e38 4l80 swap 07 silverado cant get speedo to work???

[b18cls1]

cannot get speedo on dash to work, the trans will shift so it has to be getting some vss just cant see where, vss shows zero and log shows 0

ive attached tune from ecm and tcm

thanks

[gmh308]

What trans was in before the 4L80 went in?

[b18cls1]

4l60

[ScarabEpic22]

Need to flash an 80E OS into the TCM or re-pin the harness so you can properly run the 80E with the 60E OS. Have you tried getting the converter to lockup? Id put money on it not locking until you get the OS swapped or repinned.

[b18cls1]

it has a 80e tune in the t42 and the truck has the speartech harness, no need to pin since its a tcm not a 512k pcm from what i understand.

[joecar]

Do the TCM pinouts for 4L60E and 4L80E look identical...?

Check wire continuity between the VSS sensor and the TCM.

[gmh308]

So what is this "swap"? A 4L80 into an 07 Silverado or an 07 Silverado powertrain into something else.

The ECM tune you have runs speedo over CAN from TCM or ABS via BCM normally. Did the tune come from Speartech as well as the harness.

Difficult to home in on your problem without all the details bud.

[joecar]

Hi Ian,

Is the ECM or IPC expecting data from a specific controller id, and did the segment swap cause the controller id to change...?

[gmh308]

Hi Ian,

Is the ECM or IPC expecting data from a specific controller id, and did the segment swap cause the controller id to change...?

Yes Joe, very likely if it is what it often proves to be, the speed signal is sourced from the ABS unit and is routed through the BCM to the IPC. HS CAN > LS CAN via BCM. The VSS PID does not show as it is not supplied by the ECM. But hard to know without more details on what the swap components are and where they came from. It may simply be a continuity issue as you point out but I looked at the ECM tune and it is a "BCM speedo source" (my words) tune...but nothing is ever exact with GM and the speedo stuff :) (as Ross and Paul have often pointed out),

Cheerz!

[b18cls1]

it is a 07 silverado, had a 5.3 and 4l60 in it, not swapped into anything

built 440lsx with nitrous and 4l80 in it now

harness is from speartech

they offer no tuning support

when connected to the tcm with a modis you can see speed and rpm ect, nothing on dash works tho.

the wiring part seems to be intact. if we get the tcm programed at a dealer with a 4l80e tune for a t42 will it work on the gmlan to communicate with the ecm??

thanks

[MN C5]

The Speedo, BCM & TCM need to have compatible OS's. I believe the Speedo gets its signal from the BCM, I had it a bit easier swapping a 6L90 because I was able to use a factory harness from a HD2500 that came with the 6L90.

And even if the connectors are the same it doesn't mean that the leads back to the BCM have the right connections. My guess is if you trace the wiring back to the BCM from the speedo you'll find the issue in the wiring or OS's.

Good Luck

[gmh308]

it is a 07 silverado, had a 5.3 and 4l60 in it, not swapped into anything

built 440lsx with nitrous and 4l80 in it now

harness is from speartech

they offer no tuning support

when connected to the tcm with a modis you can see speed and rpm ect, nothing on dash works tho.

the wiring part seems to be intact. if we get the tcm programed at a dealer with a 4l80e tune for a t42 will it work on the gmlan to communicate with the ecm??

thanks

Ok gotcha now. If you get a 4L80 tune into the T42 that sends speedo on the GMLAN it "might" work. Depends on whether the TCM tune is compatible with the ECM where it needs to be. Other choice is I can send you a tune that expects the speedo input direct and routes the VSS PID correctly, to try out.

[b18cls1]

anythings worth a try

[gmh308]

anythings worth a try

Ok...if you are interested PM your email address through.

[b18cls1]

pmed

[DURAtotheMAX]

IIRC the only GMT-900 application that used a 4L80 from the factory was the 07-08 2500 suburban. See if you can find a T42 calibration from an 07-08 suburban 2500 and I bet that will work. :)

[DURAtotheMAX]

any updates?