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

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Geotrash

Dave
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Got home safely yesterday evening and parked the camper in front of the house. Unhooked the hitch ball and went to shift into drive to pull away. Got as far as reverse and the shifter linkage on the transmission slipped off. Bushing failed. Terrible design, as many of you know. I'm barrel-chested so getting under there was a little uncomfortable, but I was able to get it shifted into park. I had a kit from bushingfix.com on hand because I knew it would eventually happen, but it's a POS so I ended up buying a Dorman clone of the original design. I think. Hard to tell which one is the correct one. Anyway, the original lasted 132K so I'll roll with it for now.

This is the one I got from Autozone's "help" section yesterday. Rock Auto says it's the right one, so we'll see.


Update: the bushing went on easy peasy. I let it sit in some hot water first to soften it and then installed it into the eye of the cable end first. I used a small screwdriver to make sure the whole lip of the bushing was through the eye and sitting properly in the groove. Then I used a pair of Channel-Locks to press the eye with the bushing onto the shaft of the shift lever on the transmission. Ran the shifter through its range of motion a few times and it seems solid.
 
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Just Fishing

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About 7000 with full water tank, storage compartments and cupboards, according to my cat scale ticket. But usually we don’t roll with a full tank so 6500 or so. We love it.

I assume you have the 6.2?
How does it do going up canyon roads?

We have some pretty steep ones around here, most of the lake type places go up to like a 6%, and that's with a 65mph speed limit.
My old S10 with it's 4.3l could barely do 55mph without anything being towed behind it. :jester:
Add the "big" boat and that's closer to 45-50mph and keeping the rpm right around 4-5k. lol


The Tahoe with the new engine can pretty much do it at 65mph hardly struggling w/o anything in tow.
I haven't towed anything up that canyon yet in the Tahoe, with it making its own anti-seize shortly after I bought it and all. :violin2:


I can't wait to see how it does with the boat, but fully loaded w/trailer that thing should only be right around 2,000-2600lbs.
Knowing I have roughly 600-700lbs of aluminum hull + plywood, fuel, equipment, glass, and a 400lb engine.


:hmmm2:


Now if i could get the wife to use a bucket/freshly dug hole to do her business in.
Then I'll get into overlanding more... :smh: ;)
 

Geotrash

Dave
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I assume you have the 6.2?
How does it do going up canyon roads?
Yes, I do. With a Stage 2 truck cam from Cam Motion and a BB tune. It does really well on the steeps pulling the camper. It'll hold 55-60 in 3rd on a 7% grade. I could go faster but don't care to push it any harder. Holding 65 in 4th on a 6% grade should be no problem.
 

Just Fishing

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I watch a lot of youtube, especially Richard at Precision Transmission. Check out this new short video, I never knew about how the top plate on the rear planet will hide metal, and that there is a better design off this plate to help cool the pinions too


Yeah, I saw those when I did my 6l80
when a transmission gets really nasty, trash gets trapped behind that plate.
Sonnax advertises it as just a like oem replacement, but you have to destroy it to get it off.
It sure is pretty all reinstalled on the back of the planet.

he also needs to stop aligning that hole in the back of the case with the hole in the bushing.
Lube pressure feed comes from inside of the output shaft.
OEM that hole is offset away from that hole/pass through in the case.
My research showed that Lube should bleed out the sides of the bushing, then the pass through is so the seal/shaft can be lubricated and then pass back through into the case.

Him lining that thing up allows pressurized oil to escape from the middle of the bearing surface.

(There are a few youtube videos out there covering the rear case bushing in the 6l80/90)

He has a bushing install video that really made me scratch my head on that subject.
Me detailing the exact position of each bushing, including where the dimples and spirals sit.
I coped the original position exactly on each bushing. :cool:

That said, I'm just a guy that has done a total of "1" of these.
but i also researched the fk out of it.
 

Just Fishing

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And i got an alignment today, post front and rear shocks, upper control arms, and lower ball joints.
2in leveler installed as part of the task.

The tahoe looks so much better now, and i can now change my oil w/o breaking out the jack and jack stands. :cool:
 

Doubeleive

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I assume you have the 6.2?
How does it do going up canyon roads?

We have some pretty steep ones around here, most of the lake type places go up to like a 6%, and that's with a 65mph speed limit.
My old S10 with it's 4.3l could barely do 55mph without anything being towed behind it. :jester:
Add the "big" boat and that's closer to 45-50mph and keeping the rpm right around 4-5k. lol


The Tahoe with the new engine can pretty much do it at 65mph hardly struggling w/o anything in tow.
I haven't towed anything up that canyon yet in the Tahoe, with it making its own anti-seize shortly after I bought it and all. :violin2:


I can't wait to see how it does with the boat, but fully loaded w/trailer that thing should only be right around 2,000-2600lbs.
Knowing I have roughly 600-700lbs of aluminum hull + plywood, fuel, equipment, glass, and a 400lb engine.


:hmmm2:


Now if i could get the wife to use a bucket/freshly dug hole to do her business in.
Then I'll get into overlanding more... :smh: ;)
the 6.2 6l80 will do 90+ up a grade like that not towing anything other than fat butts, she will get warmed up if running that for a extended period
 

Sparksalot

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And i got an alignment today, post front and rear shocks, upper control arms, and lower ball joints.
2in leveler installed as part of the task.

The tahoe looks so much better now, and i can now change my oil w/o breaking out the jack and jack stands. :cool:
I feel your pain on the jacking up. Even with the air dam removed on thecopcar, I can’t really get underneath. Thethirdtwin is so much nicer in that respect.
 

Sparksalot

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I assume you have the 6.2?
How does it do going up canyon roads?

We have some pretty steep ones around here, most of the lake type places go up to like a 6%, and that's with a 65mph speed limit.
My old S10 with it's 4.3l could barely do 55mph without anything being towed behind it. :jester:
Add the "big" boat and that's closer to 45-50mph and keeping the rpm right around 4-5k. lol


The Tahoe with the new engine can pretty much do it at 65mph hardly struggling w/o anything in tow.
I haven't towed anything up that canyon yet in the Tahoe, with it making its own anti-seize shortly after I bought it and all. :violin2:


I can't wait to see how it does with the boat, but fully loaded w/trailer that thing should only be right around 2,000-2600lbs.
Knowing I have roughly 600-700lbs of aluminum hull + plywood, fuel, equipment, glass, and a 400lb engine.


:hmmm2:


Now if i could get the wife to use a bucket/freshly dug hole to do her business in.
Then I'll get into overlanding more... :smh: ;)
I’ve been thinking about this one for that possibility.


 

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