Got an interesting noise coming from the rear end of my F250 with 9k miles.. The best way I can describe the noise is that it sounds like a siren in the distance. It seems to only happen between 15-25 miles per hour and will decrease or increase with more power. Any ideas? just take it to the dealer and let the bumper-bumper warranty do its job?

 

Maybe bad clutch packs in the rear diff?

 

No offense to the OP, but whats with these newbs coming on here with brand new trucks asking how to fix and troubleshoot the thing when it breaks. Thats why you get a warranty with the truck, to cover stuff like this. Alright, I'm getting off my soap box.



Is it a 2 piece driveshaft, is it a LS diff? Its hard to diagnose with so little info. It could be anything from a dry ujoint, no grease on the driveshaft slip splines, to improperly shimmed driveshaft carrier bearing, to clutch packs (doubtful), to improperly loaded pinion/carrier bearing, to improperly setup gears. To be honest if you're coming on a forum asking a question like this you're better off leaving it up to the dealer. Aside from that, some of the fixes can be pretty spendy.