Humming Noise when slowing down

[GangstaCowboy]

Hello-
This weekend I started to hear a humming noise when driving on the highway. It seems to happen when cruising and slowing down mostly, it definitely sounds rotational. It also cuts out sometimes but always comes back when slowing down. There seems to be a tiny bit of vibration in the car but its hard to say with this rig and the 6 inch lift and tires. No grinding noises or steering issues though. Sounds like it could be a wheel bearing?

 

[SunlitComet]

if it sound hummy then you are likely looking for bearing or gear noises. and i mean gear as in diffy and tcase stuff. do the usual inspections and check for rotational play in your drivetrain and give all the wheel assemblies a good wiggle sideways and up 'n down. if it is a wheel bearing it should stand out easy with your tires setup. in fact the bigger the assemblies the sooner you catch play in the wheel bearings. remove any steering stab prior to testing the whole front end tho.

 

[GangstaCowboy]

Sounds like good advice. What is steering stab?

 

[SunlitComet]

steering stabilizer. such as: http://www.roughcountry.com/steering_stabilizers.html
made by several companies.

---------- Post added at 09:30 AM ---------- Previous post was at 09:28 AM ----------

when installed and trying to diagnose steering issues it can hide them a little bit unless you remove it first.

 

[GangstaCowboy]

Sounds good. I will check out the wheels tonight, hopefully it is a bearing and not the T case or diff.

 

[ScottyBoy]

Do you have drilled and/or slotted rotors?

I get a humming sound when I slow down pretty fast, and I narrowed it down to the rotors. I put a set on my wifes car and then heard the same exact sound, that's when I knew for sure it was the slotted rotors.

 

[SunlitComet]

must me a nbs thing because i have slotted and get no such sound or pulsing effects from them either.

 

[GangstaCowboy]

No I don't, just regular oem style equipment. The noise just started yesterday so I am not sure I will be able to find out where the play is. Hopefully something gives it away. There are so many squeaks and groans with this truck that it's hard to pick up new sounds but I am pretty sure I have never heard this before. Do the rear bearings go out as much as the front? I remember when I replaced the shocks a few months ago the driver side hub was super rusty and the passenger side was in much better shape.

 

[_Dylan_]

rear 10 bolt pinion bearings

 

[GangstaCowboy]

Dylan-
If the noise happens when I let off the gas and slow down could it still be the pinion bearings?