I have an 02 chevy 1500 5.3 V8 Check engine light comes on and then it shifts hard from 1st to second. Shifts smooth in all other gears. Cleared the code P7081 i think. Transmission slipping detected. Drove 20 miles to town on the way back out from 45 mph going to 65 as the torque converter kicked in the light came on instantly again. Won't do this unless it's warm either shifts fine when it's not up to temperature. I've read some forums that say replace the valve body and others that say you only need to replace the 1-2 accumulator within the valve body 160xxx miles gears in the transmission were replaced at 130xxx. Any help would be greatly appreciated.