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08 F-150 Hot Rattle at Idle

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I got an 08 F150 with 74,000 miles on it that the guy came in complaining of a driveline shudder. Went for a ride with him and he procedded to tell me that he think's his torque convertor is coming apart. What he proceded to show me was an intermittent rattle and misfire at hot idle. Being customer pay the first thing I did was throw an oil pressure gauge on it and take it for a ride to duplicate it with the IDS. Hot oil pressure in park is at 14 psi according to my gauge. When I put it in gear the oil pressure drops to 10 psi. If I brake torque it up to about 1200 and snap off the throttle it will start rattling and running rough. I know there is TSB 14-0114 for this concern, but I'm worried that it won't fix my issue especially since the vct duty cycle settles in at zero long before the cam oscillation stops and it looks like it's on both banks.

 

VCT OSCILATION.PNG

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14psi is not enough oil pressure to keep the VCT system happy. 15 psi is min book spec.  Good ones i've seen will have 30 @ hot idle.   I call that 5.4 death rattle.  It's engine time.  

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I contacted hotline. They want me to check crank end play and then start looking at cam journals. And they want me to put the vct solenoids in no matter what.

 

The only other one I checked that was good was around 25 psi.

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I know it's overkill, but longblock this thing all day long. If not you are going to end up married to it:

- phasers

- tensioners

- solenoids

- cam journals

- crank bearings

- crank endplay/thrust bearing

- plugged up oil screens

Take your pick .... you may have one as your issue or multiple and it's not cheap if you're wrong.

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