Is this a hard shift or is it going back & forth between the gears ?
What is the make,model,year & engine size of your vehicle ?
2003,gmc sierra 1500 5,3liters engine z71 model...hard shift between first and second.
the truck kick when the first speed stay engage up to 3000rpm and when she shift to the
second it kick in my back...nothing between 2 and 3 and 3 and 4.
Usually this condition is caused by a sticking valve in the valve body of the transmission.Here are some more things that can cause it.
Valve Body Assembly (60)
2-4 Servo Assembly (13-28)
2nd Accumulator (55-57, 104)
2-4 Band (602)
Worn or mispositioned
Oil Pump Assembly (4) or Case (103)
Faces not flat