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

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Grady_Wilson

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Runfor5

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Ended up acquiring a tune from PCM of NC for the DoD+VVT delete. It is via an HP Tuners file, handy since I already have access to that method. Curious if anyone has used their tune for these purposes and how you liked it?
- Noteworthy points I put on their tune sheet: 91 octane, level 2 "medium" shift firmness (at their recommendation), noted cylinder heads as "stock" despite the beehive springs and aftermarket intake valves + pushrods to go in.

Hoping to wrap up getting the car back together this weekend.
 

Scrappycrow

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noted cylinder heads as "stock" despite the beehive springs and aftermarket intake valves + pushrods to go in.
The spring harmonics and the weights of the springs, retainers, pushrods, and valves would only matter to the tune if you're increasing the rev limiter RPM, and the valves would only affect tuning if their edge profile and/or stem size changed the flow more than a few percent.
 

Charlie207

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Got the headers and y-pipe mocked up on my basement floor, and have some initial thoughts: They recommend four clamps as an optional upgrade, but don't offer a 3.5" band clamp to connect the y-pipe to the first extension, so I had to order one of those separately.

They forgot to include a bung for that downstream O2 sensor on the pipe that runs along the transmission crossmember.... maybe I can find an old sparkplug to jam in there.

The transition diameters from the 3.5" y-pipe to the factory exhaust connector leave a little to be desired. In that 2nd pic you can see the severe step-down from 3.5" to 3", then down to 2.75". I think I can just make it work with 3" back to my existing cat-back system, but I might order a 3.5" to 3" reducer cone to make the transition less abrupt.

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I'm still waiting on the back-ordered spark plug wire fire sleeves, and they say the restock is due on 7/31, so I have time to work on how I'm going to undo those six annoying manifold downpipe to cat. bolts.
 
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PG01

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So the rear was clean inside, no metal to speak of on mag, drove it all day yesterday and today, no leaks on the felpro gasket … yet. Backing plates were a little worse than mine but parkiybrakes were in better shape… go figure …like i said needed it in and its in. I let my daughter take my car just to be sure tahoe is good.
I think while i have the spare out ill scrape and clean up the frame and the rear area and maybe get a new hoist.
But for today its brakes, oil change, trans fluid and belt on my daughters honda.
Kinda tired of playing mechanic, hopefully back to regular programming soon… lol and my buddy just hanging out in garage with me…
image.jpg
 

Rocket Man

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Mine are starting to peel, and I hate them because they stick out.
Mine are just starting I noticed. I suppose it will only get worse so one point for removal. :popcorn:
The only problem I had when I removed mine was the pass side B door was replaced and repainted so behind that strip it was a little discolored but you can barely see it unless you know to look for it. Other than that I don't miss them or the badging one bit.
Kinda what I thought most people feel. One more point for removal.
I kinda like the way they look. :shrug:
I kinda do too tbh but I think I’ll like the look without them also. But one point to keep them.


I’m still deciding but I’m pretty sure that the look I’m going for wont look right with them on so it’s a 90% chance they’re coming off. I suppose it’s going to eat up an eraser wheel or two, that looks like a lot of adhesive unless they’re just held on with strips of the tape. Anybody done it that can share?
 

Rocket Man

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So the rear was clean inside, no metal to speak of on mag, drove it all day yesterday and today, no leaks on the felpro gasket … yet. Backing plates were a little worse than mine but parkiybrakes were in better shape… go figure …like i said needed it in and its in. I let my daughter take my car just to be sure tahoe is good.
I think while i have the spare out ill scrape and clean up the frame and the rear area and maybe get a new hoist.
But for today its brakes, oil change, trans fluid and belt on my daughters honda.
Kinda tired of playing mechanic, hopefully back to regular programming soon… lol and my buddy just hanging out in garage with me…View attachment 461915
Good helper dog. Mines chillin right now, we picked up some Koi at the airport early this morning so he’s napping.
image.jpg
 

89Suburban

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So the rear was clean inside, no metal to speak of on mag, drove it all day yesterday and today, no leaks on the felpro gasket … yet. Backing plates were a little worse than mine but parkiybrakes were in better shape… go figure …like i said needed it in and its in. I let my daughter take my car just to be sure tahoe is good.
I think while i have the spare out ill scrape and clean up the frame and the rear area and maybe get a new hoist.
But for today its brakes, oil change, trans fluid and belt on my daughters honda.
Kinda tired of playing mechanic, hopefully back to regular programming soon… lol and my buddy just hanging out in garage with me…View attachment 461915


I have this one on mine and did the same thing when the spare was out. My frame is pretty rust free I just painted it all under there while I had access.

 

PG01

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I have this one on mine and did the same thing when the spare was out. My frame is pretty rust free I just painted it all under there while I had access.

Would love to bring it somewhere an just have them dry ice/sandblast/scrape the entire bottom of the truck and then ill por15 it something… meh wishful thinking.
Ty for the link
 

89Suburban

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Would love to bring it somewhere an just have them dry ice/sandblast/scrape the entire bottom of the truck and then ill por15 it something… meh wishful thinking.
Ty for the link
Hopefully that bolt aint frozen on ya.
 

Grady_Wilson

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Mine are just starting I noticed. I suppose it will only get worse so one point for removal. :popcorn:

Kinda what I thought most people feel. One more point for removal.

I kinda do too tbh but I think I’ll like the look without them also. But one point to keep them.


I’m still deciding but I’m pretty sure that the look I’m going for wont look right with them on so it’s a 90% chance they’re coming off. I suppose it’s going to eat up an eraser wheel or two, that looks like a lot of adhesive unless they’re just held on with strips of the tape. Anybody done it that can share?
From what I've seen it is double sided tape.
 

Rocket Man

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From what I've seen it is double sided tape.
yeah like the other stuff I just removed but there’s a lot of surface area with these so I’m hoping the entire backside isn’t covered in tape, but just the perimeters. I have plenty of fishing line and I can buy another eraser wheel if I need it.
 

PG01

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yeah like the other stuff I just removed but there’s a lot of surface area with these so I’m hoping the entire backside isn’t covered in tape, but just the perimeters. I have plenty of fishing line and I can buy another eraser wheel if I need it.
Methinks its only 2 strip of ds tape….
 

89Suburban

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yeah like the other stuff I just removed but there’s a lot of surface area with these so I’m hoping the entire backside isn’t covered in tape, but just the perimeters. I have plenty of fishing line and I can buy another eraser wheel if I need it.
It's not bad at all just a little extra elbow work you be fine.
 

Grady_Wilson

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yeah like the other stuff I just removed but there’s a lot of surface area with these so I’m hoping the entire backside isn’t covered in tape, but just the perimeters. I have plenty of fishing line and I can buy another eraser wheel if I need it.
The pieces I've seen come off it was just tape alone the outside edges.
 

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