P0734??

[hondarider552]

First issue ive had with this trans, trans was refreshed by Mike about 3 months ago, SC 4/ ML converter, went WOT on my big tune to about 45-50mph, felt like it hit neutral, & locked in 3rd gear, no CEL, no P0700. Had to stop, pull over pulll codes on V2, shut off truck and restart and everything was fine. Read around and maybe NBSU?

Code is Gear 4 ratio error.

 

[Mike L.]

Speed sensor or possible transfer case. We never see 734 codes.

 

[hondarider552]

Pulled whatever TCM tune was in it before, and defuel is turned off. Im going to turn it back on and go from there. I'll call you if anything comes up Mike. Thanks.

 

[SSchmi5519]

Pulled whatever TCM tune was in it before, and defuel is turned off. Im going to turn it back on and go from there. I'll call you if anything comes up Mike. Thanks.

:thumb::thumb::thumb::thumb:

 

[IOWA LLY]

Who turned it off in the first place?

 

[SSchmi5519]

Who turned it off in the first place?

IIRC, and it was a while ago, they couldn't get it to shift right, turned the defuel off and it fixed the problem. This is caused by poorly tuned defuel in the ECM.

 

[hondarider552]

Correct, but this was before I owned the truck. This truck was a customers of where I used to work. I dont know all the details of what happened to the first trans build, so im not going to point fingers.

 

[IOWA LLY]

How long has it been ran with it turned off then?

 

[hondarider552]

Maybe 2 months? About 2500 miles or so. Let me look real quick.

 

[hondarider552]

Defuel was removed at 110,8xx and truck has 112,3xx on it now. Refreshed trans has about 4000 miles on it.

 

[Mike L.]

Not a good idea turning off defuel. It tends to cause tie up's pretty bad.
The history on that trans is; when the motor was pulled out they dropped the trans and broke the bell housing. They welded it back up mis-aligned and took out the pump and the converter because the dowel pins were no longer aligned so they left them out. I replaced the housing, pump, and converter.

 

[SSchmi5519]

Brian's going to bring the truck down here to get everything dialed in. Its going to shift smoother than the butter Mike puts on the sheep... :rofl: :thumb:

 

[Chevy1925]

Pulled whatever TCM tune was in it before, and defuel is turned off. Im going to turn it back on and go from there. I'll call you if anything comes up Mike. Thanks.

Told you to turn that back on a few weeks ago

 

[hondarider552]

Not a good idea turning off defuel. It tends to cause tie up's pretty bad.
The history on that trans is; when the motor was pulled out they dropped the trans and broke the bell housing. They welded it back up mis-aligned and took out the pump and the converter because the dowel pins were no longer aligned so they left them out. I replaced the housing, pump, and converter.

Interesting. Thanks Mike :thumb:

Told you to turn that back on a few weeks ago

I havent driven the truck since we talked untill last night.

 

[BLKLMM]

Brian's going to bring the truck down here to get everything dialed in. Its going to shift smoother than the butter Mike puts on the sheep... :rofl: :thumb:

:spit:

 

[IOWA LLY]

So did turning the de-fuel back on fix it?

 

[hondarider552]

Not sure yet im gunna have steve retune the tcm and look into the torque based fuel table this weekend.

 

[MMLMM]

Who tuned it, I know you know...

/Stirpot

 

[hondarider552]

Well Steve and I have been working on the DSP2 and the TCM tuning for about 2-3 hours now, shifts way better at part throttle and WOT shifting has improved greatly. Messing around with some other small stuff, adjusting for my transferflow tank, TCC lockup speeds, etc. Converter now locks at 47mph from 56mph, trans temps have dropped a bit in the city. 108* outside right now, so everything is hot, but EGT's are down on both tunes on the DSP. Still have some work to do though, my scan tool doesnt want to read main injection pulse, just comes up with a "1" for the value.

Updates to follow. :thumb:

 

[hondarider552]

So did turning the de-fuel back on fix it?

for the most part. Still had to adjust the amount of de-fuel mm3's, but all is good now, shifting like it should. Which reminds me, I need to get a C3 oiler for this trans.