tranny problem

my 1990 daytona (same shit as labaron) will not shift into 3rd gear it always stays in 2nd.....what is wrong with it. it is a 4 speed overdrive tranny with a 3L v6. and how come my tach works sometimes and sometimes it does not work. i here a strange noise coming from the back of my car kinda like a grinding noise.

i'm not absolutely sure with the tach, it could be many things. The grinding noise could be wheel bearings, or the brake shoes dragging or something else. I know why the transmission is not shifting into 3rd. You probably have dropped the pan sometime and changed the filter. This is 90% of the time caused by the transmission sucking a little bit of air into it. this could be caused by a bad o-ring, or just not full. The only way to fix this is for one, get the air out of the system and two, take it somewhere where they have a DRB II code scanner for the transmission control module(TCM) and clear it. After this is done you should be fine. Just remember not to add anything except ATF+3, +4, or +5 (I personally use atf+3 with a bottle of lubegard atf protectant)

yeah i got the tach fixed.... that grinding noise is still making noise when the car is not moving and is in park. yeah with the tranny i will have to try it.