ok.. took our gc sxt in monday for that 2nd to 1st downshift bump.. this is the second time.. first the flashed and upgraded the software in the tcm.. no change.. then they replaced the input shaft speed sensor.. and still no change.. any body got suggestions... please.. i got 400 miles till the warranty runs out...

 

Take the the van back to the dealer, and have them look up case number 999926034 on star online and tell them that you are having a harsh down shift/ bump. The fix is a valve body.

 

a quick thing to fix many shift concers is to do a trans quick learn this must be done at the dealer with DRB

 

thanks.. ill take that to them tomorrow and schedule it for monday.. maybe they will listen... this is annoying to run this thing in and out of the dealer..