I read through other posts on here but have come up empty. So today I was backing up my 11000# fifth wheel at the campground when at 1500-2000 rpm I hear this awful squeaking sound coming from under the hood. I heard it the whole time while backing up and under a load. I never heard it once going forward. So when I get home I put it in reverse and hold the brakes(this time) and again I hear this squeaking sound coming from under the hood. I get it up to 1500 rpms or so not moving just holding it and the more throttle i apply the louder the squeaking gets. Anyone have any ideas on this. Now remember the truck is not moving its just spooled up, holding the brakes. I think that maybe something is wrong with the turbo, but I dont want to jump to conclusions.

This truck is a 2001 F350 SRW CC LB 7.3 161,000 2 owner miles, 4 inch turbo back FLO PRO Straight pipe, and gauges everything else stock. Im scratching my head because I'm not moving so what is moving that is making this horrible sound. Thanks for any and all Help you can provide.

 

It *could* be the exhaust to outlet clamp, or the bolts that hold the outlet housing to the exhaust turbine housing. The engine will torque over to one side in drive, and the other in reverse. If the clamp or bolts are loose, it could conceivably create a leak when the engine torques over and puts pressure on it. If a motor mount is weak, it could also allow the fan to contact the shroud. If it isn't one of those things, I'm not sure what else to check without being there to hear it myself.

 

How hard would it be to change out the motor mount if that is whats bad?

 

I'm honestly not sure; I haven't had to change a motor mount in one of these trucks. When I start unbolting motor mounts, the whole engine is on its way out of the truck. I'm inclined to believe your problem probably isn't actually a bad motor mount, though. Have you had a chance to look for any evidence of the fan rubbing, or an exhaust leak?

 

okay today i had someone sit in it and rev it up in reverse. Brakes held just like before and we started at 1200-1300 rpm and thats the rpm where we initially heard it. Its tough to hear over the straight pipe so I got underneath and recorded a 40 second Audio/video of this sound. It seems like it is coming out of an area on the truck behind the oil pan I believe I tried feeling with my hands areas all over the truck underneath while this was going on to see if I felt any vibration Im starting to think now that maybe its something in the transmission. Could it be a torque converter maybe? Is that possible does anyone know. Someone smarter than me please help. THanks