Hey guys,

I've had my 2007 GMC Sierra 1500 Vmax for a couple years now and love it but now I have a reoccurring issue that I can't figure out and hopefully someone here knows exactly what might be wrong.

The Issue:

This will happen randomly at any given time. I'll be driving along just fine and everything will be normal. I'll come to a stop, go to take off and the trans wont shift out of first and the speedo wont move off of 0 mph.

To fix it I have to pull over and stop, shift to neutral then back into drive and everything is just fine after that until the next random occurrence.


Does anyone have any idea what this could be? When the trans does finally shift it doesn't slip or shift hard at all. No clunking, no burning smell, no nothing. I'm a bit baffled.

Thanks for the help in advance!

 

The pcm is not seeing a VSS input from the speed sensor. Check the connector and wiring on the rear of the transfer case if you are a 4wd or on the tailhousing if you are a 2wd. Should have a code stored in the tcm have a tech or shop scan the tcm and see what codes it has in it.
May just be a speed sensor failing as well codes are what you need to diag properly without throwing parts at it.

 

Thank you!