02 Converter lock up
 

Ok guys, my dad called me the other day wanting to know if i knew of a commom problem with the allison not wanting to lock the converter unless the truck has been running for awhile and is up to full operating temp. The truck has never done this and just up and started one day and kept getting a little worse. When the converter does lock it locks up solid and no problems nothing unusual, but until its been driven for 5-10 miles sometimes for the most part it wont lock up. Anyone have any ideas?

My Trans temp has to be at least 100º before my converter will lock. Its always been this way. In the winter it may take 10 miles for it too warm up enough.

Makes since but this truck hasn ever done this before, however that doesn mean it cant go and change its mind lol, so thanks for the help!