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

[mattbta]

Drove to my dad's about 25 miles away. AC froze my face off both ways.

He wanted to go pick up some top soil so we put 25 bags in the back. 18 year old Nivomats did their thing and had it leveled out!

On the way back, i realized I've been driving an lsx v8 since i was 18 (42 now) and I don't ever want to be without a v8. Just something about the torque. Puts a smile on my face.

 

[OR VietVet]

Started doing the research for my a/c system rebuild for the front and rear. So many parts to keep the numbers straight about in my head.

 

[RAMurphy]

A dumb question is the one that is not asked, so here we go...
If the Schrader valves are having slow leaks and not ******* (auto-censor LOL can't say p.i.s.s.i.n.g.) out full force... Can Teflon tape be used on the cap to seal the leak?
May not be THE solution for yours, but I would think it might work in some cases where leaks are slow.

 

[RAMurphy]

I didn’t say it was low on refrigerant. I took it in and had it charged because I thought it might be. It was a friend who owns a body shop. He has the equipment so he vacuumed it and charged it but it didn’t help, it’s the same. I’m not sure if the compressor cycles off, I know it turns on and the fans come on. Like I said, I don’t know sh*t about AC. I’ll first try to see if I can troubleshoot with my Tech2 but for the 02’s there isn’t much in the menu under HVAC. Thanks for the suggestions.

Rocket Man, I posted in another thread that I had a very similar issue. Although it was cooling not as well as it should, I did throw some belts. I ignored that fact and the compressor finally catastrophically failed. It sent fine metal shavings everywhere. I agree with latvious on the components to replace and of course the compressor. Do this before the compressor fails. Otherwise your in for a bigger repair or many many hours if you do it yourself. I did the repair myself and it took an entire day to clean out the system before I put it back together and brought it to shop to properly service the system. That was five years ago. Still running strong.

 

[Rocket Man]

Rocket Man, I posted in another thread that I had a very similar issue. Although it was cooling not as well as it should, I did throw some belts. I ignored that fact and the compressor finally catastrophically failed. It sent fine metal shavings everywhere. I agree with latvious on the components to replace and of course the compressor. Do this before the compressor fails. Otherwise your in for a bigger repair or many many hours if you do it yourself. I did the repair myself and it took an entire day to clean out the system before I put it back together and brought it to shop to properly service the system. That was five years ago. Still running strong.

Yep I’m leaning that way. I’m going to try a couple things first before I do though. I haven’t even hooked up the Tech2 yet.

 

[treehan77]

One easy check you can do for a/c problems is shine a black light at the condensation puddle that drips under the truck when the a/c runs. If it glows green, the evaporator core is leaking. See that on the car wizard recently. I would hate to have to that job on these trucks.

 

[MassHoe04]

Time for an oil/filter change yesterday.

NAPA 5/30 Full Synthetic -6 qts.
NAPA Gold 1042 filter

Less than $35!

When I did my hub replacement, I guess I did not wait long enough before checking the oil level. I thought I did. Seemed like the oil should have leveled out by the time I got it back on the ground and started it to move into my normal space in the driveway.

Anyway, the dipstick (not me... the one in the engine) showed almost 3 quarts low! So, in a panic, I added 2 and checked again. It was way over!! Oops.

Rather than try to bleed some oil out the drain, I left it. The engine sounded perfect. I'm sure it will be fine. I ran it high for over three weeks and nothing bad happened. The engine was perfectly OK. It did not explode or start blowing leaks in places it shouldn't.

Here is where the level was (well up into the numbers on the stick) for the last couple of weeks before yesterday's oil change:

 

[Scottydoggs]

Time for an oil/filter change yesterday.

NAPA 5/30 Full Synthetic -6 qts.
NAPA Gold 1042 filter

Less than $35!

When I did my hub replacement, I guess I did not wait long enough before checking the oil level. I thought I did. Seemed like the oil should have leveled out by the time I got it back on the ground and started it to move into my normal space in the driveway.

Anyway, the dipstick (not me... the one in the engine) showed almost 3 quarts low! So, in a panic, I added 2 and checked again. It was way over!! Oops.

Rather than try to bleed some oil out the drain, I left it. The engine sounded perfect. I'm sure it will be fine. I ran it high for over three weeks and nothing bad happened. The engine was perfectly OK. It did not explode or start blowing leaks in places it shouldn't.

Here is where the level was (well up into the numbers on the stick) for the last couple of weeks before yesterday's oil change:
View attachment 377861

that only looks to be a qt over to me. to much oil where you may not feel it, can froth up the oil and cause lower oil pressure and lower hp. less oil actually adds HP.

 

[MassHoe04]

that only looks to be a qt over to me. to much oil where you may not feel it, can froth up the oil and cause lower oil pressure and lower hp. less oil actually adds HP.

I know my gauge is off a little because PO did not align properly when applying cluster decal, but the pressure and power was 100% the same as it ever was. No change in readings at idle or highway RPM from what I normally see. Coming up on 205k miles soon. The engine sounds and runs great!

 

[Tonyrodz]

Took it to the mechanic today, he checked some basic things. Does anyone have any recommendations on a good 6" cone filter? I'd rather it be the dry style. The one in my Volant is so filthy, can't even see through it, plus the rubber on the neck is starting to crack. He also told me he thinks the maf is too close to the box(mounted on it), and too far away from the tb to get a good correct reading to send to the pcm. I've had a soft maf code since the original 6.0/cam swap was done. He thinks it being mounted on the cold air box might be part of the issue. Told me to get a new filter, and to clean the maf really good. If those aren't the problems it may be the pcm has a bad board in it. This kind of makes sense to me. The original tuner told me he couldn't program the pcm in the truck, that it kept losing communication with his laptop. This happens to me all the time. Constantly loses communication with the Tech 2 AND with my scanner. One time I had gotten a bunch of crazy random codes when I plugged in my scanner. So--try cleaning the maf, get a new cone filter, and if that doesn't solve the problem, a new pcm.
So........anyone know of a good 6" dry cone air filter?

 

[Rocket Man]

Took it to the mechanic today, he checked some basic things. Does anyone have any recommendations on a good 6" cone filter? I'd rather it be the dry style. The one in my Volant is so filthy, can't even see through it, plus the rubber on the neck is starting to crack. He also told me he thinks the maf is too close to the box(mounted on it), and too far away from the tb to get a good correct reading to send to the pcm. I've had a soft maf code since the original 6.0/cam swap was done. He thinks it being mounted on the cold air box might be part of the issue. Told me to get a new filter, and to clean the maf really good. If those aren't the problems it may be the pcm has a bad board in it. This kind of makes sense to me. The original tuner told me he couldn't program the pcm in the truck, that it kept losing communication with his laptop. This happens to me all the time. Constantly loses communication with the Tech 2 AND with my scanner. One time I had gotten a bunch of crazy random codes when I plugged in my scanner. So--try cleaning the maf, get a new cone filter, and if that doesn't solve the problem, a new pcm.
So........anyone know of a good 6" dry cone air filter?

Just look for one from a reputable manufacturer, that’s a universal size. Here’s a K&N dry cone.

Dryflow Universal Air Filter - 6"FLG, 7-1/2"B, 5-1/4"T; 6"H

6"FLG, 7-1/2"B, 5-1/4"T; 6"H

www.knfilters.com

 

[Tonyrodz]

Just look for one from a reputable manufacturer, that’s a universal size. Here’s a K&N dry cone.

Dryflow Universal Air Filter - 6"FLG, 7-1/2"B, 5-1/4"T; 6"H

6"FLG, 7-1/2"B, 5-1/4"T; 6"H

www.knfilters.com

Cool, thanks Mark.

 

[DirtDigler]

I have AFE dry filters. Never an issue. I prefer them over K&N

 

[Rocket Man]

Bad pressure switch perhaps? If it's taking refrigerant and not cycling/compressing, it's possible the switch is bad and keeping the compressor from kicking on. It's cheap and easy enough to replace that it might be worth it to fire up the parts cannon before you do something more labor intensive.

So I just got the part I ordered from RA but it’s not right. I looked under refrigerant pressure switch and theres 2 categories- the ones that are compressor mounted and one that says ac system mounted that looked like the one on my accumulator. I ordered that one. Now I see there’s a category called ac clutch switch. And under there are the ones that say accumulator mounted. So I ordered a GM genuine. I just checked the compressor visually snd it’s not cycling on. My Tech2 says the ac pressure is out of range so it won’t allow me to cycle the comp on. Pics attached. I’m hoping it’s the switch. Not sure if “cmp sensor” is compressor sensor but the high to low and low to high read the same, at 816 or something. On the side of the old switch it says on at 40, off at 20 psi.

 

[Rocket Man]

Bad pressure switch perhaps? If it's taking refrigerant and not cycling/compressing, it's possible the switch is bad and keeping the compressor from kicking on. It's cheap and easy enough to replace that it might be worth it to fire up the parts cannon before you do something more labor intensive.

So I just got the part I ordered from RA but it’s not right. I looked under refrigerant pressure switch and theres 2 categories- the ones that are compressor mounted and one that says ac system mounted that looked like the one on my accumulator. I ordered that one. Now I see there’s a category called ac clutch switch. And under there are the ones that say accumulator mounted. So I ordered a GM genuine. I just checked the compressor visually snd it’s not cycling on. My Tech2 says the ac pressure is out of range so it won’t allow me to cycle the comp on. Pics attached. I’m hoping it’s the switch. Not sure if “cmp sensor” is compressor sensor but the high to low and low to high read the same, at 816 or something. On the side of the old switch it says on at 40, off at 20 psi.

Edit: I see from alldatadiy that there’s a low pressure and high pressure switch. The low is on the accumulator and the high is mounted in the compressor and requires evacuating the system. I’ll try the low pressure switch. I feel like I’m fumbling in the dark.

 

[NoReverseYukon]

I had some good luck at the junkyard today - 3 Yukon Denalis.
And 2 still had their instrument cluster.

The 2000-2002 cluster lit up fine on the bench.
I need to figure out how to power up the 2003-2006, but if it tests good I will probably be putting it up for sale here.

 

[Fless]

I had some good luck at the junkyard today - 3 Yukon Denalis.
And 2 still had their instrument cluster. View attachment 377908
The 2000-2002 cluster lit up fine on the bench.
I need to figure out how to power up the 2003-2006, but if it tests good I will probably be putting it up for sale here.

2003-2006 cluster pinout attached.

 

[clandr1]

So I just got the part I ordered from RA but it’s not right. I looked under refrigerant pressure switch and theres 2 categories- the ones that are compressor mounted and one that says ac system mounted that looked like the one on my accumulator. I ordered that one. Now I see there’s a category called ac clutch switch. And under there are the ones that say accumulator mounted. So I ordered a GM genuine. I just checked the compressor visually snd it’s not cycling on. My Tech2 says the ac pressure is out of range so it won’t allow me to cycle the comp on. Pics attached. I’m hoping it’s the switch. Not sure if “cmp sensor” is compressor sensor but the high to low and low to high read the same, at 816 or something. On the side of the old switch it says on at 40, off at 20 psi.

Edit: I see from alldatadiy that there’s a low pressure and high pressure switch. The low is on the accumulator and the high is mounted in the compressor and requires evacuating the system. I’ll try the low pressure switch. I feel like I’m fumbling in the dark.

You could try jumping the plug for the low side switch with a paperclip or something similar to see if it forces the A/C clutch to engage. I probably should have mentioned this sooner... Skip to about 1:30 in the video.

 

[Rocket Man]

You could try jumping the plug for the low side switch with a paperclip or something similar to see if it forces the A/C clutch to engage. I probably should have mentioned this sooner... Skip to about 1:30 in the video.

I’ll try that. Do you know if there’s a way to check the high pressure switch?

 

[clandr1]

I’ll try that. Do you know if there’s a way to check the high pressure switch?

I’m sorry, I don’t