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

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kbuskill

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edit* I'd love for hp tuners to be able to do it. I have it and the ecm is unlocked but there's not much defined in there, very basic stuff. I only really did it for afm disable but I do have a test timing table in it right now too. the ecm on a normal truck kinda runs the show, on a hybrid the hybrid controller runs the show. your throttle pedal request an amount of tq and it decides how much to request from the electric motors, and the how much to ask the ecm for. as of now no one had cracked or even wants to hack the hybrid modules of any car. the tuning would definitely be complicated and almost no one with a hybrid thinks of it as anything more than an appliance. they are just a blender or microwave that sits in the driveway instead of the counter top. the market just isn't there to spend the development money on. which is kinda a shame.. maybe some day with the eray corvettes but even then, corvette guys usually think any mods away from what gm intended are unthinkable.
Thanks for all the info. I didn't realize when I asked the original question that your truck was a Hybrid. That all makes sense. I knew they were a lot different but have no firsthand experience with them.

One thing I never understood is why they used the 6.0 instead of the 4.8. Seems counterintuitive to me.
 

j91z28d1

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Thanks for all the info. I didn't realize when I asked the original question that your truck was a Hybrid. That all makes sense. I knew they were a lot different but have no firsthand experience with them.

One thing I never understood is why they used the 6.0 instead of the 4.8. Seems counterintuitive to me.


only thing I can think of was they didn't have a 4.8 in aluminum already in the parts bin? I do believe there was a aluminum 5.3 at some point thou. but yeah, no idea unless it was a marketing desions. it was sorta marketed as a do all no compromise hybrid, which in 2008 was pretty ahead of its time. I don't believe anything else even tried to make a hybrid of any kind with a tow rating. till the last few years anyways
 

Charlie207

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only thing I can think of was they didn't have a 4.8 in aluminum already in the parts bin? I do believe there was a aluminum 5.3 at some point thou. but yeah, no idea unless it was a marketing desions. it was sorta marketed as a do all no compromise hybrid, which in 2008 was pretty ahead of its time. I don't believe anything else even tried to make a hybrid of any kind with a tow rating. till the last few years anyways
The LC9 was the Gen IV 5.3 w/aluminum block, but it looks like they stopped manufacturing them in 2011.

I imagine they stopped making them because aluminum is expensive, and it made more sense to consolidate towards the 6.2 castings.
 

j91z28d1

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The LC9 was the Gen IV 5.3 w/aluminum block, but it looks like they stopped manufacturing them in 2011.

I imagine they stopped making them because aluminum is expensive, and it made more sense to consolidate towards the 6.2 castings.


yeah, I saw a youtuber putting one in a miata. seemed like a nice little setup.

but you're probably right about cost. Just didn't make sense to the bean counters.
 

Charlie207

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yeah, I saw a youtuber putting one in a miata. seemed like a nice little setup.

but you're probably right about cost. Just didn't make sense to the bean counters.
Is the hybrid 6.0 an aluminum block? If so, it's like 100lbs lighter than the iron block, so that's a lot of weight savings over time/miles.

NM, I see it is an aluminum block. And, it has a higher compression ratio than the older 6.0 engines. Looks like a good motor to swap in to anything, unless there are some weird reasons why it can only work in the hybrid rigs.

 

j91z28d1

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nope, same engine block as far as I know. it's basically an ls2 with a weird valve timing cam shaft which is why it has more compression. I feel like ls swap guys don't know about these. you can can find them from time to time sold super cheap when someone is just over the truck because a dealership/shop told them it's 5k to fix something. or they have already milked them for lots of money and fixed nothing. market place is full of them around here.

I just have to many projects as is, no time or place to work on them, or I'd already bought some local a lady was selling a 08 for parts. listing said she stopped to get gas and it never restarted. towed it home and just dumping it for best offer. if I had time I really wanted to take my tech 2 over and see what happened to it. my guess is a simple contactor in the hybrid battery went out. but who's going to fix it, most shops won't touch them. worst case you got a good used tranny to sell someone and a ls2 to build
 

Sparksalot

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nope, same engine block as far as I know. it's basically an ls2 with a weird valve timing cam shaft which is why it has more compression. I feel like ls swap guys don't know about these. you can can find them from time to time sold super cheap when someone is just over the truck because a dealership/shop told them it's 5k to fix something. or they have already milked them for lots of money and fixed nothing. market place is full of them around here.

I just have to many projects as is, no time or place to work on them, or I'd already bought some local a lady was selling a 08 for parts. listing said she stopped to get gas and it never restarted. towed it home and just dumping it for best offer. if I had time I really wanted to take my tech 2 over and see what happened to it. my guess is a simple contactor in the hybrid battery went out. but who's going to fix it, most shops won't touch them. worst case you got a good used tranny to sell someone and a ls2 to build
Are you talking about the hybrids?
 

Charlie207

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nope, same engine block as far as I know. it's basically an ls2 with a weird valve timing cam shaft which is why it has more compression. I feel like ls swap guys don't know about these. you can can find them from time to time sold super cheap when someone is just over the truck because a dealership/shop told them it's 5k to fix something. or they have already milked them for lots of money and fixed nothing. market place is full of them around here.

I just have to many projects as is, no time or place to work on them, or I'd already bought some local a lady was selling a 08 for parts. listing said she stopped to get gas and it never restarted. towed it home and just dumping it for best offer. if I had time I really wanted to take my tech 2 over and see what happened to it. my guess is a simple contactor in the hybrid battery went out. but who's going to fix it, most shops won't touch them. worst case you got a good used tranny to sell someone and a ls2 to build
It looks like it has flat-top pistons, vs. the dished pistons on my LY6 (and other 6.0s), with cathedral port 243/799 heads & smaller combustion chambers. That'll help increase the compression ratio.
 

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