Is my differential toast? 2001 LSD with 210k

[PrecisionX]

Is my differential toast? 2001 LSD with 210k? Fluid is honey colored, dif is hot to the touch and there’s a vibration between 60-80mph only. Nothing before. Shop put a  stethoscope to it and said he can hear the pinion bearing grinding I think? What are my options and is it worth it or is it a wheel balance issue? 

[Slartibartfast]

Rear end failures aren't common in these but it is possible. I'd want to confirm the noise (rear axle jacked up, front wheels chocked, turn the driveshaft by hand and listen) before digging into it, or just drain the oil and see if it's got metal in it. I'd expect the oil to be darker if a bearing is trying to cook itself, unless it was changed recently by someone looking to quiet the noise.

You could try rotating the tires to see if the vibration moves around, but I'm not sure how an out-of-balance wheel would heat up the diff.

 

IIRC the rear third member from an '01 Xterra had a tighter LSD than what's in the R50. Might be a good upgrade if you can find one with the right gear ratio. Later Xterras had very weak LSDs, as did later R50s.

[hawairish]

I'd agree; not common but plausible.  If vibration is the primary issue, I'd check for driveshaft run-out, and play/resistance on the u-joints.  Also, how bad would you rate the vibrations, and do they seem to originate from the front or rear of the vehicle?  Can you feel it in the steering wheel?  

 

If noise is the issue, then I'd look at the diff, but only after isolating parts of the equation (such as removing the driveshaft, keeping one tire on the ground, and lifting the other tire and rotating it to check wheel and diff bearings; or rotating the pinion flange to feel for pinion bearing play).  The color of the fluid might only depend on the brand/color used; i.e., the Valvoline oil I use always has the honey/green tint, but the murkiness changes over time.  It's probably not abnormal for the diff to get hot, but hot is subjective without a number.  My diff gets into the 150°-175° range, measured with a pyrometer in a few spots.

 

If you have any concerns that it's the diff, I'd drain the oil and check for metal as Slartibarfast suggested.

[KiwiTerrano]

My diff whines and has done since I purchased the vehicle. Hasn't gotten any worse in 35000 km. I've changed the oil twice in it.

My flatmates terrano also has a slight diff whine.

[hawairish]

@mjotrainbrain @RedPath88 Can you close this thread, or merge with this other one?

 

  

[RedPath88]

Please direct all comments to the following thread.