How to fix Ford Ranger stick shift that has a transmission leak

Ford Rangers with a manual transmission can leak from a number of places. When determining a leak, the first thing that you have to do is determine what is leaking. If there is a spot or puddle of fluid under the truck, examine what is in the puddle. If there is not a puddle, there might be drips hanging from the transmission, a bolt or a line. It could be water, motor oil, brake fluid, transmission fluid or gear oil if you have a 4x4. The water will just look like dirty water. If it is motor oil it will feel thick and sticky and is usually black. The brake fluid is almost clear and has a thin consistency. The transmission fluid, when new, is red. It will have a red tint to it. It is not as thick and motor oil, but not as thin as the brake fluid. The gear oil is brown when new. Its consistency is between the transmission fluid and the motor oil. It will feel thicker than the transmission fluid but not as sticky as the motor oil.
Once it is determined what is leaking, next determine where the leak is coming from.  Look for the highest wet place on the transmission.

The Manual 5 speed can be leaking either brake fluid or transmission fluid. If it is brake fluid a drip will probably be hanging on the lowest point on the bell housing, where the engine and transmission bolt together. Brake fluid could also be hanging from the hose that runs into the side of the transmission on the driver’s side towards the front of the transmission. If this is the case, then the slave cylinder is bad and the whole transmission will have to come out and the slave cylinder will have to be replaced. If the clutch has a lot of miles on it, this would be a good time to replace the clutch also.

If transmission fluid is what is leaking, then determine where it is coming from. Again look for the highest point on the transmission that is leaking. A few places that could leak are: the output shaft seal, the speed odometer, or the front input shaft seal. Any of these can leak, but one that is hard to catch is the shift rail plugs. These are 3 little plugs that go in the back of the top of the transmission. These little black rubber plugs will not leak much at a time, but leak just enough to keep the back of the transmission wet. A lot of times it will look like the speed odometer or rear output shaft is leaking.
It is not hard to replace these plugs. Most people who change their own oil would be able to replace these themselves.

Tools Needed:
A jack
Jack stands
Metric socket set
Metric wrench set
Small pry bar or flat screw driver

Parts Needed:
Replacement plugs (inexpensive from Ford dealer)
New plugs will be metal knock in plugs resembling a freeze plug
Transmission fluid


  1. Jack the front of the truck up, securing it with approved jack stands.
  2. Remove the drive shaft
  3. Remove the cross member to allow the back end of the transmission to swing down
  4. Use the small pry bar or screw driver to pry out the 3 black plugs on the top of the transmission. A pair of pliers may also work to pull the plugs out.
  5. Clean the 3 holes where the new plugs will go.
  6. Use a small socket and hammer to drive in the new plugs
  7. Replace the cross member
  8. Replace the drive shaft
  9. Fill the transmission with fluid.
  10. Wipe off and excess fluid and dry the back end of the transmission
  11. Lower the truck.
  12. Drive the truck a few miles.
  13. Recheck fluid and check for leaks