Absolutely loving my new-to-me 2018 F250 Lariat with the 6.2 Boss…Coming off a 2018 F150 w/ the bullet-proof 2.7 EB… I really lucked out by finding this one in nearly perfect condition with only 40k miles.

Running smooth so far, but after a long commute a few days ago, I heard this noise when I stopped in my driveway and was idling.

The sound doesn’t happen when I turn the truck on, or even after I’ve let it warm up. But it returns after I’ve driven a few miles, and then stop and idle, both in gear and in park.

The sound is hard to describe, as it isn’t a chirp. It’s almost a pulsing medium-pitch drone.

Most audible from underneath around the oil pan, or on either side near the cats. My thoughts are exhaust, cats, fuel pump, oil pump…

Here is the video and thanks in advance for your help!

 

 

Trying to diagnose noises from under the truck are hard but it sounds like a idler or tensioner pulley bearing going bad, the fan is just carrying the sound back. Remove the belt and check them and all the other accessories.

Denny

 

I have a 2019 f-250 with 24,000 miles that makes that exact same noise under the same conditions that you mentioned. I don't remember what the mileage was when it started but if I put a stethoscope on the oil cooler that is where I can hear it the most prominent from underneath the truck , from inside the engine compartment using the stethoscope I can really hear it very prominent around the power steering pump and seems like if I turn the wheel it makes the noise change pitch so I am thinking it is something with the power steering pump or possibly fan clutch, I need to take the belt off ,like Denny suggested , and see if the noise goes away

 

Thank y’all for replying yesterday.

I picked up an automotive stethoscope (have wanted one anyways) and, like said, it is right in the money of the Oil Cooler Pump above the oil filter… wish I could post THAT audio because it’s pretty definitive. I could also hear it in the oil filter itself and the hose coming out of the cooler…

I then placed the stethoscope on the multiple belts (bolts of the belts) and couldn’t hear anything ugly…

Finally, I placed it on the Power Steering pump and heard it too there, but not nearly as clearly as from the Oil Cooler below.

Two questions:

Does a belt drive the Oil Cooler and is it a pump?

Who will be best for the expert opinion?

I am already on the schedule for a couple of recalls to be fixed next week at the Ford dealership down the street…

 

I am pretty certain that the water pump circulates coolant around the oil cooler which I think is why the noise is most prominent in the oil cooler. I think the sound is traveling through the water down to the oil cooler . I can hear the noise if I put the stethoscope on top of water pump, near fan clutch and power steering pump, I just can't pinpoint which one it is because of how the sound travels through everything. The noise drives me crazy not knowing what is so please post back if you find a solution , Thanks

 

My 2018 sounds the same, and has since new. I've been too lazy to take the belt off and try it to eliminate any driven components since I think that's where it's coming from. My worst fear is that it's something in the VCT or timing chain.

So the oil cooler huh? I'll have to look into that, but I'm unsure how, since there is no moving parts in it. Coolant goes in, and coolant comes back out...that's it.

And I already know my fan clutch is shot. Loud squealing/whining on cold starts when the temps are below freezing.

 

My 2017 makes the exact same noise and has been doing so for years. I'm not really concerned about it anymore.

 

I have the same noise . I just used your video to ask the same question, then I saw your post . Any update ?

 

I post another thread of my truck doing the exact same thing. I have a 2018 that I found with less that 30k on it. I have 38k now and it started making this noise. It is driving me insane. I hate stuff like this. I do not want to start throwing parts at the noise. Someone has to know what is causing this.

 

still haven’t figured mine out but I’m fairly certain it’s the transmission . Mines goes away or quiets down a lot when it’s in gear versus park . I ready something about how the thermal valve for the tranny cooler dumps the oil back on to a certain drum and bushing when it’s cold . Might explain why it doesn’t do it till warmed up . I’ve thought about take the valve apart so it will dump oil onto it all the time and see if it helps but I’ve got to many projects to be messing with the only truck runs and moves haha

 

Sounds like a thermal valve that opens once the transmission gets to certain temp. My truck will do this after leaving it idle from a cold star after about 20 minutes. So I do not know if the transmission will get hot enough in park ideling.

 

yah mine will do it if I let it idle for a while or sometimes immediately after putting it in park to get out after a short ride . Then some days it won’t at all . Also have a weird shutter in reverse sometimes so I’m guessing something in the transmission isn’t right

 

did you ever find the cause of the knocking noise you mentioned your truck having in another thread?

 

I haven’t . It’s intermittent, don’t have time to investigate and all the shops around here are backed up a month or more so I’ve just been running it . I suspect it’s transmission related like all the other issues with it