Can a floor truss be adjusted/moved (in basement) to center a shower drain (on 1st floor)?

It could be done, but would be a big mess. If you move it very far, you would need to put in something to support the floor. If the floor is already finished above, removing it would be tough. You might do better to box a short section off with headers and put in 2 short joists about 11'' apart. . You want good support under a shower so that the pan doesn't sag and open the drain pipe.

Can a floor truss

By the way, just for future reference, it's called a "joist". Trusses are those angled beams in your attic that hold the roof up.

HTH,
Moishe

Depending how they are manufacutured there is such thing as a flooor truss. There are floor joist wich are solid 2x's, there are I-joists which are usually plywood w/ a 2x top and bottom cap, then there are floor trusses w/ 2x' is a truss (web) like formation.

Aha. Thanks for clearing that up.