oil pressure

just had my oil changed, and now my oil pressure gauge fluacatutes, it goes from 40 t0 0ver 60 then back to 40.this is at 55mph. at slower speeds in town seems to stay around 40 maybee a little lower. any thoughts??

Put on a manual guage and test. Maybe your sender went bad.

u could have a bad cluster too. known to go out on these chevy's.

thanks, i don't have the gauge to check it so i am going to have it looked at by a shop on tuesday. i took it by him to see what he thought and he said sane theing it is best to put on the mannual gauge just to be sure,but he thought it probally the sending unit thanks for the help