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

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Grady_Wilson

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If anybody gives a $hit, I been using these for a few years and they are pretty good for the price. I go at least 6 months per pair. And I beat the hell out of them daily.

I use these and they have held up great in the winter with ice and snow.
Come with one refill.
Replace the blade about every 10 months.

 
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dkad260

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Late to add this as I finished it last week, but with 155K, I smelled a slight coolant odor at a light, then again at another light but nothing after that. Given the mileage and the OE water pump, I figured I would do some prevent/required maintenance.

Looks like there may have been what appears to be the start of a leak into one of the mounting bolt holes.

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So I went ahead and replaced the pump, hoses, T-fittings with Dorman aluminum fittings, OE pump with thermostat, as well as OE oil cooler lines, front main seal and new balancer. I did not use the plastic T- fitting in the pic. I also used the Dorman heater hose which also uses an aluminum fitting.


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Screenshot_20250514_172159_Gallery.jpg
 

j91z28d1

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Didn't Project Farm test that homebrew mixture in one or more comparisons? It never did that well.


I think he did, but like most tests it's not really real life. like didn't he put bolts in threaded clear plastic and then fast rust the bolts with some chemical? or was that someone else.

either way, it's hard to reproduce 10 rusted bolts that took 10 years to get like that so you could get a good test
 

RooTBeeRthe1st

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I think he did, but like most tests it's not really real life. like didn't he put bolts in threaded clear plastic and then fast rust the bolts with some chemical? or was that someone else.

either way, it's hard to reproduce 10 rusted bolts that took 10 years to get like that so you could get a good test
Yeah you mix like salt and peroxide or something
 

j91z28d1

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not really about the 6L80 in these trucks but we are getting to the point of 10 speed swaps being a thing. Just make sure it's "fixed" before the swap, so you don't end up worse off than a rebuilt 6 speed. I did enjoy the rant about the 8 and 10 speed issues. and over all how everything new is pretty bad these days.


I did agree with the take away of find the flaws in your vehicle and upgrade to fix those flaws over just buying new vehicles that haven't been sorted out yet.


I also agree that the new crazy amount of gears in trannys is about trying to lug the engine around at 800 rpm all the time for fuel mileage. 6 feels like enough to me.
 

Scrappycrow

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So I went ahead and replaced the pump, hoses, T-fittings with Dorman aluminum fittings, OE pump with thermostat, as well as OE oil cooler lines, front main seal and new balancer. I did not use the plastic T- fitting in the pic. I also used the Dorman heater hose which also uses an aluminum fitting.

View attachment 457399
What's the brand & part number for that aluminum tee? Thanks in advance!
 

j91z28d1

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wow those are new? only metal ones id seems is the crazy price ones that need like 15 clamps.

I'd buy these.
 

dkad260

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@Scrappycrow Yes, these are the ones. Not any different as far as removal than the plastic ones. For me, I push them in until they stop, reach my fingers back and push in the tabs that are outside of the fitting, then pull back .

I found it easier to release one from the firewall fitting then the rear line in that order install the reverse order rear line then firewall. I removed the driver side fitting before the passenger side fitting.
wow those are new? only metal ones id seems is the crazy price ones that need like 15 clamps.

I'd buy these.
They seem well made, they just don't include the plastic retainer for the rear line so you have to swap that over or buy another one.

Edit to add: the above mentioned about missing the plastic retainer was inaccurate, my apologies I left it since it has been viewed and quoted.
 
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89Suburban

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89Suburban

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Late to add this as I finished it last week, but with 155K, I smelled a slight coolant odor at a light, then again at another light but nothing after that. Given the mileage and the OE water pump, I figured I would do some prevent/required maintenance.

Looks like there may have been what appears to be the start of a leak into one of the mounting bolt holes.

View attachment 457396

View attachment 457395

View attachment 457397

So I went ahead and replaced the pump, hoses, T-fittings with Dorman aluminum fittings, OE pump with thermostat, as well as OE oil cooler lines, front main seal and new balancer. I did not use the plastic T- fitting in the pic. I also used the Dorman heater hose which also uses an aluminum fitting.


View attachment 457398

View attachment 457399
Looks great. This piece I circled is still a known failure point but still you should get many, many miles / years of driving out of it. Very nice work and thanks fort taking the time to share and post with the pics.



Screenshot_20250514_172159_Gallery.jpg
 

89Suburban

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Since we are on this subject. My brother's Silverado p/u has plastic connectors on the heater core I am worried about failing. No rear heat tee's on that truck. Just straight non-tee connectors. One is definitely weeping. I warned him about it a year ago when he bought the truck, and again a month ago. His luck is going to run out. I may try to keep some new pieces on hand JIC. He lives an hour away from me and is always running many miles a day on that rig. I am worried about it failing before I can convince him to change them out.
 

dkad260

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Looks great. This piece I circled is still a known failure point but still you should get many, many miles / years of driving out of it. Very nice work and thanks fort taking the time to share and post with the pics
Thanks.

Is there a hose with a metal coupling avail for what's in the circle? Good to know about the failure point....I thought it was only the "T" fitting.
I am worried about it failing before I can convince him to change them out.
Hopefully you can get him to change it, they are definitely somewhat easy to replace after finally getting around to it. I thought it was going to be more of a pita.
 

j91z28d1

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Since we are on this subject. My brother's Silverado p/u has plastic connectors on the heater core I am worried about failing. No rear heat tee's on that truck. Just straight non-tee connectors. One is definitely weeping. I warned him about it a year ago when he bought the truck, and again a month ago. His luck is going to run out. I may try to keep some new pieces on hand JIC. He lives an hour away from me and is always running many miles a day on that rig. I am worried about it failing before I can convince him to change them out.


not the correct way, but if he's stubborn about it. Just quickly pull the connector off, cut the end off the hose and put it over the aluminum heater outlet. Just get it over the ridge in the aluminum and a clamp behind it.

without needing to T off to the rear heat, there's honestly no need to quick connections there anyways. if you can reach it, probably only that a few mins and not ever waste much coolent.
 

Grady_Wilson

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Since we are on this subject. My brother's Silverado p/u has plastic connectors on the heater core I am worried about failing. No rear heat tee's on that truck. Just straight non-tee connectors. One is definitely weeping. I warned him about it a year ago when he bought the truck, and again a month ago. His luck is going to run out. I may try to keep some new pieces on hand JIC. He lives an hour away from me and is always running many miles a day on that rig. I am worried about it failing before I can convince him to change them out.
The straight metal ones were available before the metal Ts were.
I'd buy those and have them on hand.
If the plastic ones break you're dead in the water.
 

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