Just finished swapping a 2008 6.0 w/ 4L70E into my 04 Silverado using the Lingenfelter reluctor module plus my stock 04 computer and harness motor stayed awesome but the transmission will not shift beyond 1st gear simply neutralizes after it shifts I also noticed my speedo is not working. We already confirmed that the tranny is good by shifting it using the tech2. Already checked fuses, cleaned and confirmed all wires and connectors are good.

Running out of ideas NEED HELP!!!

 

Assuming you got this from a trailblazer ss??

The tbss uses a TCM to control the tranny and has different speed sensors..As far as i know its not a direct swap..

 

It's off a SILVERADO V-MAX and it does have its own TCM but my 04 should still shift it.

 

If its not shifting and no speedo, then it's not seeing a VSS. I'd start there.

 

We know that The VSS is not sending a signal and that's more than likely why the tranny is not working, we've been trouble shooting the VSS SIG with non luck

 

There is a extra speed sensor in the newer transmissions...

 

We are aware of that sensor it will just be along for the ride, my 04 will not read and or need it.

 

Ok, just throwing it out there in case you didnt know. I assume you traced the harness back to check for shorts in the VSS harness?

 

That's what we're checking this after noon, just keep thinking everything was working fine before this swap.

 

ALOT can happen with an engine and transmission swap...trust me, I spent a month trying to figure out why my AC compressor would not work sometimes.