grinding noise from rear
 

2009 f150 fx4 5.4ltr ...took truck to autozone for codes and they told me I needed a canister vent valve/solenoid. The reason i took truck in is because i began to hear the grinding sound of the hubs engagine...however..Im wondering if the hub noise would make the sound seem like its in the rear /middle of the truck? So by taking the truck to get the code..Im also wondering if the solenoid is the one causing the noise as well and im misdiagnosing the grinding with the famous hub grinding noise. And lastly,,where is the valve/solenoind location..under truck near tranny?

That's nice. Please post the code, not what the AZ morons told you what you need.

Hubs grinding is usually a vacuum issue. Does the grinding go away when you put it in 4wd?

Thread to read:

https://www.f150online.com/forums/ar...then-some.html

If the grinding is coming from the rear differential, there probably will be a seal leaking. While driving, rock the truck side to side to see if the noise changes. It could be an axle bearing.

AZ code was P0446..EVAP VENT CONTROL VALVE needs replacing as per the AZ scan. Could this be causing issues in vacuum lines that handle the IWES?

You never told us if the grinding goes away if you put it in 4wd..........

Did you read the thread I linked?

I drove it on 2wd and grinding was normal...tried it on 4wd and grinding was still there. Am I to assume that there is definatly a leak along the lines?
Thank you for your input

Not necessarily. Read the linked thread for an understanding of how the IWE system works.

Vacuum disengages the IWE, loss of vacuum engages them.

*IF* it's the IWE that's grinding, either it's not releasing vacuum or it's damaged.

hey jetf16!

My 2009 FX4 5.4 developed a grinding noise at around 120k miles, it was really only apparent at around 30-35 MPH, like when driving into my neighborhood, under light throttle ~1100-1200 RPM. I took it into my local shop, we all agreed it was something in the transmission.

They dropped the pan, looked for debris, found nothing... refilled everything and the grinding went away. I now have 140k miles and no more grinding. I know my transmission leaks from the grommet (passenger side of the transmission) that allows the sensor wires in, especially if it sits for a few days. I think what's going on with mine is that the fluid level gets too low and causes things to slip/grind. Once it was filled back up, it seems fine. Is your grinding in similar conditions?