it's your money, it's your choice. Can't speak\vouch for any other brand of OxSensors beyond Bosch or Ford.

If you got AWD, be sure to change the RDU gear oil and especially the PTU gear oil, at least every 50k miles.

Have the OxSensors ever been renewed; should be changed every 100kMiles\12years as the chemical coating wears out? The KnockSensor (glorified 2wire microphone) issue could be a loose connector or broken\worn\mousechewed cable; that sensor is bolted to the top of the engine block in the "V" under the IntakeManifold; inspect that Cable+HarnessConnector.

MIles on your transmission? Is the ATF level where it should be, check with Transmission warmed up & engine idling is park on level ground? Has the Trans ATF ever been drained & renewed; recommend every 33kMiles\4years? Can try an additive like LucasTransmissionFix or drain+refill with a premium MerconV compatible ATF like AmsOil#HighTempATF.

Could try an oil additive (Lucas "engine honey"), or a premium brand of oil like AmsOil (extra additives for minimizing wear.). Have a personal habit of spraying a little Carb+ThrottleCleaner down the Oil DipTube & Oil Fill, then run engine idling for 5~10 minutes, then change Oil+Filter; believe this helps clear out sludge+dirt deposits throughout the engine. Of course do make sure your oil level is in the upper range on the DipStick.. Also put an eyeball on your 2 belts; a belt or belt tensioner can tick loudly if they're getting worn.

White smoke from exhaust can be an indication of a leaking HeadGasket or cracked Head, allowing water\coolant into one or more cylinders when engin is cold, then closing up as engin warms up. In the V6~3.5L~DOHC Tranverse Engin, with failure of the pumps ShaftBearing &\Or the DoubleFlangeSeal in that damned InternalChainDriven WaterPump (pic below), coolant is dumped into the OIlPan directly below the Pump, making the infamous Oil+Coolant "MilkShake"; serious\catastrophic engine damage can occur, not only overheating the engine & possibly cracking the heads, but likely also damages the various engine bearings (grinding sound?) that should never be exposed to water\coolant. Does sound like a mechanic worked you over.

Not correct for the transverse V6~3.5L\3.7L~DOHC Engin & 6f50 Tran & connected AllWheelDrive PTU. Transmission has its own fully enclosed WALL\CASE; PTU has its own fully enclosed CASE. See pics below. Difference is where the ATF Seal for the intermediate shaft is installed; for AllWheelDrive With PTU, the IntermediateShaftSeal is installed on the right side of the PTU, along with a concentric PTU Seal for GearOil; for FrontWheelDrive WOut PTU, the IntermediateShaftSeal is installed on the right side of the TransmissionCase, since theres no PTU. It is possible to install 2 IntermediateShaftSeals, one on the right side of Trans, another on the right side of PTU; likely a good mod\improvement; ATF commonly leaks at these CVAxle ShaftSeals & drips+smokes+stinks on the exhaust pipe below. The IntermediateShaft extends completely thru the PTU into the right side of Trans; factory installs just one ATF seal on the right side of PTU, so ATF fills shaftway thru the PTU, but does not mix with PTU GearOil. MerconV ATF is in the Trans; 75w140 GearOil is in the PTU; very much different fluids & not intended to mix\interchange.

Need to add 2009 MKX FWD\AWD to your avatar & signaure; makes questions easier to ask & answer. Consider twice draining & refilling with MerconV; see if that clears up the vibes. Alternative is to drain ~1qt replace wih LucasTransmissionFix = extra thick ATF. Is your 2009 MKX FrontWheelDrive or AllWheelDrive? If AWD, have you ever drained\suctioned & renewed the 75w140 GearOil in the PTU. PTU is a NotoriousFailureItem that can be a source of vibes, especially if not serviced at least every 33kMiles\4yrs; preference here is every 8kMiles\1yr with a DIY drain & fill+vent can installed.

Make sure you've got a PDF reader (Adobe or equal) installed.

1st, make sure oil level is where it should be. 2nd, what weight Oil now? When was last Oil+Filter change? Every 4kMiles\6mths. 3rd, when engine has sat for 24hr+, try a PreStart ColdCrank: Key off, hold GasPedal to floor, Key crank 5~10sec, Key off, release GasPedal, start normally This pre-circulates oil thru engine before starting. 4th, consider next heavier weight oil, say from 0w20 to 0w30, or 5w30 to 5w40. Can help quiet older engines. NameBrand FullSyn recommended. 5th, consider an Oil Additive\Treatment; can't recommend a brand, but I've used Lucas as a substitute for 1/2qt; seems little more than heavier oil, but likely helps a bit. 6th, not a kosher SAE recommendation, but I've gotten in the practice of spraying a little CarbCleaner down the OilDipTube & OilFill then idling the engine for 5~10min before changing the Oil+Filter; believe this helps to clear out any oil sludge buildup.

Been there, done that, don't realy want to do it again. WaterPump inner gasket failed (there are two = inner + outer); blew all coolant out thru weephole on front side of block behind alternator. Was very lucky that pumps outer gasket or bearing did not fail; either would have put coolant into oil pan, made a "milkshake" & ruined the engin. Pulled Engin+Trans+PTU assembly from top. New items installed included: * WaterPump with MetalImpeller * Melling HiVol OilPump * TimingGuides+Tensioners+Chains+Sprockets+VVTSolenoids+... * New PTU, modifed with bottom Fumoto DrainValve & Hoses run from TopVentBarb & SideFillBarb to Vent+FillCan underhood between Battery+FuseBox * New Radiator & StainlessFlexHoses * New RadiatorFanControlModule\FCM * New Half+FullSpeed DualTempSwitch wired in parallel as backup if notorious FCM fails again. * ... Before taking any Timing components out, put these jigs/clamps in place on both CamShafts: Timng CamShaft Jigs\Clamps specificly for2007~2010 V6~3.5L~DOHC Engin ATPEAM# AP-04-2619 About $25 on "the river or the bay".

75w140 in PTU 75w90 in DIF Personal pref is AmsOil. Best do this every 33kMiles 4yrs or less.

Not easy or inexpensive. Need to remove timing cover, chains, guides just to get to the pump. Very difficult access with engine in vehicle.

Could be the PTU failing, definitely a NotoriousFailureItem. Miles on the vehicle? How long since PTU GearOil was renewed? Personal preference is at least every 16kMiles\2Yrs with 20oz of 75w140.FullSyn AmsOil or RedLine.