try changing fluid and filter (if any)
Sure, but you will have to change many, many, many other parts along with the transmission. I would suggest purchasing a 1990 Bronco like yours that has a standard transmission to use as a parts car.
Yes
That's going to depend on what transmission you have. In most cases, they shift in a similar fashion to any other Class 8 truck with an unsynchronised transmission. But some have other transmission types.
the axle is a shaft that goes into your rear end from one side with the wheel bolts on it and the other connecting into you rear end differential gears.
bad linkage in shifting cable
the only solution that you can affect at home is to check fluid level, and change the fluid and filter this should be done about every 30,000 miles, all other issues need to be dealt with by a reputable transmission specialist.
As I understand it: Manual: There are a set # of gears (usually 4-6) and you switch between them as required. Automatic: Again a set # of gears (usually 3-5), the transmission switches them automatically, based on current speed and other variables CVT: Instead of having a set # of gears, there is a belt (or chain?) between the only 2 "gears" that exist. Difference being that 1 of those "gears" changes it's circumfrence, giving it an unlimited # of gear ratios. The transmission determines what the appropriate gear ratio should be, based on speed, how hard you press the pedal, load, etc. Hope this helps.
The modulator valve on a 1994 Ford Bronco is located on the transmission, specifically on the right side of the transmission case. It is typically mounted on the valve body of the automatic transmission, which regulates fluid pressure based on the engine load and throttle position. To access it, you may need to remove the transmission pan, depending on the specific setup and whether any other components are in the way.
If your car isn't shifting into any other gears, I would suspect the Transmission control unit
with mine the transmission was going out and it could be something as little as a bolt or as big as the transmission itself (my ford has 227000)
If it's like other Fords, the synchros break down, preventing the transmission from changing gears. Getting a manual transmission should avoid this problem.
Usually either Park (P) or Neutral (N). Pretty much any car will only crank in those gears, and even if the car could crank in other gears it would probably damage or destroy the transmission