1997 Pathfinder 4x4 Rear Differential swap

[AR97Pathfinder]

Hey everyone, the rear diff in my Pathfinder with 235k miles hums pretty loud on the highway between 50 and 70mph and is now making noises at lower speeds. I also hear a growling noise around 20-30mph when slowing down. Recently, when putting the vehicle into drive or reverse, I hear a clunking noise. I had someone shift gears while I was underneath the vehicle and I visbily see the driveshaft rotate at the diff. Nothing is shifting at the tramission mount and no noise is coming from there. 

 

I was thinking of purchasing a 3rd memeber and swapping it out without removing the entire assembly. The plate under my hood says HG46 for the differential and I found one on ebay that appears to be in excellent condition and is also an HG46. However, this one is from an 01-02 frontier 2WD (there is also a plug connector on it, which mine does not have). Will this swap into my vehicle?

 

I read online that the HG46 axles had 31 splines pre 2000 and 33 splines post 2000? 

 

Thank you 

[hawairish]

The 2WD 3rd will physically fit all the same, but if the pinion flange is like how it used to be on trucks with the ABS sensor on the pinion snout, the flange will be about 3/4" longer than models with the ABS sensors at the drums.  Though...I want to say some 2WDs (maybe the QX4?) had a CV-style driveshaft with a different bolt pattern.  Pics would help confirm that.

 

All R50s have 33-spline.  The 31/33 split applies to Frontiers.  Xterras were all 33-spline...you can use a 3rd from a 00+ Xterra or Frontier as well.  Same HG46 ratio.

[AR97Pathfinder]

On 10/7/2025 at 5:35 PM, hawairish said:

The 2WD 3rd will physically fit all the same, but if the pinion flange is like how it used to be on trucks with the ABS sensor on the pinion snout, the flange will be about 3/4" longer than models with the ABS sensors at the drums.  Though...I want to say some 2WDs (maybe the QX4?) had a CV-style driveshaft with a different bolt pattern.  Pics would help confirm that.

 

All R50s have 33-spline.  The 31/33 split applies to Frontiers.  Xterras were all 33-spline...you can use a 3rd from a 00+ Xterra or Frontier as well.  Same HG46 ratio.

Is the abs sensor you're reffering to the electrical sesnor on the diff? If it is, yes the one I am looking at has that, but my diff does not. 

 

It seems like all of the 00+ diff's have that sensor there. 

[hawairish]

9 hours ago, AR97Pathfinder said:

Is the abs sensor you're reffering to the electrical sesnor on the diff? If it is, yes the one I am looking at has that, but my diff does not. 

 

It seems like all of the 00+ diff's have that sensor there. 

 

Not limited to 00+.  The trucks that had it were 2WD...but maybe some really old W/D21 4WD before 4-wheel ABS systems came into play.  For sure, that setup has existed for a long time.  My 98 2wd Frontier had it with the H190 axle, and now that I have an H233B in it, I used an older Hardbody diff to retain the system.

 

Stated differently, it won't matter if the diff has it in your case.  It won't get used, and you won't need to remove it.  But the flange protrudes a little farther than the non-ABS version because it has more components to work it, but the bolt pattern is the same (I overlooked you said it was from a Frontier).  You can't move your flange to housing because it won't clear the snout due to bolt holes that mount the sensor flange.  The longer flange means you need to confirm that your driveshaft doesn't bottom out in the t-case when the rear suspension is fully compressed.

 

Parts look like this:

[Slartibartfast]

11 hours ago, hawairish said:

The trucks that had it were 2WD...but maybe some really old W/D21 4WD before 4-wheel ABS systems came into play.

 

4WD W/D21 did in fact use this setup, from the introduction of our rear-only ABS through to the end. We never got four-wheel ABS.

 

I did not know that the pinion sensors stuck around into the four-wheel ABS on the W/D22. Looks like the 4WD had two rear wheel speed sensors, while the 2WD used the single sensor on the pinion. Weird thing to design twice.