What did you do to your NBS GMT800 Tahoe/Yukon Today?

[Fosscore]

No zerk fittings on new ?

Sorry, yes the Moog came with a new zerk fitting for the outer tie rod. I had not installed it yet in that photo. Also included were a new stop nut for the inner and outer tie rod, nut and cotter pin for the outer tie rod as well.

 

[Scottydoggs]

Fussed with shift settings a bit. Turns out I had torque management turned off. Oops.

Turned on now. Little smoother, but more importantly less stress on the trans.

What I really need is to see if I can load the thing in my computer and tell it to pull a little more timing during WOT shifts. Can't adjust it from the tuner itself and I want it to pull wayyyyy back. Closer to stock. It's exceedingly minor right now

what ya tuning with over there?

 

[SnowDrifter]

what ya tuning with over there?

Diablo Trinity

 

[Thauber]

I did a bad bad thing...

Had the day off, so I did a little maintenance on the Yukon. When I bought it a couple months ago, it had large all terrain tires which were loud, but I could hear some roar that wasn't tires. I looked through the records the owner had, saw the front differential had been replaced with a rebuilt about 18 months and 20k miles ago, took a look underneath and sure thing, all nice and pretty. So I figured wheel hubs needed replacing, especially with the TC activating when barely touching the gas. Well, I got her home and put my set of rims and tires on to be rid of the road noise, and could hear the roar better. Definitely wheel hubs, but also hearing front diff.

Last week I put the new Timken wheel hubs on and noise level was down even more, but there was still some roar, so front diff fluid change time, even though this one hasn't been on her long.

Back to today. Figured a quick change of fluids, and while I was down there I would replace the inner tie rods as well being they had more movement than I care for. Drain plug was a little tight, but popped loose somewhere around 100 ft.lbs. Nasty color for only being rebuilt 20k ago, as well as more metal shavings than I would have expected, but thankfully no pieces. Then I go for the fill plug. It won't budge. Oh shit... I grab the impact and hammer away, but nothing. I grab the torch, get it blazing hot, and try again. Nothing. Son of a ... I just drained the fluid, and can't get the fill plug out. I heat it again and grab a 24" breaker bar and short 6-point socket. It rounds. I grab my sockets meant for rounded bolt heads (the ones you hammer on that cut into the head to grab it), and it just shreds the head. These bastards must have used half a tube of threadlock on this damn bolt. Running out of options and day, I decide to drill through the middle in hopes it relieves it and I can try again. Hole drilled, still won't budge, just shreds more. Go looking for my easy out to hammer into the hole I just drilled, but they have apparently grown legs and disappeared.

So, feeling rather defeated, I did the inner tie rods right quick and hunted down a small piece of tubing. After shoving the tubing through the hole I had drilled in the fill plug, I flushed about a half quart through to make sure to wash out any shavings, replaced the drain plug, and filled it up. As a last ditch effort to reduce chance of leaking out the hole and just as importantly reduce the chance of trash getting in... I used the cap from the quart bottle and hammered it into the hole.



It was a terrible thing to do to her, but dammit, being an AWD version I can't just detach the front end, so I had to improvise.

Any suggestions on removal? I am going to look again for my ease outs or buy some more, but other than that all I can think to do is drill larger and tap it for a new bolt. 20 years I have never seen one THIS damn stuck, and a ridiculous amount of threadlock is all that makes sense to me.

 

[Rocket Man]

I did a bad bad thing...

Had the day off, so I did a little maintenance on the Yukon. When I bought it a couple months ago, it had large all terrain tires which were loud, but I could hear some roar that wasn't tires. I looked through the records the owner had, saw the front differential had been replaced with a rebuilt about 18 months and 20k miles ago, took a look underneath and sure thing, all nice and pretty. So I figured wheel hubs needed replacing, especially with the TC activating when barely touching the gas. Well, I got her home and put my set of rims and tires on to be rid of the road noise, and could hear the roar better. Definitely wheel hubs, but also hearing front diff.

Last week I put the new Timken wheel hubs on and noise level was down even more, but there was still some roar, so front diff fluid change time, even though this one hasn't been on her long.

Back to today. Figured a quick change of fluids, and while I was down there I would replace the inner tie rods as well being they had more movement than I care for. Drain plug was a little tight, but popped loose somewhere around 100 ft.lbs. Nasty color for only being rebuilt 20k ago, as well as more metal shavings than I would have expected, but thankfully no pieces. Then I go for the fill plug. It won't budge. Oh shit... I grab the impact and hammer away, but nothing. I grab the torch, get it blazing hot, and try again. Nothing. Son of a ... I just drained the fluid, and can't get the fill plug out. I heat it again and grab a 24" breaker bar and short 6-point socket. It rounds. I grab my sockets meant for rounded bolt heads (the ones you hammer on that cut into the head to grab it), and it just shreds the head. These bastards must have used half a tube of threadlock on this damn bolt. Running out of options and day, I decide to drill through the middle in hopes it relieves it and I can try again. Hole drilled, still won't budge, just shreds more. Go looking for my easy out to hammer into the hole I just drilled, but they have apparently grown legs and disappeared.

So, feeling rather defeated, I did the inner tie rods right quick and hunted down a small piece of tubing. After shoving the tubing through the hole I had drilled in the fill plug, I flushed about a half quart through to make sure to wash out any shavings, replaced the drain plug, and filled it up. As a last ditch effort to reduce chance of leaking out the hole and just as importantly reduce the chance of trash getting in... I used the cap from the quart bottle and hammered it into the hole.

View attachment 233073

It was a terrible thing to do to her, but dammit, being an AWD version I can't just detach the front end, so I had to improvise.

And suggestions on removal? I am going to look again for my ease outs or buy some more, but other than that all I can think to do is drill larger and tap it for a new bolt. 20 years I have never seen one THIS damn stuck, and a ridiculous amount of threadlock is all that makes sense to me.

Wow that sucks and drives home the message Ive heard a few times- make sure the fill plug comes out before you remove the drain plug. My only suggestion is to heat the case and not the plug itself. If you heated the plug you expanded it and made it tighter, maybe if you heat the surrounding metal it will come out with the easy out.

 

[wjburken]

Wow that sucks and drives home the message Ive heard a few times- make sure the fill plug comes out before you remove the drain plug. My only suggestion is to heat the case and not the plug itself. If you heated the plug you expanded it and made it tighter, maybe if you heat the surrounding metal it will come out with the easy out.

You could also take a drill and put a divot in the plug close to the edge and take a punch and put it in the divot and tap it with a hammer. This puts the torque as far out on the plug as possible and also gives some impact to loosen the plug.

 

[ScottyBoy]

I don't know if they make them for front diffs, but I know that Dorman makes a rear diff cover with a fill hole built in to the cover. I have one on my truck, mainly because my stock diff cover was pretty rusty do I just replaced it.

 

[Thauber]

Wow that sucks and drives home the message Ive heard a few times- make sure the fill plug comes out before you remove the drain plug. My only suggestion is to heat the case and not the plug itself. If you heated the plug you expanded it and made it tighter, maybe if you heat the surrounding metal it will come out with the easy out.

I tried both. I did the casing around it first, and when that didn't work, I tried heating the bolt and then letting it cool, so that it would expand and then shrink to help break the threadlock. Didn't work. Went back to heating the casing. Still nope. The techniques work great for rusted bolts, but apparently not half-tube-of-threadlock ones.

And yes, I don't think I will ever pull a drain plug first again, even if the whole assembly does look brand new.

I don't know if they make them for front diffs, but I know that Dorman makes a rear diff cover with a fill hole built in to the cover. I have one on my truck, mainly because my stock diff cover was pretty rusty do I just replaced it.

These front diffs don't have a cover, but would have been awesome if they did.

 

[Thauber]

You could also take a drill and put a divot in the plug close to the edge and take a punch and put it in the divot and tap it with a hammer. This puts the torque as far out on the plug as possible and also gives some impact to loosen the plug.

Heck yeah, thanks! Will definitely try this when I can. I have done similar using cold chisel on old farm equipment, but didn't think about a nail punch for smaller applications.

 

[wjburken]

I tried both. I did the casing around it first, and when that didn't work, I tried heating the bolt and then letting it cool, so that it would expand and then shrink to help break the threadlock. Didn't work. Went back to heating the casing. Still nope. The techniques work great for rusted bolts, but apparently not half-tube-of-threadlock ones.

And yes, I don't think I will ever pull a drain plug first again, even if the whole assembly does look brand new.

When I bought a used front diff on my 2007 I had the same problem. Went through the same gyrations if big breaker bar, jammed a round-off socket on it, got the torch, etc. the thing that finally worked was taking a punch and hitting it a various locations around the circumference of the plug. Took about 30 minutes and progressively harder blows as I got more and more frustrated.