Rear differential woes.

[5strmtrp]

My rear GU6 G 80 on my 2014 Tahoe 4wd SSV differential is leaving the chat. Under stop n go, light to medium throttle I get a thunk from the back, now turning into parking spot I get a grind, thunk crack.

I just changed the diff fluid 500 miles ago, showed no signs of wear. Yes I used the limited slip goop from the stealership along with synthetic 75w90 oil.

Rebuilt the yoke and u joint earlier in the year.

???? does any of you know what years are compatible for these trucks??? Silverado, Sierra, Yukon, Burban, Escalade???

Need one fairly quickly like in a week, I’m in Easton Pa area don’t need the suspension bits or brakes just the complete axle.

I have ZERO experience in axles.. Don’t even have the proper tools to set it up.

Thanks

 

[j91z28d1]

I don't have anything helpful to add about your replacement axle. Just curious if you had any issues before changing fluid or if it was just maintenance.

not that I think it would cause the grinding sounds, but the g80 diff is not limited slip, it's a clutched locker and shouldn't have any limited slip additive.

I ended up having to buy oem fluid from the parts department with nothing else added to make mine back to normal after a fluid change I thought would be simple. mine was just annoying thou, yours sounds like ti's much worse.

 

[swathdiver]

My rear GU6 G 80 on my 2014 Tahoe 4wd SSV differential is leaving the chat. Under stop n go, light to medium throttle I get a thunk from the back, now turning into parking spot I get a grind, thunk crack.

I just changed the diff fluid 500 miles ago, showed no signs of wear. Yes I used the limited slip goop from the stealership along with synthetic 75w90 oil.

Rebuilt the yoke and u joint earlier in the year.

???? does any of you know what years are compatible for these trucks??? Silverado, Sierra, Yukon, Burban, Escalade???

Need one fairly quickly like in a week, I’m in Easton Pa area don’t need the suspension bits or brakes just the complete axle.

I have ZERO experience in axles.. Don’t even have the proper tools to set it up.

Thanks

You can have mine, it's been sitting on my driveway forever. You want to stay with the same generation, GMT900 SUVs with JL4 with the wheel speed sensors near each end of the axle tube.

Now is a good time to put a 9.5" axle in it. They sell for pretty cheap on LKQ. Bolts right up, just make sure to inspect thoroughly whatever you buy as they like to drag them through the yard until they get dumped onto a skid.

If you did any pinion work, forgive me if you did this already, you needed to take a rotational torque measurement before the work and add 3-5 foot pounds to the nut after the repair if the crush washer was not replaced. The nut was supposed to be replaced.

 

[5strmtrp]

I don't have anything helpful to add about your replacement axle. Just curious if you had any issues before changing fluid or if it was just maintenance.

not that I think it would cause the grinding sounds, but the g80 diff is not limited slip, it's a clutched locker and shouldn't have any limited slip additive.

I ended up having to buy oem fluid from the parts department with nothing else added to make mine back to normal after a fluid change I thought would be simple. mine was just annoying thou, yours sounds like ti's much worse.

The fluid change was preventative maintenance. I’ve got 160,000 on it, was used for police use & I never changed before. I was getting the truck ready to pull a camper. This noise started just after our trip. So either I messed it up towing or while pulling it started to go due to the stress of the tow.

 

[5strmtrp]

You can have mine, it's been sitting on my driveway forever. You want to stay with the same generation, GMT900 SUVs with JL4 with the wheel speed sensors near each end of the axle tube.

Now is a good time to put a 9.5" axle in it. They sell for pretty cheap on LKQ. Bolts right up, just make sure to inspect thoroughly whatever you buy as they like to drag them through the yard until they get dumped onto a skid.

If you did any pinion work, forgive me if you did this already, you needed to take a rotational torque measurement before the work and add 3-5 foot pounds to the nut after the repair if the crush washer was not replaced. The nut was supposed to be replaced.

Thank you for the info, the rear is a JL4, GU6,G80. Checked my RPO codes this morning.

So as long as I stick with the above “recipe” a 9.5 axle will bolt in???

Again I have never messed with axles so my knowledge is limited.

 

[swathdiver]

Thank you for the info, the rear is a JL4, GU6,G80. Checked my RPO codes this morning.

So as long as I stick with the above “recipe” a 9.5 axle will bolt in???

Again I have never messed with axles so my knowledge is limited.

Yes, all of the 9.5" axles that came out of Denalis or Escalades will have 3.42 gears and the G80 locker and of course JL4. Their RPO code is AXN. Beware, on ebay, they sell everything as an AXN axle even when it's not! Buyer beware.

There are lots of threads on this swap and lots of guys on here who have done it recently that are around to help if you have questions. It would really be no different than swapping out the 8.6" for another 8.6".

 

[j91z28d1]

The fluid change was preventative maintenance. I’ve got 160,000 on it, was used for police use & I never changed before. I was getting the truck ready to pull a camper. This noise started just after our trip. So either I messed it up towing or while pulling it started to go due to the stress of the tow.

sounds like it.. the larger rear end sounds like a good upgrade for you if your going to tow often.

the larger rear end has options for the covers that help with cooling too, like banks makes. where the small one I haven't found one yet.

 

[swathdiver]

sounds like it.. the larger rear end sounds like a good upgrade for you if your going to tow often.

the larger rear end has options for the covers that help with cooling too, like banks makes. where the small one I haven't found one yet.

I don't think Banks makes a 14-bolt 9.5" cover but PML does. IMO, the stock cover works great.

 

[j91z28d1]

I don't think Banks makes a 14-bolt 9.5" cover but PML does. IMO, the stock cover works great.

oh really. I thought that was what I saw when I looked for one for my small axle.

I'd have to look again, but yeah. makes sense the bigger the rear the less you need it anyways. seems there's be a market for one for the small axle. mine was pretty warm when towing. I forget the temp, but I had a temp gun and checked a few times. warmer than I expected

 

[swathdiver]

oh really. I thought that was what I saw when I looked for one for my small axle.

I'd have to look again, but yeah. makes sense the bigger the rear the less you need it anyways. seems there's be a market for one for the small axle. mine was pretty warm when towing. I forget the temp, but I had a temp gun and checked a few times. warmer than I expected

My rear cover has not been hotter than my rotors when driving normally, such as when coming off the interstate and pulling into the nearest gas station.

 

[5strmtrp]

Thanks all for your help, currently trying to find locally the 9.5” axle 14 bolt.

Mentioned AXN to one place in Philly he said both 8.5 an 9.5 axles are AXN. He got my dial tone after he said that!

 

[89Suburban]

Thanks all for your help, currently trying to find locally the 9.5” axle 14 bolt.

Mentioned AXN to one place in Philly he said both 8.5 an 9.5 axles are AXN. He got my dial tone after he said that!

Check these guys out @5strmtrp

Chuck’s Auto Parts - OEM, Remanufactured, and Aftermarket Parts

Chuck’s Auto Parts offers high-quality recycled OEM, remanufactured, and aftermarket new parts. Located in Douglassville and York, PA.

www.chucksparts.com

 

[dkad260]

Have you removed the diff cover yet to see if you have any broken spider gears or side gears? I had a chipped side gear in my Envoy and it mimicked what you were talking about, you might be able to just get by with replacing those four gears.