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

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Charlie207

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man I see so many posts of automatic trannys going bad left and right. I thought the 4l60 had a bad rep when used hard, all these newer 6 and 10 speeds seem to lunch themselves at $8-10k a pop every 150k miles less. at least the poor. 4l60 lasted forever if just daily driven.

what happened to drivetrain reliability the last few generations across all these automakers.
My 6L80 is at 180k, and seems to be fine. Replacing the weak-link of a torque converter with a better version (6L90 units work) seems to be the key to longevity.
 

j91z28d1

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My 6L80 is at 180k, and seems to be fine. Replacing the weak-link of a torque converter with a better version (6L90 units work) seems to be the key to longevity.


that definitely seems to help, but it sure feels like there's more going on with them reading all these posts.
 

j91z28d1

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My 6L80 is at 180k, and seems to be fine. Replacing the weak-link of a torque converter with a better version (6L90 units work) seems to be the key to longevity.

hey I forget, where you looking for a wiring diagram for your abs module?
 
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man I see so many posts of automatic trannys going bad left and right. I thought the 4l60 had a bad rep when used hard, all these newer 6 and 10 speeds seem to lunch themselves at $8-10k a pop every 150k miles less. at least the poor. 4l60 lasted forever if just daily driven.

what happened to drivetrain reliability the last few generations across all these automakers.
They're all missing a third pedal, that's what's wrong with them
 

j91z28d1

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They're all missing a third pedal, that's what's wrong with them


true story.

manual swap everything lol.

I just saw a clip of a chic driving a manual 7.3 diesel truck, I'm no Ford guy and I pretty much despise working on diesels but man I bet that old truck would go a million miles on just oil changes and maybe a fuel control module ever 300k haha.


we're about to lose our old 7.3 wrecker at work being replaced by a brand new $150k plus thing that will probably be junk. old one is perfect but aged out by the bean counters that need the turn over for depreciation loss numbers to avoid taxes. Will be sold off for scrap metal prices.
 

Tonyrodz

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true story.

manual swap everything lol.

I just saw a clip of a chic driving a manual 7.3 diesel truck, I'm no Ford guy and I pretty much despise working on diesels but man I bet that old truck would go a million miles on just oil changes and maybe a fuel control module ever 300k haha.


we're about to lose our old 7.3 wrecker at work being replaced by a brand new $150k plus thing that will probably be junk. old one is perfect but aged out by the bean counters that need the turn over for depreciation loss numbers to avoid taxes. Will be sold off for scrap metal prices.
Companies do the same thing with old people/employees.
 

Charlie207

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So.,.. the v3 tune from BBP was problematic. Hard starts, stalling, engine dying when tapping the brake pedal. Made driving around town in traffic wicked exciting.

I reverted back to the v2 tune, and messaged them about some of the symptoms. They had mentioned that there was a Bank 1 (mechanical) fueling issue, so last night I pulled out the intake manifold to clean everything. I pulled out the four driver's side injectors and did the home-brew injector cleaning. They all looked clean as could be (zero issues with fueling when the 5.3 was installed) and the engine still ran like crap after it was all reinstalled. The V2 fixed the hard start/stalling issue.

I did end up ordering new 50lb injectors to have on hand. LSXeleration had decent prices and a Veteran discount. This was the part# BBP recommended if I were to upgrade: https://www.lsxceleration.com/delphi-gm-50lb-hr-ls-truck-flex-fuel-injectors-12613412-8/
 
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Charlie207

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hey I forget, where you looking for a wiring diagram for your abs module?
Yes. My new oscilloscope arrived in the mail yesterday, and this weekend I'm going to start digging into the loom to see if there are any crushed, cut, melted wires.

I am starting to suspect that I might have damaged some section of the engine loom while pulling out the 5.3 or when I installed the 6.0, and this lines up (at least in theory) with how I had zero issues when I parked the Yukon, but lots of issues as soon as I fired it up with the new engine.
 

j91z28d1

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Companies do the same thing with old people/employees.


to be fair no one ever leaves here. we've got 70s hire dates still active in the system. I can only guess they are filling up 1st shift lead spots in the retirement home stations getting really good at making coffee and wandering around aimlessly or watching deep conspiracy theory youtube channels. most haven't even had a tool box at work in 30 years.

but I do have a weird job, so eh.
 

j91z28d1

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Yes. My new oscilloscope arrived in the mail yesterday, and this weekend I'm going to start digging into the loom to see if there are any crushed, cut, melted wires.

I am starting to suspect that I might have damaged some section of the engine loom while pulling out the 5.3 or when I installed the 6.0, and this lines up (at least in theory) with how I had zero issues when I parked the Yukon, but lots of issues as soon as I fired it up with the new engine.


I guessing you don't have JD9 rpo code. this is what I get for a. 2014 slt with a 5.3. let me know if it's to blurry to read. it looks kinda blah on my phone zoomed in.
 

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