1994 mazda b2300 it grinds when i down shift to second and first gear unless i drive very slow(like 5 to 10 mpr)

SOURCE: transmission shifts hard down from highway gear only (D>3rd)

I had the same thing! It was a computer issue. It only cost me about $35.00.

SOURCE: 1994 nissan sentra shifting hard

change fluid in trans add lucas for trannys let me know if theres metal in the pan or if you have trouble tell fixya bout me ok

SOURCE: Engine stalls when shifting into any drive gear.

It sounds like your idle air control valve could be going out on you.  The extra stress from being in gear can cause the car to stall out if the IAC valve isn't opperating properly.  The IAC is attached to the throttle body and is normally held on by two screws.  IAC valves are relatively cheap from AutoZone and easy to replace.  That would be my best guess based on your description.  Good luck and let me know if you have any other questions.  Thanks for an honest rating and for using FixYa!

SOURCE: Transmission hesitates shifting into second and perhaps third gear when driving slow. When acceleration is positive transmission shifts smoothly. Reference "99 Mercury Transmission" as Subject when

Several things could be causing your problem:

1. Auto transmission fluid is low
2. Auto transmission fluid needs changing; this is an area that gets neglected by a lot of people;check the fluid and if its brown or gives off a burning smell, it needs changing. Very old transmission fluid will cause slipping in the transmission; if this is the case, it should be changed along with the filter

SOURCE: Mazda 626 - Hard to shift into gear.

With any vehicle that has a hydraulic clutch, a worn master cylinder or slave cylinder will give this very symptom. First step is to check the fluid in the resivor. If it is low, you will want to check for fluid bypassing the seals. Be sure to check under the rubber dust cover as fluid can collect there and not be readily visible. Also, if the fluid in the resivor is dark colored, it is an indication of the internal seals going bad and you will need to replace the cylinders.