hi there

i was wondering if anybody here got step by steo ignition lock cylinder replacement on 99 4.3 l express cargo van.
earlier today i went to start it. the key wouldnt move the full range of motion that i am used to.and nothing happens. then i forced it just a hair and the van started. so i am assuming its the tumbler. unless someone here has other opinion. i would really appreciate the help.
thanks in advance

 

Try these. Have you tried wiggling the transmission column when you meet the resistance?

chevy ignition - YouTube

 

thanks pitcrew.i looked ito trans. col. its not the culprit. i appreciate your input.