I thought my tranny was going out so i bought my buddies freshly rebuilt hd tranny triple disc convertor vb billet input and full suncoast rebuild and after installing it i found out when my truck is cold it still kicks out of overdrive but it only happens when its cold outside so i thats the only thing that makes me think it could be something else any ideas or does it sound like its the tps forsure?

ps my tranny can b warm (+/-140*) but if the trucks cold it kicks outa overdrive.. if i stay between 50-55 itl hold overdrive i can steaily accelerate past 60 and randomly rpms jump to 2400 rpm

thanks

 

unless somebody screwed up the tranny build it could possible be the tps but i would start by making sure its not throwing any tranny codes when my stock training started kicking in and out of overdrive it was the sending unit for the tranny and of course the bands not being adjusted but since you have a fresh rebuild you can test the tps genos garage website has a link to a ton of info on fixing common problems with this generation truck
Ram Diesel Problems

 

sending unit as in PCM?