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

[ivin74]

I’m almost afraid to jinx myself but I think I fixed my trans without touching a wrench. Many of you might know it’s been going into limp mode for the last 6 weeks or more and throwing DTC P0785 for the 3-2 downshift solenoid. I have been trying everything I could think of including replacing that solenoid and a bunch of other stuff. I have the internal wiring harness and all the internal electronics ready to install. My trans builder told me they’d like to see what happens if I disable that code- and told me their builds don’t even use that solenoid. I think they told me it might be setting the code because of my high stall. I bought HP Tuners and figured out how to set that code to not report (thanks @randeez and @Dantheman1540 ) and flashed that tune, and I just finished a long drive- it’s still shifting fine. I will have to do more testing but it looks like that code was causing the PCM to put the trans in limp mode. Wish me luck tomorrow.

That's great news, I bet you are glad that nightmare is over.

 

[Bigkevschopshop]

I’m almost afraid to jinx myself but I think I fixed my trans without touching a wrench. Many of you might know it’s been going into limp mode for the last 6 weeks or more and throwing DTC P0785 for the 3-2 downshift solenoid. I have been trying everything I could think of including replacing that solenoid and a bunch of other stuff. I have the internal wiring harness and all the internal electronics ready to install. My trans builder told me they’d like to see what happens if I disable that code- and told me their builds don’t even use that solenoid. I think they told me it might be setting the code because of my high stall. I bought HP Tuners and figured out how to set that code to not report (thanks @randeez and @Dantheman1540 ) and flashed that tune, and I just finished a long drive- it’s still shifting fine. I will have to do more testing but it looks like that code was causing the PCM to put the trans in limp mode. Wish me luck tomorrow.

Fingers crossed for you man.

 

[Dantheman1540]

I’m almost afraid to jinx myself but I think I fixed my trans without touching a wrench. Many of you might know it’s been going into limp mode for the last 6 weeks or more and throwing DTC P0785 for the 3-2 downshift solenoid. I have been trying everything I could think of including replacing that solenoid and a bunch of other stuff. I have the internal wiring harness and all the internal electronics ready to install. My trans builder told me they’d like to see what happens if I disable that code- and told me their builds don’t even use that solenoid. I think they told me it might be setting the code because of my high stall. I bought HP Tuners and figured out how to set that code to not report (thanks @randeez and @Dantheman1540 ) and flashed that tune, and I just finished a long drive- it’s still shifting fine. I will have to do more testing but it looks like that code was causing the PCM to put the trans in limp mode. Wish me luck tomorrow.

That's awesome! Long live the Beast

 

[iamdub]

I’m almost afraid to jinx myself but I think I fixed my trans without touching a wrench. Many of you might know it’s been going into limp mode for the last 6 weeks or more and throwing DTC P0785 for the 3-2 downshift solenoid. I have been trying everything I could think of including replacing that solenoid and a bunch of other stuff. I have the internal wiring harness and all the internal electronics ready to install. My trans builder told me they’d like to see what happens if I disable that code- and told me their builds don’t even use that solenoid. I think they told me it might be setting the code because of my high stall. I bought HP Tuners and figured out how to set that code to not report (thanks @randeez and @Dantheman1540 ) and flashed that tune, and I just finished a long drive- it’s still shifting fine. I will have to do more testing but it looks like that code was causing the PCM to put the trans in limp mode. Wish me luck tomorrow.

You could've just had Black Bear turn off that code and saved the $600 on the MPVI and HPT credits.

 

[Tonyrodz]

You could've just had Black Bear turn off that code and saved the $600 on the MPVI and HPT credits.


View attachment 346466

Damn!! Either way, I hope you got it fixed. Good luck!

 

[Rocket Man]

You could've just had Black Bear turn off that code and saved the $600 on the MPVI and HPT credits.


View attachment 346466

Damn!! Either way, I hope you got it fixed. Good luck!

Uh-huh. And wait another 2 weeks to see if that fixed it. I asked Justin to look at my log file and tell me what was going on and he told me the PCM was commanding shifts normally, nothing to see here, it's not the problem. That took a MONTH. 2 weeks for the first log file to sit there waiting for him to look at it, and he says my tune doesn't record trans data so here's a new tune. I installed it the same day, datalogged the same day, and waited another 2 weeks for him to say the PCM isn't the problem. He told me it must be the wiring or something else. At that point I decided it was time for me to look at my own damn data. I was prepared to log and see what was going on but decided to try this first. And now I'll start tuning my vehicles myself which I've always wanted to do anyway. Self-sufficiency has always been my thing. There's a few things I still have to pay others to do but I'm narrowing the list. It's sooo worth the money for the HPT to be able to do it myself. I was about to go all cray cray on BBP. I absolutely HATE waiting.

 

[Rocket Man]

Oh, BTW....It's fixed! I drove around for about an hour this morning all over and it's still shifting fine. I even got into some road rallying with a WRX for awhile. The Beast is back!

 

[Tonyrodz]

Oh, BTW....It's fixed! I drove around for about an hour this morning all over and it's still shifting fine. I even got into some road rallying with a WRX for awhile. The Beast is back!

So who won??

 

[Rocket Man]

So who won??

He got me a couple times, I got him a couple times. I got a big thumbs up. I think he was surprised.

 

[iamdub]

Damn!! Either way, I hope you got it fixed. Good luck!

Uh-huh. And wait another 2 weeks to see if that fixed it. I asked Justin to look at my log file and tell me what was going on and he told me the PCM was commanding shifts normally, nothing to see here, it's not the problem. That took a MONTH. 2 weeks for the first log file to sit there waiting for him to look at it, and he says my tune doesn't record trans data so here's a new tune. I installed it the same day, datalogged the same day, and waited another 2 weeks for him to say the PCM isn't the problem. He told me it must be the wiring or something else. At that point I decided it was time for me to look at my own damn data. I was prepared to log and see what was going on but decided to try this first. And now I'll start tuning my vehicles myself which I've always wanted to do anyway. Self-sufficiency has always been my thing. There's a few things I still have to pay others to do but I'm narrowing the list. It's sooo worth the money for the HPT to be able to do it myself. I was about to go all cray cray on BBP. I absolutely HATE waiting.

Facetiously speaking, I was.

I feel you on waiting. That's why I chose to have mine tuned locally even though I already had the AutoCal. Hell, I'm having to spend my weekend in this Hellish heat swapping a transmission in a FWD go-cart simply because I ran out of waiting time for people to respond.