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

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new2yukon

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Fun weekend part 1.
Rad flush and fill
Thermostat replacement.
Passenger side spark plugs.
Valley pan gasket.
4 post coolant hose gasket.
Knock sensors replaced and wire connection spliced and replaced.
Fuel injector o rings replaced, brown and blue.

Tomorrow is the driver side spark plugs, the intake manifold gaskets, the differential cover and drain and fill. Painting the calipers red. And looking for an AC leak.
There's a lot I don't know. Like what's a valley pan gasket?

But what I do know is many have had the fittings go bad at the heater core. One of yours looked yellowish and it may be something to consider. Just my $.02.

But really...what's the valley gasket?
 

new2yukon

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Today, I had a brake pedal that went straight to the floor. Sure enough, a puddle of brake fluid back by the gas tank. Haven't investigated yet, but I do have a complete set of lines waiting to be swapped in; I guess that time is now!
We've had 3 lines go on vehicles in our house due to rust over the years. I dont understand as much of a safety item the lines are that they arent stainless from the factory. Seems like it should be a requirement???
 

Doubeleive

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There's a lot I don't know. Like what's a valley pan gasket?

But what I do know is many have had the fittings go bad at the heater core. One of yours looked yellowish and it may be something to consider. Just my $.02.

But really...what's the valley gasket?
exactly like it sounds it is in the top center of the motor under the intake manifold, it's also where the knock sensors sit.
 

DenaliReyes

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There's a lot I don't know. Like what's a valley pan gasket?

But what I do know is many have had the fittings go bad at the heater core. One of yours looked yellowish and it may be something to consider. Just my $.02.

But really...what's the valley gasket?

Funny you mentioned the yellowing, because it started leaking this weekend after I placed as new thermostat.
Its where the knock sensors sit in. I took it off and changed the gasket. It was the farthest I've been inside an engine. Got to see the cam. Pretty cool.

I finished reinstalling everything g else with new I take gasket. New plugs and wires. Next weekend it's the o ring pick up tube. That's going to be a beachT
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new2yukon

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Funny you mentioned the yellowing, because it started leaking this weekend after I placed as new thermostat.
Its where the knock sensors sit in. I took it off and changed the gasket. It was the farthest I've been inside an engine. Got to see the cam. Pretty cool.

I finished reinstalling everything g else with new I take gasket. New plugs and wires. Next weekend it's the o ring pick up tube. That's going to be a beachTView attachment 249058 View attachment 249059 View attachment 249060 View attachment 249061 View attachment 249062
So....the knock sensors are under the 2 round black covers that have the white wires, correct?

And why would I see oil on the front portion of that flat rectangular cover plate? I did valve covers a couple yrs ago and still get seepage in the middle flat portion under the butterfly.

Edit: ok. Saw YouTube video. How many estimated shop hours for the valley and intake gasket?
 
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Doubeleive

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So....the knock sensors are under the 2 round black covers that have the white wires, correct?

And why would I see oil on the front portion of that flat rectangular cover plate? I did valve covers a couple yrs ago and still get seepage in the middle flat portion under the butterfly.

Edit: ok. Saw YouTube video. How many estimated shop hours for the valley and intake gasket?
I would use some engine degreaser and pressure wash the entire area (from a moderate distance) and then see if it leaks fresh
 

Scottydoggs

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i broke down and ordered 4 new window regulators. they all screech some, and the back pass side is now doing the herky jerky.

also set a code for the fuel tank pressure sensor. bought one of them as well.

so ive got a few things to fix. 4 reg's, tank drop and p/s the rear blend door actuator, had that part for months now, and still need to replace the wiper fluid pumps grommet. and with that im sure more plastic line will break and need to be patched up again.
 

DenaliReyes

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So....the knock sensors are under the 2 round black covers that have the white wires, correct?

And why would I see oil on the front portion of that flat rectangular cover plate? I did valve covers a couple yrs ago and still get seepage in the middle flat portion under the butterfly.

Edit: ok. Saw YouTube video. How many estimated shop hours for the valley and intake gasket?
Yes, I went the cheap way and bought 2 connectors to splice with the existing wiring. I just cut off the old.ones, they were brittle and broke as soon as I touched them. The knock sensors were originals I think, old and rusty. Bought all new parts from Rockauto.

It could mean your intake is taking in oil from the vacuum line of the pcv stem off the driver side valve cover. Mine was doing exactly that. Then it started to white smoke at start ups. I changed the intake manifold gaskets and it also added an oil catch can and that solved the smoke and the oil.

I changed the valley pan gasket because I'm already in there. Might as well change everything I can whilst the intake is off.

I broke the oil pressure switch like a dumbass I over tighten it. Snap. Cheap aluminum. Luckily the father in law came to the rescue and delivered one I just bought off oreillys.

Its slot of work I think but if you like doing your own mechanics. It will be cake. Easy. Take your time and do it right. I had my book with me just incase.

Sorry for the long story, but I would say it would take about 5 -6 hours. If you take everything off. Unplug all wires, remove gas line, vacuum lines, fuel injectors, coil packs, intake manifold, knock sensors, and then cleaning it all up. U might as well since u got it all off. Then put everything back together to spec. Yeah, it's a fun time. Enjoy! I did.

This is my second attempt .
 

Rocket Man

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i broke down and ordered 4 new window regulators. they all screech some, and the back pass side is now doing the herky jerky.

also set a code for the fuel tank pressure sensor. bought one of them as well.

so ive got a few things to fix. 4 reg's, tank drop and p/s the rear blend door actuator, had that part for months now, and still need to replace the wiper fluid pumps grommet. and with that im sure more plastic line will break and need to be patched up again.
Are you sure you don’t want to just replace the fuel pump assembly while you have the tank dropped? That sensor comes as part of that assembly. Guess it depends on how many miles are on it.
 

Scottydoggs

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Are you sure you don’t want to just replace the fuel pump assembly while you have the tank dropped? That sensor comes as part of that assembly. Guess it depends on how many miles are on it.

its got like 122,000. might have been changed already. its not the worst job really. and im out of gas. so ill have to 5 buck it for gas here and there till the parts comes in. work is a whole 5 mile round trip. so i can keep the tank on E easy enough.
 

Scottydoggs

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got that rear blend door actuator installed today. so nice to have cold air back there again.

might do the washer tank grommet tomorrow after work. if its not to damn hot out.

window regs should be here in a few days as well as the tank sensor. rockauto won the window reg purchase. 117 shipped for all 4 of em.
 

915_Tahoe

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Can you all show me pics of Hoes(Indigo Met. in color) with these type of 20" stock wheels. can't seem to find any tahoes with this wheel option. i could have sworn i saw them on @05Single or someone else.


Would have been nice if i added a photo of the rim. lol

WHEEL.jpg
 
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Scottydoggs

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spent like 30 minutes looking for the washer pump grommet. finally found it, now i know ive read ppl have swapped the pumps from the bottom and not had to take the battery and tray out and the whole tank. so i tried the easy way, no dice for my huge hands. by that point i lost all ambition lol

tracking tells me one of the regulators showed up. need to take a walk down to the lobby and find it. thank god for ra using blue ra tape lol you have to see all the boxes down there, its crazy how many are piled up daily.
 

lowpost99

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Should have died today...I-75 S in ATL/Marietta at Mount Paran. Swerved suddenly left into the HOV lane to avoid a driver coming into my lane, over-corrected and went across all 5 lanes, hit an Army transport vehicle, bounced off of him, back left across 2 lanes scraped the right of another car, and then hit the concrete wall. The driver that came into my lane keep going and my truck looks like a total loss. It's been fun reading this forum, but I think that I'm toast. I'm trying not to feel bad about the love and time that I've put into maintenance, upgrades, repairs, transmissions, body work, and other pride inspired self starter type efforts that I've put into this truck, and just instead remember that it likely saved my life. I will not buy anything less than a full-size. Maybe I'll get lucky and find another one nearly like it.
 

Rocket Man

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Should have died today...I-75 S in ATL/Marietta at Mount Paran. Swerved suddenly left into the HOV lane to avoid a driver coming into my lane, over-corrected and went across all 5 lanes, hit an Army transport vehicle, bounced off of him, back left across 2 lanes scraped the right of another car, and then hit the concrete wall. The driver that came into my lane keep going and my truck looks like a total loss. It's been fun reading this forum, but I think that I'm toast. I'm trying not to feel bad about the love and time that I've put into maintenance, upgrades, repairs, transmissions, body work, and other pride inspired self starter type efforts that I've put into this truck, and just instead remember that it likely saved my life. I will not buy anything less than a full-size. Maybe I'll get lucky and find another one nearly like it.
Oh wow, I’m so sorry about your truck but so glad you’re ok. I sure hope you can find another one to replace it with and make it your own again. I’m glad it saved your life.
 

Tonyrodz

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Should have died today...I-75 S in ATL/Marietta at Mount Paran. Swerved suddenly left into the HOV lane to avoid a driver coming into my lane, over-corrected and went across all 5 lanes, hit an Army transport vehicle, bounced off of him, back left across 2 lanes scraped the right of another car, and then hit the concrete wall. The driver that came into my lane keep going and my truck looks like a total loss. It's been fun reading this forum, but I think that I'm toast. I'm trying not to feel bad about the love and time that I've put into maintenance, upgrades, repairs, transmissions, body work, and other pride inspired self starter type efforts that I've put into this truck, and just instead remember that it likely saved my life. I will not buy anything less than a full-size. Maybe I'll get lucky and find another one nearly like it.
Sorry to hear that. Vehicles can be replaced--people can't. Look at it like this--she did her job---You walked away! Glad you're ok.
 

3Dog

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Should have died today...I-75 S in ATL/Marietta at Mount Paran. Swerved suddenly left into the HOV lane to avoid a driver coming into my lane, over-corrected and went across all 5 lanes, hit an Army transport vehicle, bounced off of him, back left across 2 lanes scraped the right of another car, and then hit the concrete wall. The driver that came into my lane keep going and my truck looks like a total loss. It's been fun reading this forum, but I think that I'm toast. I'm trying not to feel bad about the love and time that I've put into maintenance, upgrades, repairs, transmissions, body work, and other pride inspired self starter type efforts that I've put into this truck, and just instead remember that it likely saved my life. I will not buy anything less than a full-size. Maybe I'll get lucky and find another one nearly like it.

Dang, that sucks. Glad you are OK, it wasn't your day.
 

Sam Harris

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Should have died today...I-75 S in ATL/Marietta at Mount Paran. Swerved suddenly left into the HOV lane to avoid a driver coming into my lane, over-corrected and went across all 5 lanes, hit an Army transport vehicle, bounced off of him, back left across 2 lanes scraped the right of another car, and then hit the concrete wall. The driver that came into my lane keep going and my truck looks like a total loss. It's been fun reading this forum, but I think that I'm toast. I'm trying not to feel bad about the love and time that I've put into maintenance, upgrades, repairs, transmissions, body work, and other pride inspired self starter type efforts that I've put into this truck, and just instead remember that it likely saved my life. I will not buy anything less than a full-size. Maybe I'll get lucky and find another one nearly like it.
Holy shit man! Glad you’re ok! I hope you can find a comparable replacement. Good luck to you, and I imagine at least a little healing is needed. Even if it’s just bumps and bruises. Take care, and don’t go anywhere.
 

05Single

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Should have died today...I-75 S in ATL/Marietta at Mount Paran. Swerved suddenly left into the HOV lane to avoid a driver coming into my lane, over-corrected and went across all 5 lanes, hit an Army transport vehicle, bounced off of him, back left across 2 lanes scraped the right of another car, and then hit the concrete wall. The driver that came into my lane keep going and my truck looks like a total loss. It's been fun reading this forum, but I think that I'm toast. I'm trying not to feel bad about the love and time that I've put into maintenance, upgrades, repairs, transmissions, body work, and other pride inspired self starter type efforts that I've put into this truck, and just instead remember that it likely saved my life. I will not buy anything less than a full-size. Maybe I'll get lucky and find another one nearly like it.
Very scary and sad to hear. Glad your alive and well enough to come on here and give us an update. Good luck on your next truck and if it’s a gm suv you know where to find us :boti:
 

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