So I'm I'n search for. A 2004 and up f150. I found one I'n great shape for 5,000 dollars with 120,000. Drives good but it has a knock I'n the 5.4 engine. It gets quieter when the engine is warm. Should I avoid this truck or will I be okay with purchasing? Only thing holding me back from buying truck is the knock

 

Bought a 2004 with 72000 miles. Also had a knock issue shortly after purchasing it. Turned out to be cam phasers. Common issue, my price was 1200 to replace them. Engine much quieter.

 

I have an 08 with the 5.4l 3v engine, truck rattled, barely idled, switched to 15w-40 diesel oil (better detergent package) noise gone immediately after oil change, been chasing the noise for months.

 

has that oil affected the performance at all?do the camphasers still retard at about the same time on start up?

 

Oil had been working well, dealer switched oil back to the 5w-20 semi-syn motorcraft oil, within 100 miles, truck started knocking and rattleing again, switched to 0w-40 synthetic diesel oil, with in 5min truck back to purring like a kitten.

 

noisy lifters ide say.i fixed mine yesterday,three lash adjusters and one severly knocked around roller rocker.the roller has close to about 2 to 3 mm movement.im amazed it didnt fall out.cam severly scored,i just rubbed the roughness down with a bit of sand paper.the motor has never sounded or ran so smoothly,ive never replaced the phasers and i dont beleive i need to as i cant hear anything.after i found the issues i done a little bit of reading and apparently the number 2 and 3 pistons on your passenger side have oil flow issues which results in a failed lash adjuster or tappet,the only preventative step to sort the issue out is to run the recommended oil 5w 20.if the thick oil is doing the job though,why not use it!

 

if its coming from under the rocker cover it could be a lash adjuster,cheap fix.

 

Do not run diesel oil in a mod motor. The oil pump isnt set up to push that thick of an oil. You can cause oil pressure issues to the cam caps(cam bearing surfaces) if the oil is too thick. If the oil pressure does get to high then the oil pump bypass will open.

 

it seems like alot of guys are going to a little heaver oil to increase oil pressure to eliminate the cam phasers from rattling,can we install a new oil pump !!!

 

Use a FRPP high volume oil pump and pick up tube and you should be ok.