I work on the air belt and I have always been on the air belt never did anything else before that. We got a new employee the other day and my sup want to train him what I do so he want me to go load trailers on fridays, so the new guy can learn my job. I think going to load the trailers is a downgrade in my job. Can the union help with this or do i just have to load the trailers.
Assuming you are part-time, if you have six months seniority or more, you should have been allowed to bid the Type of job you want, (but not the specific job.) You would then move to that job category when an opening occurs, (unless someone with more seniority is ahead of you.) If you do have six months or more seniority, but never actually bid your air belt job, then I'd argue that you have, in effect, bid it by default. See Article 22, Section 4.
http://www.browncafe.com/community/threads/ups-teamsters-national-master-agreement.335360/
In general, The Rule, as the Union will tell you, is: Work As Directed Now, Grieve Later. Never refuse an order, unless it is unsafe or illegal.