Tow Vehicle Rearend Noise 3500 Chev Dually

Rusty Davenport · 06-28-2007, 02:04 PM

Chevrolet 3500 series dually, 2000 year model 7.4 engine---GM rearend 4.10 ratio---owners manual says it requires synthetic rear end grease when replacing. I'm hearing a high pitch "sing" between 60 and 65 mph...just enough to get your attention if the CD player is not loud enough, 40,000 actual miles, is there an additive that might help this and is there any need for alarm outside of just an annoyance ????

06-28-2007, 02:04 PM	#1
Rusty Davenport Senior Member Join Date: Jun 2005 Location: Nashville N.C. Posts: 506 Likes: 4 Liked 101 Times in 27 Posts	Tow Vehicle Rearend Noise 3500 Chev Dually Chevrolet 3500 series dually, 2000 year model 7.4 engine---GM rearend 4.10 ratio---owners manual says it requires synthetic rear end grease when replacing. I'm hearing a high pitch "sing" between 60 and 65 mph...just enough to get your attention if the CD player is not loud enough, 40,000 actual miles, is there an additive that might help this and is there any need for alarm outside of just an annoyance ????