Front Diff?

[ncburch22]

When I'm driving any speeds 10mph+ I hear a very faint hum coming from the front end area. Not necessarily a grinding or whining noise. It slows down its speed of the hum if I take my foot off the accelerator and gets fast if I increase the speed. I can't hear it with the windows down or with the radio/AC up high. It's also hard to notice over my Duratracs. I purchased used with around 80k miles. Does this sound like bearings going out in the differential?

 

[colorover]

Could also be a hub bearing. Both fronts on mine started to go around the same mileage.

 

[ncburch22]

@colorover i was going to put that on the list of probabilities as well. I checked front diff for any signs of leakage to cause bearings to foul, but couldn't see anything notable.

Luckily, if it is front wheel hub assemblies, that's a lot cheaper than differential issues. My extended warranty covers mostly anything outside of drivetrain. Imagine that

 

[colorover]

^ A tech at my dealership misdiagnosed mine at first as a front diff bearing. As I talked them into doing a rebuild v a replacement, I confirmed it wasn't the culprit. At around 100k, lots to start worrying ($$$) about... So far I have done both hubs, LCAs and tie rods. At some point upper control arms and rear arms and hubs will also need doing.

 

[ryanjl]

Amazon Prime has the complete Timken hub assemblies for under $160 each. I agree that it all adds up, but, in the scheme of things, that isn't much for an LR4 part.

 

[ncburch22]

Yeah I'm ordering those Timken hubs. I couldn't find any exterior evidence around transfer case, drive shaft, or diff as far as seals being broken go

 

[roverman]

Wouldn't hurt to also change your diff fluid and look for excessive filings.

 

[jlach993]

Yeah I'm ordering those Timken hubs. I couldn't find any exterior evidence around transfer case, drive shaft, or diff as far as seals being broken go

Hey man i just came across your post, did you ever figure what your noise was? I’m having the exact same symptoms to a tee. Any help would be greatly appreciated!!!

 

[ktm525]

Put it on a lift, get all four wheels free and put it in gear running. Stethoscope all your concerns.