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

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89Suburban

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Yeah, but the lowest it's ever gone has been 12.5 previously.
It shouldn't ever regulate lower than that. And in my opinion, since it's literally just for fuel savings, I'd be happy if I could program it to push 13.5 all the time.
I did an experiment once and removed the sensor from the POS cable that controls that regulation for about a week. It worked. But on longer road trips it seemed to create a slight burnt electrical smell from under the hood from the constant high charging and it freaked me out so I put it back on and left it like it was.
 

Charlie207

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Put some penetrating oil on those lines.
there are little O-rings that seal against the tube.
Wiggle them and twist them, if possible, to get them loose.

When reinstalling, I put a small amount of oil or even light grease on the tube end to help it slide in.
I bet it's slightly crooked and applying pressure.


bolt on the side of the block near the front holds it...

Unbolt/loosen it and you might get some more wiggle room.

And I removed and reinstalled my engine oil cooler lines with the front axle out of there.
I haven't tried with the front axle in.

I have no issue unplugging the lines from either the TOC or the radiator.

It's a routing issue. I can't get the L-shaped hardline backed out of the small cutout between the bumper and radiator support.

The videos I watched for reference didn't show how to remove them.
 

the_tool_man

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The dupli-color spray paint I used to paint my D-pillar appliques didn't even last a year before oxidizing. I called a car painter buddy of mine who told me how much it would cost to properly paint them. I looked on eBay and found a used pair already painted my color for less.
20220625_085029.jpg
Big improvement, and should hold up better in the SC solar beat down.
20220625_090036.jpg

Lesson learned. OEM beats aftermarket (except for headlights, lol). Unfortunately I also discovered that my Eagle Eyes fully-lit CHMSL is cracked. FML.
 

Doubeleive

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I have no issue unplugging the lines from either the TOC or the radiator.

It's a routing issue. I can't get the L-shaped hardline backed out of the small cutout between the bumper and radiator support.

The videos I watched for reference didn't show how to remove them.
those lines shouldn't be between the bumper and radiator, you must be trying to do the power steering cooler lines?
 

Doubeleive

Wes
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The hard line on the right (that's the transmission cool I'm referring to) won't go out of the hole my booger-picker is pointing towards.

View attachment 373725
gotcha, 1 of those should only go to the radiator, but honestly not sure how the other one gets fished in & out of there, must be a way
 

Charlie207

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Here's another angle of the routing. You can see the new line that connects the transmission cooler fitting from the radiator to the auxiliary TOC. Some dumb GM oxygen-stealing mouth-breathing smooth-brained dork designed the dumbest thing for this system.

ovgmSa9.jpg
 

RooTBeeRthe1st

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it's been my experience when a battery starts getting that low then it's getting weak and time for a new one. same when the voltage starts going all over the place more than normal. A change in the weather will usually make it happen. how old is it?
Well, with the engine running I would assume that it would always be trying to maintain at least 12.5, but my yellow top is around 3 years old I think, and my die hard is maybe 2 years old, and I know it's starting to fail.
But I have both of them hooked up.
 

Doubeleive

Wes
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Well, with the engine running I would assume that it would always be trying to maintain at least 12.5, but my yellow top is around 3 years old I think, and my die hard is maybe 2 years old, and I know it's starting to fail.
But I have both of them hooked up.
I have been thru a few set's of the odyssey's and they never last beyond 3 years or they start to die right after the 3yrs warranty is up, I switched to the interstate AGM a year ago or so but I expect they will last about the same time at least the price is better about $160 compared to the odyssey's at $300+
it's the heat here that kills them mostly.
 

Doubeleive

Wes
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Here's another angle of the routing. You can see the new line that connects the transmission cooler fitting from the radiator to the auxiliary TOC. Some dumb GM oxygen-stealing mouth-breathing smooth-brained dork designed the dumbest thing for this system.

View attachment 373745
I would get the lines all loose from the clips and fittings and start wiggling. the rubber part will give you some room to move stuff any direction
 

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