What did you do to your NBS GMT800 Tahoe/Yukon Today?

[mattbta]

Would it make a difference if you used a pcm from a different year NBS that was non flex fuel? Are the internsl electronics different?

a lot of the eBay folks will program the PCM to your VIN. The one I got wasn’t as I’m flashing a modified version of my stock tune. From what I’ve seen, a P59 (1MB memory, green/blue) is a P59 is a P59 regardless of year but I’m not an expert. Fairly sure a non-flex of same year uses the same service number hardware and OS but lacks the flex tuning calibration. These are the cals from mine.

 

[Tonyrodz]

a lot of the eBay folks will program the PCM to your VIN. The one I got wasn’t as I’m flashing a modified version of my stock tune. From what I’ve seen, a P59 (1MB memory, green/blue) is a P59 is a P59 regardless of year but I’m not an expert. Fairly sure a non-flex of same year uses the same service number hardware and OS but lacks the flex tuning calibration. These are the cals from mine.View attachment 389168

I'm not computer guy, but I'd think the internal electronics would be the same, except maybe for pins--like when adding electric fans to an 03 down you'll need to add 2 wires(pins).

 

[mattbta]

I'm not computer guy, but I'd think the internal electronics would be the same, except maybe for pins--like when adding electric fans to an 03 down you'll need to add 2 wires(pins).

Right, need to install the pins on each pcm connector from the fan harness I got.

 

[Fless]

a lot of the eBay folks will program the PCM to your VIN. The one I got wasn’t as I’m flashing a modified version of my stock tune. From what I’ve seen, a P59 (1MB memory, green/blue) is a P59 is a P59 regardless of year but I’m not an expert. Fairly sure a non-flex of same year uses the same service number hardware and OS but lacks the flex tuning calibration. These are the cals from mine.

View attachment 389168

My 2004 L59 has more updated calibrations than those; isn't yours the same truck? I used a standalone WinXP laptop and TIS2000 to update mine to the latest in early 2001. Not sure it makes any difference but you'd have to look at the calibration details to see.

Mine with current calibrations highlighted green:

 

[Rocket Man]

The rear end all depends on how the trans is tuned and how well your truck hooks. I blew up a 10 bolt in my truck with stock trans and stock 5.3 with an LS3 cam. Sheared the ring gear bolts surprisingly enough, never seen anything like it. 500 miles from home no less.

Building a 9.5 14 bolt for it next time.

I’m running a 10 bolt in my blown/ cammed AWD 6.0 ‘02 Denali with the TA Performance girdle. I did shear the output shaft on my Performabuilt level 3 4l60 due to the servo passages being plugged with RTV from the pan gasket ( my fault) yet my rear end has never had an issue. The trans was hitting super hard during the 1-2 shift due to the servo issues thus the twisted output shaft. My point is the 10 bolts will hold more than you think if the bearing mounts are braced with a girdle. If you blew one up with a cammed 5.3 something was already wrong with it imo.

 

[mattbta]

My 2004 L59 has more updated calibrations than those; isn't yours the same truck? I used a standalone WinXP laptop and TIS2000 to update mine to the latest in early 2001. Not sure it makes any difference but you'd have to look at the calibration details to see.

Mine with current calibrations highlighted green:

View attachment 389176

Yeah, there are a few updates I considered flashing but at the time I looked, there wasn’t an available XDF file for those OS which would force me into HPTuners or EFILive to turn on the fans. I may end up having to anyway, but so far, I’m only into it for the cost of the spare PCM ($65) and the bench harness ($25). The Nano is a wash because I can use it for tech2win diagnoses.

 

[Alex_M]

I’m running a 10 bolt in my blown/ cammed AWD 6.0 ‘02 Denali with the TA Performance girdle. I did shear the output shaft on my Performabuilt level 3 4l60 due to the servo passages being plugged with RTV from the pan gasket ( my fault) yet my rear end has never had an issue. The trans was hitting super hard during the 1-2 shift due to the servo issues thus the twisted output shaft. My point is the 10 bolts will hold more than you think if the bearing mounts are braced with a girdle. If you blew one up with a cammed 5.3 something was already wrong with it imo.

AWD takes a lot of load off the rear end as well. I agree, 10 bolt is a great rear end, but abuse over time adds up. Especially in a heavy truck always loaded down.

 

[mattbta]

Noticed one side of the footwell lights I added didn't seem as bright as when initially installed. Compared it to pictures I took and indeed was much dimmer. Only change in recent months was making the wiring more permanent than just sticking a spade connector into the MBEC. Almost forgot troubleshooting 101 - swapped the dim bulb with the bright one from the other side and it followed the bulb. These were jdm-a-star 194's and I replaced with auxito. Now brightness restored on both sides. Attempted to put more of the auxito in the license plate spots, but they're just a tad too long.

Also ordered auxito reverse LED's to replace the Sylvania Zevo I had in there as they were never _very_ bright. These seem much improved!

 

[Rocket Man]

Noticed one side of the footwell lights I added didn't seem as bright as when initially installed. Compared it to pictures I took and indeed was much dimmer. Only change in recent months was making the wiring more permanent than just sticking a spade connector into the MBEC. Almost forgot troubleshooting 101 - swapped the dim bulb with the bright one from the other side and it followed the bulb. These were jdm-a-star 194's and I replaced with auxito. Now brightness restored on both sides. Attempted to put more of the auxito in the license plate spots, but they're just a tad too long.

Also ordered auxito reverse LED's to replace the Sylvania Zevo I had in there as they were never _very_ bright. These seem much improved!

It’s weird, these led bulbs are supposed to last like 20 years and yet I get some that just quit way early. I’ve been doing a full led conversion on my house which is way more expensive than my trucks I found out, especially when finding ones that are compatible with my new smart dimmer system. My front porch light I’m running one from GE that has a dawn-to-dusk sensor and it quit after 6 months. I get it with a vehicle, with all the bouncing around but I feel if they don’t move they should last about forever. Arrrggghhh.

 

[latvius]

It’s weird, these led bulbs are supposed to last like 20 years and yet I get some that just quit way early. I’ve been doing a full led conversion on my house which is way more expensive than my trucks I found out, especially when finding ones that are compatible with my new smart dimmer system. My front porch light I’m running one from GE that has a dawn-to-dusk sensor and it quit after 6 months. I get it with a vehicle, with all the bouncing around but I feel if they don’t move they should last about forever. Arrrggghhh.

I gave up on dawn to dusk a while back I use a timer to replace the switch.

https://www.amazon.com/gp/product/B01KG712PI/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

I don't know anything about smart systems but I've installed this switch about 3 places and it works well for me.