2008 F350 DRW LB; 110,000 miles; H&S MM tuned since 100k; dpf/doc deleted; my daily driver and weekend/travel hauler; fuel filter changed at 105k; oil filter/oil just changed; usually run mild tune - mild or no power, early TQ lock schedule

For the past month I've been getting a scraping sound, sometimes followed by a rattle that seems to be coming from the air cleaner box/turbo area.

As it's been getting a little worse daily I've only recently been able to isolate it to the turbo because it doesn't make the noise at idle and makes it only faintly when rev'd in park (which is how I heard it there).

I generally don't exceed 2000rpm or 15lbs boost since I drive it for mileage and still owe $ on it but ever since the noise, I've been even more cautious for fear of whatever it is breaking loose.

I think it may also be causing a performance issue with lack of power but I can't really hear the noise when accellerating or at highway speeds so I can't directly correlate the two) but it seems like I can 'feel' the scraping and the two issues did come up close together.

Question - how can I tell whether the turbo is about to let go or what can I do to eliminate the turbo as the culprit? If it is the turbo, am I risking major catastrophe by driving it?

I get no codes on the MM except for P0128 Coolant Thermostat Performance which I get on all cold days <50 and assume it's a thermostat stuck open since it takes a long time to get up to operating temp.

I hope y'all can help, I use to enjoy driving my truck - now I'm just nervous.

 

can you post a audio or video of the sound?

 

I'll try to figure out how to do that - I don't have a 'smart' phone but my digital camera may have recording capabilities. Presuming the truck makes it home!

 

perhaps it is your pulleys on the front of the motor? Belt tensioners?

 

Well, made it home fine but the video/audio will have to wait til after my son's baseball practice.

I thought about the belts/pullies and I've laid under the truck while it was idling watching for any wobbling but I didn't notice anything.

Seems like the higher the engine is 'wound up' before I let off the gas and coast, the louder the sound is and more likely to show up. Happened numerous times on the way home but when I pull up to the stop it seems like it'll idle all day, no problem. I got the boost up to about 17 on the way home just accellerating to speed etc. Monitoring boost and EBP didn't notice any wide or erratic swings.

Thanks for your reply.

 

Well it finally started making the noise at idle one time and I think I've got it narrowed down to the cooling fan and I suppose it could be either the fan itself or the clutch. I took a video of it, this is with the electrical connection off (decided to take it off temporarily to see if it made a difference - apparently it doesn't). I moved around so you could tell that the noise was coming from directly behind the radiator and in front of the engine. I suppose it could still be a pulley. Any opinions? How much would a typical fan/clutch replacement run? I'd love to tackle it myself but realistically it would take me at least a week to get the parts together and carving out time to work on it (all while needing to drive it to work everyday).

 

I got the upper fan shroud off to check out the pulleys and fan and I found this loose assembly on front of the fan. It's the assembly that connects to the electrical connection from the top of the engine mounted fan shroud. What is it and is it supposed to be this loose? It seems like this could very likely be the source of the noise.

 

That is a viscous clutch that also has the capability to electrically lock up as well. Yes that is what it sounds like when they are on the way out. It locks up electrically as your last defence from overheating. Shouldn't be too bad to do yourself in the driveway, the worst is getting it ofrf your pump. Good luck

 

Just got back from the dealership, thought if I could get it taken care of today it'd be worth $500 or so. After hearing that it'd be $950+ IF that turned out to be the problem, I said "I think I'll look into doing this myself". $460 plus $490 labor. Anybody know of a part # and good source for this?

 

Yeah..that is the fan. You can do that job yourself.