I have an 06 chevy aveo LS manual transmission was low on fluid and over heated would not shift after over heating sat for a year drained fluid and put new in when we got it back together. Now when you go to shift into 1st or reverse it goes into 3rd gear and second is 4th gear what could be causing this to happen. shifter acts like it is in gear in 1st and 2nd but can grab the linkage and acts like it is in neutral. Cant do that with reverse acts likes its in gear but its In 3rd gear