Hard shifting transmission......after an alternator change????

[itsdish]

Just replaced my alternator, and I have 195,000 mile on my 1996 Tahoe. Now its seems as though my transmission shifts very hard, especially from 1st into 2nd gear. Please offer suggestions. Thanks

[Jim Adams]

It sounds like you may have knocked a vacuum line off or somthing like that. Easiest way to be sure is to ,,first look real good lol then jack up the truck or if it is high enough climb under it and pull the vacuum line off the modulator and see if it has suction while it is running,,,if it doesnt then you knocked it off and you need to look real good,if it does have suction then try this,( chances are you have a 700 trans and dont have a modulator valve ) BUT,,disconnect the battery then push brake pedal down 3 times ,,wait a few minutes then reconnect battery cable and then try it agin and see if that fixes it. sometimes the puter gets confussed and the text book says to not only disconnect battery cable to reset but also to push on brake pedal a few times as it will then fully clear codes. good luck

[itsdish]

Thanks for your help....once the codes were cleared, the transmission started to run smooth once again. The computer must have been sending bad info after the alternator change.....Thanks again


Dish