2010 Harley F-450 Driveline Noise

robsmth41 · January 25, 2012

Ok, this has been an ongoing repair over the last 6 to 8 months. First time he came in complaint was whining in rear of the truck. Tech narrowed it down to the stump. Rebuilt the hog and shipped it. Customer drove for a couple of months with no real change. Backlash and gear pattern was almost perfect. Came back about a month ago and after everyone on my team, including myself as well as the original tech drove it for a few days we couldn't duplicate. customer came in and drove it for us. He was able to duplicate. The noise only comes in between 58 and 61 miles per hour after the fluid is warm.

It traced back to the rear diff. No visible defects, good wear pattern on new gears, axles appeared to be true, good fluid, nothing really to point at!

We order and replace the entire center section. Drove with customer again. Noise still there but not as severe this time. Brought back the shop, spun the driveshaft 1/4 turn, noise still there, but even less than previous. Still there nonetheless.

My thoughts are leaning toward rear axle housing at this point.

Any thoughts?

Keep in mind this is an F-450 with the 5 ton rear diff, tried new ring and pinion, then new center section, then rotating the driveshaft.

ETS · January 25, 2012

Is front end rack able to do 4 wheel alignments on larger trucks? Set up and compensate all 4 heads, This will show axle tubes that are bent by rear toe readings. Although problem is probably in machining center itself. Still may be interesting test. Also good to do with collision work. had county Police Cruiser off 1/4 inch on left rear. Looked like old dog going down road.

I have seen shipment damage on rear housings before on cars and lighter trucks. Traced to rail shipper from being strapped down too tight on rough tracks. All of which had noise issues early after in service dates.

Ford dealer rebiult my 01 F350 dually 3 times and never completely cured whine. They refused 4th try at 38k. Noise on light pull 47 to 61. Probably needed housing also.