I have a '98 1/2 2500 24 valve. A few weeks ago it started cycling in and out of overdrive at about 40 mph. I did the APPS reset procedure and the shifting was fine for a while. Yesterday the same thing happened again, but part of the time it would lock in 2nd gear when starting out from a stop. Sometimes I could shift to neutral and restart the engine and it will shift right. I 'm doing the APPS thing again now, but I don't think it will help for long, if it will help at all. I would appreciate any advise you guys can give!!!!!!

 

try the key trick and check for codes

 

Thanks, but the key trick for codes dosen't work until after 2000 models, although p0753 is the only code showing...