Pulsing/Dopplering whine after Superlift install...

[kythri]

Please see original thread here:

http://www.explorerforum.com/forums/showthread.php?t=222755

I had originally thought that this was due to an extreme angle on the CV shafts, but I went out today and dropped the load on the torsion bars to almost nothing, and the whine is still there.

It's a pulsing deal - high-low-high-low wah-wah kind of sound (I just love trying to describe a sound via text).

It seems to be coming from both sides, but I don't appear to have anything rubbing anywhere. The CV shafts have been lowered to the point that they're virtually flat, no bend in the joint at all.

Any ideas?

 

[fsumotorhead]

are the axle nuts throught the wheell bearings torqued correctly?

What kind of shape are the tires in?

 

[Yomie]

Wheel bearings sould like they are going out

 

[kythri]

Brand new axle nuts (came with the new CV shafts), torqued to whatever the Haynes or Chilton book we were looking at specified.

Brand new tires, pretty sure it's not tire whine.

Wheel bearings? Where are these at? I've got new CV shafts, and the hub assemblies were fine, prior to the lift.

 

[fsumotorhead]

bearing are in the hub assembly

if over tightened, aka impact tightened, preload could be high and "imprint" the bearing race, causing a growl

If left too loose, they would make noise as well, and in both cases would eventually fail

aggressive off road tire make a ton of noise, new or otherwise

older tires are often the culprit for sounds like you are describing, often due to the lack of rotation


i would suggest swaping back to the original tires and test drive it, if the noise is still there, it's not your tires


also since you just lifted it, retighten EVERYTHING, could be you accidently left something loose, i know i've done it, or maybe something worked it's way loose already

 

[Cobraguy]

if over tightened, aka impact tightened, preload could be high and "imprint" the bearing race, causing a growl

I strongly disagree. No way an impact overtightens that nut and causes this noise. Not the way those bearings are designed.

If left too loose, they would make noise as well

In fact, if left loose, the bearing will completely fail soon.

aggressive off road tire make a ton of noise, new or otherwise

I'm betting this could be the problem.

i would suggest swaping back to the original tires and test drive it, if the noise is still there, it's not your tires

This is the place I would start. Just try any tires at all and see if it changes the noise. It does sound like tire noise to me that you are trying to describe.

 

[kythri]

I'll swap back to my 31x10.5x15 sloppy old mud tires and try, no problem, but these are BFG All-Terrains, which I would think would be significantly more quiet than what I had before.

I'm used to the tire hum from the old tires (they've whined since they were new, open tread seems to do that), and this just doesn't seem the same, plus I'd think I'd hear it from the back as well.

Thanks for the advice - I'll get out there as fast as I can (work this week) and get the old tires back on and see how things go...