My mazda is not change gears what is the problem

Did you use the correct oil grade when changing the trans fluid

Sounds like it need gear oil changed or gears are not meshing right do to wear or bearings

Get the transmission serviced, either a worn gear, bearing, or bad synchronizer.

Try Mazda spares and check as the gears ratio's will be different for each model but the gear itself may still fit in your car. There are ratio change gear boxes from speed shops . These fit onto your gear box and the cable / sender unit fits onto it . The ratios are changed inside the little adaptor.

You basically need the trans rebuilt. The only way the speed sensor could affect any of the shifting problems is if it broke off into the trans. somehow. You could try checking the trans fluid first, or having it changed.

It sounds like clogged ports that allow fluid to go through. Reverse will most always work even when the entire tranny goes since it is it's own separate system. Try a flush, I don't normally advise that but it sounds like the way to go but I'm guessing a new tranny is in the very near future. Did you keep up on the fluid changes? Because those trannys in those mazdas usually go for a good 300k if kept up with maintenance.

1.remove speedometer driven gear
2. remove drain plug, and drain oil
3. fill trans, check fluid by speedometer gear, just above gear see F & L, oil level is between F & L
4. install speedometer driven gear

the transmission and filter need to be changed quickly, the oil is most likely burnt and/or the filter is covered with funk, once those are swapped then your ride should cruise just fine.

sounds like a shift solenoid in the trans.

hi

it seems that the gear bushings have worn out. you need to take your car to a mechanic to have the bushings changed. Also, please check it your car has enough Automatic Transmission Fluid.

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RAhUL_hunk