Complete Rear End Replacement

[Yukon_Canadian]

OK, I've developed a slight howl in the rear end of my 99 Yukon 4x4. I haven't inspected the gears yet (will be this weekend) but I am trying to get ahead of the game in case things aren't good. My first question is would a complete rear assembles from a 1992 Sierra 4x4 be compatible? I believe the only difference is the truck doesn't have the sway bar mounts, not a big deal to me really. It has the right RPO codes G4, G80 (3:73 LSD). From looking under the truck the entire swap looks to be a pretty straightforward job, remove brake lines, struts, sway bar, them leaf spring U-bolts and drop it? If anyone has a link to a YouTube video that would be awesome!!

 

[SunlitComet]

you will want the sway bar mounts. i would keep looking. bedsides you can't say for sure the axle ring size can you of the old one?

 

[Roy Lee Patterson]

I have a 99 Yukon 4x4 4 door and a 95 Tahoe 4x4 2 door, looking at the two I see only the sway bar and brake size on the Yukon as being different. As they are 4x4 the gear ratio has to be the same in this case they both have the G4 option.
Carrier bearings, ring and pinion, crush washer and rebuild or Swap? Also the drive shaft u joint mount is different evidently but a combination sized u joint is available for the adapt.
Let me know what you have found out, I am going under with a tape measure and check the width of the perches and what have you. I have read that the 2wd axles are 2" narrower. Also there is the possibility of upgrade to the 14 bolt rear end but then you could just get a 3/4 ton if you need go to that trouble.

 

[TigerEyz3]

OK, I've developed a slight howl in the rear end of my 99 Yukon 4x4. I haven't inspected the gears yet (will be this weekend) but I am trying to get ahead of the game in case things aren't good. My first question is would a complete rear assembles from a 1992 Sierra 4x4 be compatible? I believe the only difference is the truck doesn't have the sway bar mounts, not a big deal to me really. It has the right RPO codes G4, G80 (3:73 LSD). From looking under the truck the entire swap looks to be a pretty straightforward job, remove brake lines, struts, sway bar, them leaf spring U-bolts and drop it? If anyone has a link to a YouTube video that would be awesome!!

That howl could be the wheel bearings rather than the gears...
As far as the differences between the 1992 and 1999, make sure the:

1. carrier/gear sizing works out - 8.5 vs. 8.625
2. pinion sizes match
3. track widths match

Not a year issue, but make sure the gear ratios match, or you'll have to make "adjustments" later (shift points, speedo)...Though the RPO codes may say 3.73, the gears could have been swapped at some point.

You'll notice the absence of the sway bar... I noticed a difference when I added my rear sway bar...

Good luck with your swap!!!

 

[Erickk120]

Is the howling during decel or accel? or both? Could just be loose pinion preload.

 

[qukon 95]

I got same problem I did replace the the spider gears yrs ago and it fixed the problem my diff cover was leaking so it was low on gear oil truck was sitting alot .did Jack the rear end up and put in gear with stethascope noise coming from diff cover,moved to shaft bearings no noise,no noise at driveshaft hub .Before this I did replace the diff cover and didn't see any pitted gears like the last time.