Chevrolet Repair: trans trouble, 2 quarts, trans shop

Question
HI MARK,I HAVE A 97 2WD SONOMA 4.3L AUTOMATIC WITH 110,000 MILES.WHEN I DRIVE OVER 20 OR 30 MILES IT SHIFTS HARD FROM 1ST TO 2ND,SO HARD IT CHIRPS THE TIRES,BUT IT SHIFTS FINE THROUGH THE OTHER GEARS.IF I SHUT THE TRUCK OFF FOR A MINUTE ITS FINE WHEN I START IT BACK UP,UNTIL I DRIVE FOR A WHILE AND COME TO A STOP,IT TAKES OFF FINE BUT REALLY SLAMS INTO SECOND GEAR.I HAVE ONLY HAD THIS TRUCK A COUPLE MONTHS SO I DONT KNOW A WHOLE LOT ABOUT IT.I DO KNOW IT HAD ABOUT 2 QUARTS TOO MUCH TRANS FLUID IN IT WHEN I BOUGHT IT,WHICH I SUCKED OUT.THE TRANS FLUID LOOKS PRETTY DARK.WOULD I BE LUCKY ENOUGH TO FIX THIS PROBLEM WITH A TRANS FLUSH AND FILTER?YOUR ADVICE IS MUCH APPRECIATED.THANKS

Answer
Hi Nathan, I think you might have a problem in the valve body. This could be a valve that is sticking or a solenoid that is bad. I would take it to a trans shop or a dealer to get it scanned to check for any codes in  the trans. This would be the first place to start. The trans will shift hard to save itself from burning up when a problem is detected by the computer.

    When the fluid gets dark it is not a good sign. The clutches could be slipping or the fluid has been overheated.

Hope this helps, sorry I don't have more info for you

Have a Nice Day               Mark