What did you do to your NNBS GMT900 Tahoe/Yukon Today?

[j91z28d1]

The tahoe is also about to take that big boat up a long canyon road, and then back down into a valley.
Hence the urgency!

Silly me decided i better swap out that Coolant recovery tank before the trip, and of course it introduced issues...

I hate it so much haha as I just order a 2nd vaper canister off ebay and just have to cross by fingers and hope it's legitimate not a fake or bad like the first one. cause of seems to be the last oem one listed on the net


ls's are usually eazy to bleed. usually just let it idle till the stat opens with the cap off, then turn it off, let it cool. top off tank and good.


is the front of the engine higher than that back? like you don't have a down hill driveway or something? or wasn't there something about an aftermarket radiator needing a restrictor in one of the small lines?

 

[Just Fishing]

I hate it so much haha as I just order a 2nd vaper canister off ebay and just have to cross by fingers and hope it's legitimate not a fake or bad like the first one. cause of seems to be the last oem one listed on the net


ls's are usually eazy to bleed. usually just let it idle till the stat opens with the cap off, then turn it off, let it cool. top off tank and good.


is the front of the engine higher than that back? like you don't have a down hill driveway or something? or wasn't there something about an aftermarket radiator needing a restrictor in one of the small lines?

Usually I never had an issue also.
the front is higher, and I put it up as high as my Jack would allow and attempted to burp it a few times like that.
It only starts overflowing after I'm working the engine hard, like towing.
Then it will start pouring out after I turn the engine off.


I burped it the best I could with the tool a few hours ago, now it's sitting there still on the Jack with the front in the air.

I also used the tool to introduce more coolant/distilled water since it seemed like it needed it.
Completed by using the overflow/resovore cap that the bottle came with this time around.

I just didn't like the idea of adding more pressure to my cooling system, I kept imagining my heater core popping while pulling the boat up the canyon road.

 

[Grady_Wilson]

And this is the tool i bought.
OEMTOOLS 24444 Coolant System Refiller Kit, 5 Adapters, Eliminate Trapped Air, Test Radiator and Heating Core Lines for Leaks, Vacuum Fill Coolant Tool, Vacuum Leak Tester, Multi https://a.co/d/6MK0ich

Is it right? No clue!

I like the oem stuff usually, and the bright colored case means i have a better chance of finding it later.
Probably years from now if i ever need it again.



Biggest selling item, next day/morning delivery.
It just arrived!

I have been wanting to get one for well over a decade now, just never went through with the purchase.
My 2002 Alitma with the 3.5 can be a pain to get all the air bubbles out of the cooling system, mainly due to radiator being quite a bit lower than the top of the engine.
Maybe I will have to give this one a try, but I hate to buy anything now since I am packing up the house to move.

 

[89Suburban]

I don't understand I never have a problem with mine when I burp it out.

 

[Fless]

I don't understand I never have a problem with mine when I burp it out.

Count your blessings!

 

[j91z28d1]

Usually I never had an issue also.
the front is higher, and I put it up as high as my Jack would allow and attempted to burp it a few times like that.
It only starts overflowing after I'm working the engine hard, like towing.
Then it will start pouring out after I turn the engine off.


I burped it the best I could with the tool a few hours ago, now it's sitting there still on the Jack with the front in the air.

I also used the tool to introduce more coolant/distilled water since it seemed like it needed it.
Completed by using the overflow/resovore cap that the bottle came with this time around.

I just didn't like the idea of adding more pressure to my cooling system, I kept imagining my heater core popping while pulling the boat up the canyon road.

you know what it reminds me of. well it was exactly like that. I've got a truck at work with 2 big tanks in the back, when building it they tapped into the heater core hoses to run to a aux heater core in the back to keep stuff from freezing in the winter. well we forgot it was even there, replaced the radiator and it pucked it's brains out 2 times and only after being used hard in service, at the worst time of course haha. we couldn't make it do it at the shop. we completely forgot we needed to bleed the air out of the rear heater core. guess it all drained out somehow.

its tx and the last thing we need is rear heat, so we looped the hoses and been perfect ever since. I wonder if you've got air in the rear heat and since it's summer the water isnt flowing back there. the air. gets compressed by the high rpm water pump and then went shut down it back. flows so fast the cap can't keep it in.

maybe turn on the front and back heat and let it run for a while? see if you can get some water flowing.

 

[Just Fishing]

you know what it reminds me of. well it was exactly like that. I've got a truck at work with 2 big tanks in the back, when building it they tapped into the heater core hoses to run to a aux heater core in the back to keep stuff from freezing in the winter. well we forgot it was even there, replaced the radiator and it pucked it's brains out 2 times and only after being used hard in service, at the worst time of course haha. we couldn't make it do it at the shop. we completely forgot we needed to bleed the air out of the rear heater core. guess it all drained out somehow.

its tx and the last thing we need is rear heat, so we looped the hoses and been perfect ever since. I wonder if you've got air in the rear heat and since it's summer the water isnt flowing back there. the air. gets compressed by the high rpm water pump and then went shut down it back. flows so fast the cap can't keep it in.

maybe turn on the front and back heat and let it run for a while? see if you can get some water flowing.

I always dread turning on the heat in the summer, with my luck it's the moment the little blend door actuator will fail.




It probably wouldn't hurt to break out my tech2 and do a calibration...

 

[89Suburban]

Spent the morning thinking I'd be able to swap out the front differential, but the two nuts on the driver's side just free-spin, and I can't get a wrench on the top of the bolts to hold them in place while the daka-daka does it's thing. Might have to wait until I pull the engie for the swap to access those two dumb bolts-heads.

Was absolutely covered with Fluid Film, so at least it's nice to know that it holds tight to the frame.

So there are bolts that go through the diff housing themselves into the diff mount brackets aren't there? Then the diff mount bolts are different? I was under the understanding the bolts going through the diff housing into the brackets were threaded holes with no nuts and the diff mou8nt bolts had the nuts? I am pulling mine out soon so I am trying to clarify all this.

 

[j91z28d1]

I always dread turning on the heat in the summer, with my luck it's the moment the little blend door actuator will fail.




It probably wouldn't hurt to break out my tech2 and do a calibration...

I don't know forsure on these trucks, but used be a water valve, normally controlled by vacuum but I guess it doesn't have to be these days. that keep hot water from going to the heater core when max ac was on. Just thinking it's possible that valve is closed and keeping air from getting out. why I was thinking just run max heat front and back. you could also tell if the air isn't getting hot that water isn't flowing right and it's full of air.

but someone else might know if they even have that valve anymore.

 

[gooffeyguy]

you know what it reminds me of. well it was exactly like that. I've got a truck at work with 2 big tanks in the back, when building it they tapped into the heater core hoses to run to a aux heater core in the back to keep stuff from freezing in the winter. well we forgot it was even there, replaced the radiator and it pucked it's brains out 2 times and only after being used hard in service, at the worst time of course haha. we couldn't make it do it at the shop. we completely forgot we needed to bleed the air out of the rear heater core. guess it all drained out somehow.

its tx and the last thing we need is rear heat, so we looped the hoses and been perfect ever since. I wonder if you've got air in the rear heat and since it's summer the water isnt flowing back there. the air. gets compressed by the high rpm water pump and then went shut down it back. flows so fast the cap can't keep it in.

maybe turn on the front and back heat and let it run for a while? see if you can get some water flowing.

I've always, for years, would have the heat on full blast (after the tstat opened of course) when topping/filling the radiator. That'd also mean the rear heat on vehicles that had it. Then just squeeze the upper hose for a bit to burp anything out.

 

[j91z28d1]

I have been wanting to get one for well over a decade now, just never went through with the purchase.
My 2002 Alitma with the 3.5 can be a pain to get all the air bubbles out of the cooling system, mainly due to radiator being quite a bit lower than the top of the engine.
Maybe I will have to give this one a try, but I hate to buy anything now since I am packing up the house to move.

I need one as well. but just not sure which one. my volt as a whole cooling system for the batteries. uses dexcool that's non conductive, but it's 10 years old at this point. I really need to change it, but it's impossible to bleed. you gotta vac fill. I've considered just taking it to a dealer and pay for a flush. but then I remember they have no idea what they are doing these days and anyone trained to work on them would be long gone by now. so I am just going to have to suck it up and buy the tool and do it myself. ugh I hate that we don't have any mechanics left at dealerships that if even trust a oil change

 

[j91z28d1]

I've always, for years, would have the heat on full blast (after the tstat opened of course) when topping/filling the radiator. That'd also mean the rear heat on vehicles that had it. Then just squeeze the upper hose for a bit to burp anything out.

I believe I've read that it's the correct way to do it somewhere, but every car is different it seems. I work on some much random stuff and don't trust my memory enough to say for sure but that sounds correction

 

[89Suburban]

And rev the hell out of it for a bit to purge all those heater cores/lines.

 

[Doubeleive]

maybe that's why I have never had a problem with coolant/radiator changes I take it out and run it up to about 100mph and then I pull back in and TOP IT OFF. if it even needs it.
good way to check if it is going to leak also.

 

[Just Fishing]

maybe that's why I have never had a problem with coolant/radiator changes I take it out and run it up to about 100mph and then I pull back in and TOP IT OFF. if it even needs it.
good way to check if it is going to leak also.

You weirdo!!

 

[Doubeleive]

You weirdo!!

Lol

 

[Charlie207]

So there are bolts that go through the diff housing themselves into the diff mount brackets aren't there? Then the diff mount bolts are different? I was under the understanding the bolts going through the diff housing into the brackets were threaded holes with no nuts and the diff mou8nt bolts had the nuts? I am pulling mine out soon so I am trying to clarify all this.

There are four mounting points that hold the front diff to the truck. On the driver's side there are two frame mounts that have bolts pointed down, with nuts accessible from underneath. The bolt heads are (for now) very hard to access.

In the videos I watched to prepare for this they make it look easy (it actually is), and just zip them off with impact guns. For whatever reason the nuts only loosened a little bit, free-spun to the moon.

The passenger side nuts came off easy-peasy. They actually attach to a intermediate, short, fore-aft mount that is itself bolted to the frame. Ignore that intermediate part, and just unbolt the diff.

There is access to put a socket on top of one of the free-spinning (driver's side) bolts, but I'll have to remove the wheel to have any hope of using two hands to reach both sides of the bolt. The other bolt is buried under the steering rack, and I didn't even bother trying to figure that one out. It's like 95 degrees with all teh humidity here. Like I said before, it'll probably have to be addressed when I pull the engine.

 

[89Suburban]

There are four mounting points that hold the front diff to the truck. On the driver's side there are two frame mounts that have bolts pointed down, with nuts accessible from underneath. The bolt heads are (for now) very hard to access.

In the videos I watched to prepare for this they make it look easy (it actually is), and just zip them off with impact guns. For whatever reason the nuts only loosened a little bit, free-spun to the moon.

The passenger side nuts came off easy-peasy. They actually attach to a intermediate, short, fore-aft mount that is itself bolted to the frame. Ignore that intermediate part, and just unbolt the diff.

There is access to put a socket on top of one of the free-spinning (driver's side) bolts, but I'll have to remove the wheel to have any hope of using two hands to reach both sides of the bolt. The other bolt is buried under the steering rack, and I didn't even bother trying to figure that one out. It's like 95 degrees with all teh humidity here. Like I said before, it'll probably have to be addressed when I pull the engine.

What if you use a pry bar to torque the housing laterally and put clamping pressure on the bolts?


This is one of the videos I was referencing planning for mine. He says to remove the crossmember as well.

 

[Just Fishing]

I have had my front diff in and out several times.
It's pretty easy.

First un bolt the cvs at the diff, use a cheap ratchet strap to compress them.
That will keep them from being in the way, exp when reinstalling the diff.

Remove the front cross member,.
Disconnect the drive shaft and push it out of the way. Bungi cords to keep it clear if you need to.

Then disconnect the wiring.

Then finally, with a jack to support the diff, remove the 4 bolts and lower it down and out!

I like to use a motorcycle jack since i have one i setup for removing transmissions.

 

[89Suburban]

There are four mounting points that hold the front diff to the truck. On the driver's side there are two frame mounts that have bolts pointed down, with nuts accessible from underneath. The bolt heads are (for now) very hard to access.

In the videos I watched to prepare for this they make it look easy (it actually is), and just zip them off with impact guns. For whatever reason the nuts only loosened a little bit, free-spun to the moon.

The passenger side nuts came off easy-peasy. They actually attach to a intermediate, short, fore-aft mount that is itself bolted to the frame. Ignore that intermediate part, and just unbolt the diff.

There is access to put a socket on top of one of the free-spinning (driver's side) bolts, but I'll have to remove the wheel to have any hope of using two hands to reach both sides of the bolt. The other bolt is buried under the steering rack, and I didn't even bother trying to figure that one out. It's like 95 degrees with all teh humidity here. Like I said before, it'll probably have to be addressed when I pull the engine.

So the bolts I circled in green are the ones I thought were "fixed" or "threaded" holes that would not spin out on you or require a wrench on top? The ones in red I am sure they will spin.