4l60e third gear starts

[BlackTAsshole]

I have a 2000 TA and I rebuilt the transmission about 2 years ago, it has about 15k miles on it. I also installed a hughes 2300 stall when it was out and lately i've been having this weird problem i'm hoping someone can help me out with.

Every now and then it wants to take off from third gear. You can manually shift it down to first and back to drive and it works fine afterwards. Other than that the transmission works perfectly. I was reading some and it says could be caused by VSS dropoff from a Hi Stall?

Has anyone else experienced this?

[warriorpluto]

Check wiring to the transmission. I had three sierras with the same problem and a new transmission harness fixed it

[BlackTAsshole]

The harness was replaced when I rebuilt the transmission. The other one basically crumbled when I started plugging in some of the connectors.