Grinding Noise Mystery

[lytleredranger]

Trying to track down a grinding noise

So I’ve got a grinding noise coining from my front end somewhere. It’s more noticeable at slower speeds. Noise also gets drastically better when brakes are applied.
I can hear it when going straight, and it’s worse when turning left. Goes away when turning right.

A little about the truck:
-2006 sport 4WD w/4.0
-brand new hub assemblies last week
-brand new CV’s last week
-new CV axle seals
-new u-joints in rear driveshaft.

Any help?

 

[Curious Hound]

I think I just responded to you in Facebook.

Get the front of the truck up on Jack stands with the wheels off the ground. Then rotate the wheels by hand. This will get you close enough to pinpoint the noise. The driver seat is too far away. Try to feel for play. Wheel bearings and brakes can make grinding noises. If wheel bearings are bad, the wheel brakes could be dragging. But applying the brakes helps re-align the wheel to where the noise isn't so noticable.

 

[lytleredranger]

Yep, that was me. Figured I would cover all my bases.

Thanks for the advice! My question is, since I replaced the hub assembly/wheel bearing last week with a new MOOG one, is it likely that that is still a culprit?

 

[Curious Hound]

I may have mis-spoken. When you said hub, I thought you were referring to the 4x4 hub assembly. If your truck has unit bearings, and you replaced the unit bearings, then that should not be the problem unless you got a bad one or somehow damaged it during installation. I'm more familiar with old style assemblies where you replace individual bearings housed in the brake rotor.

The 4x4 hub assembly, which is the part that transmits power from the axle shaft/CV axle to the brake rotor/wheel doesn't usually contain the wheel bearings. We may have had some confusion in terminology.

But, my recommendation to get the thing on Jack stands so you can get close to it to wiggle and rotate stuff to pinpoint the problem still stands.

 

[lytleredranger]

Ahh, that was probably on my end. I am new to rangers, used to working on CJ and YJ Jeeps.
This was a unit bearing. The entire assembly.
I am leaning towards something with the brakes, but we will see.

 

[pjtoledo]

what torque did you use on the stub nut?

 

[lytleredranger]

what torque did you use on the stub nut?

If you are referring to the axle nut, I believe 160 ft pounds.

 

[pjtoledo]

yep, spec is 162 lb-ft.
Ford recommends replacing the nut. sometimes I just re-crimp it. it has to be a friction fit on the last few threads.

while it's up on stands try removing the front driveshaft at the differential.
should isolate the front diff and allows you to check the CV at the tcase.

 

[lytleredranger]

Update: Just drove it lunch. The noise appears to mostly go away in 4WD.