so i was backing into my yard just now to unload my bbq and i hear this loud "knocking grinding" sound coming from by the engine so i asked my fiance to drive...only when in gear not when in neutral (i have an automatic) its not in 4x4 and hasn't been in months...i just had the oil/filter and fuel filter changed Friday...dont remember hearing this at all but its also been cold so ive had my windows up...its a very noticeable unhealthy sounding knock...it seems to be coming from the middle of the engine...what do you think...im under the 36kmi i have 34kmi almost but the dealer is an hour drive...i dont know if i should drive it as is or take it to my local mechanic to see whats going on??? what do u guys think it could be?

 

where did you get your fluids changed? any chance they screwed somthing up?

 

no its the guy i always take my vehicles to...great mechanic...and i checked all the fluid levels and everything seems fine???...just checked the truck again and it is making noise in neutral and park as well as in gear...and its rpm sensitive in that it gets faster as the rpms get higher....i searched on here and im thinking maybe tensioner pulley...idler pulley...or cam phazers??

 

I wouldn't drive it, any noise is wear. You could be killing the life of your engine.


Does the oil filter look clean, as if it was new? What brand is it?

Does the oil look clean, not black/metallic? Is the oil full?

Does the engine make a knocking noise while revving the truck in park? If its engine related it will make a noise in park too.

If it doesn't make a noise in park check your transmission fluid. It should be a clean red. It should not smell burnt.

Look at the rear axle does it look oily near the breather tube (center left of axles, rubber hose attached to the top) or oilly near the wheels?

 

oil filter and oil is all new....both motorcraft i purchased them....oil is full and clean...knocks in park as well as in gear...also gets faster as i stated before when revved...takes a minute for the knocking to begin...drove it to the dealer today (about an hour drive) the mechanic came out to the truck with me and said he believes it to be coming from the cats?? and is going to order new parts....im not sure exactly what he's ordering since he said he was checking on some sort of ford database or something...my repair bill is still open and he said i can drive it so if something were to happen i would assume itll be covered...im almost at 34kmi which is y i want to be sure to have it taken care of...im going to look at the axle next time i go out to the truck but the noise is def coming from the bottom/rear of the engine bay?? hope he's right and fixes it...