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

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Rocket Man

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they are sold as a separate piece, I had to buy 1 for the denali but I am sure it is a different length because it is a xl.
AND I think I had to get it from the dealer, can't find it in my purchase history online anywhere.
slim chance it could have came from rock auto but I doubt it
I edited the post after finding the part numbers; more like $200 for the longer front pieces, 100 for the shorter back ones. Plus shipping.
 

the_tool_man

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I noticed that, too. It isn't very tight. Interestingly after messing with it last night and getting everything nice and dry overnight, I checked it after my commute in the rain this morning and everything is dry. I may have accidentally fixed it, lol.
No such luck. When I got home there was a small puddle in the back, though much smaller than yesterday. From what I can tell, that gland...boot, whatever you call it, is the source. I'm going to silicone it and see what happens.
 

Grady_Wilson

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I got close when I visited my gg grandparents grave in Lovell a couple of years ago.

I’m heading to Pinedale in a few days.
I go through Farson every time I come up this way.
There used to be an older lady that worked at the gas station in Farson.
She went back to college and finished her degree in her mid 80's.
Super nice lady.
Sadly, she passed a few years ago.
 

Sparksalot

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I go through Farson every time I come up this way.
There used to be an older lady that worked at the gas station in Farson.
She went back to college and finished her degree in her mid 80's.
Super nice lady.
Sadly, she passed a few years ago.
Farson = ice cream!

My dad’s college roommate lives in Centennial. His wife turned me on to Farson.
 

alpha_omega

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With new sticky OEM thermostat and stock fan settings, I was running between 194-203 deg.
This Motorad 174 keeps me at 186-190 (light city commuting, will test more), and consistently opens(fully?) at 188.
I may be dipping to 186 because I removed the jiggler valve and have that 1/8" hole bypass, it really stays at 188 around town until you slow down.
OEM 200k mile thermo was also consistent at 194.
No go on the motorad. Bench test says 196° open temp. I got it to open once at 192°. IMG_1061.jpegIMG_1064.jpegIMG_1066.jpeg
 

Doubeleive

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gm likes to "quiet quit" on some things, gm oe water pumps for instance used to have a lifetime warranty, the thermostat is supplied with a new pump.
now they have a 2 year warranty.
pretty sure melling is there supplier like oil pumps, melling offers a 3 year warranty on non performance pumps, but doesn't sell a thermostat separate
so that leads me to wonder who makes there thermostat..... or who is there supplier.
at any rate I would probably just stick with a oe thermostat, unless you are trying to lower the temp but that's going to come with risk.
so many crap thermostats out there I learned my lesson a long time ago, trying to save $5-10 just leads to headaches and more work

atleast on the k2+ they made the pumps modular, you can replace the actual "pump" for about $40 and you don't have to take the front of the engine apart.
unless the inner gasket blows out.
 

mikez71

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No go on the motorad. Bench test says 196° open temp. I got it to open once at 192°.
Wow, that is unfortunate...
I did not boil any thermostats, because I was too lazy to buy a temperature probe.. .
But my Motorad is definately opening at 188.. (that's when temps first drop, and that's where my temp stays during cruise)
As @j91z28d1 mentioned, maybe I got lucky if they are consistently inconsistent... (If I had determined that I wanted 174 deg, then I would be disappointed)

As a final check, you might look for the temp rating inside the tube.. But assuming it's just inconsistent..
How does Lingenfelter sell these? Or is Motorad selling the rejects?
 

mikez71

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pretty sure melling is there supplier like oil pumps, melling offers a 3 year warranty on non performance pumps, but doesn't sell a thermostat separate
so that leads me to wonder who makes there thermostat..... or who is there supplier.
at any rate I would probably just stick with a oe thermostat, unless you are trying to lower the temp but that's going to come with risk.
I guess I have 3 spare new thermostats..
Melling water pump comes with MotoRad 5945KT / 15608. It's a cheap looking thermostat neck, and a 187 deg MotoRad thermostat.
Which is funny because the temps my "174" opens at, would be perfectly accurate as the 187 deg thermostat..

I spent the extra $35 for an OEM thermo, just to not have it not open until 201-203 degrees at times..
Still agree, most parts I end up going back to stock.

The OEM casting was different from the Melling. Think I might have saved $100 or so. And while the Melling has given me no issues yet, I would go OEM next time probably.
Were I Melling, I wouldn't include that thermostat neck just because it looks bad. A bit of porosity on the sealing surface, hose surface has casting flange ground down whereas stock is machined round full circumference.. I'm sure it will work, but when you hold the OEM next to that one, no way I'm using the Melling(motorad) neck.

IMG_0508.jpeg

IMG_0507.jpeg
 
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Doubeleive

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I guess I have 3 spare new thermostats..
Melling water pump comes with MotoRad 5945KT / 15608. It's a cheap looking thermostat neck, and a 187 deg MotoRad thermostat.
Which is funny because the temps my "174" opens at, would be perfectly accurate as the 187 deg thermostat..

I spent the extra $35 for an OEM thermo, just to not have it not open until 201-203 degrees at times..
Still agree, most parts I end up going back to stock.

The OEM casting was different from the Melling. Think I might have saved $100 or so. And while the Melling has given me no issues yet, I would go OEM next time probably.
Were I Melling, I wouldn't include that thermostat neck just because it looks bad. A bit of porosity on the sealing surface, hose surface has casting flange ground down whereas stock is machined round full circumference.. I'm sure it will work, but when you hold the OEM next to that one, no way I'm using the Melling neck.

View attachment 464370
View attachment 464371
I wouldn't use that housing either, looks rough. good example of poor quality control
 

Scrappycrow

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atleast on the k2+ they made the pumps modular, you can replace the actual "pump" for about $40 and you don't have to take the front of the engine apart.
unless the inner gasket blows out.
Can this arrangement be retrofitted to our GMT900s? I've already got a brand-new OE spare on hand, but it'd be good to know if this would be an option.
 

Doubeleive

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Can this arrangement be retrofitted to our GMT900s? I've already got a brand-new OE spare on hand, but it'd be good to know if this would be an option.
Nooo, there not even close to the same at all.
pop the hood of any k2, you'll see.
at first it looks kinda crazy the way the housing stretches across the front of the engine.
but the pulley comes off and the fins/etc are a separate piece behind it
kpump.JPG

kpump1.JPG
kpump2.JPG
 

mikeyss

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I have been slowly doing my annual OCD type of detail on the Tahoe. It's taking longer than usual due to the heat and I'm still recovering from rotator cuff surgery. The interior is almost done
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My dash is getting pretty bad, I was afraid to keep cleaning it because it was creaking so bad. The center defrost area is really broken, and the crack my the left-hand side of the instrument panel is badly cracked. Surprisingly, the area around the center speaker still looks new.
 

mikeyss

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Unfortunately, the rust bug is attacking the Tahoe, and I had been thinking of selling it and moving on. But after the interior detail, I just can't get rid of it. I love this thing and waited MANY years to find one with the L9H. This is my baby and I can't part ways with it, no matter what. Do you guys think this can be fixed?
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It's only the driver's side. Also both left hand doors are screwed, I'll have to replace them.
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Scrappycrow

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Nooo, there not even close to the same at all.
pop the hood of any k2, you'll see.
at first it looks kinda crazy the way the housing stretches across the front of the engine.
but the pulley comes off and the fins/etc are a separate piece behind it
Dang, that is indeed quite different! Thank you for all the pics of the setup & components.
 

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