My 2001 ranger 4x4 4.0 SOHC recently decide to start slipping reverse and in the past day or so won't back up at all. A few months back I devolped a leak on one of the lines and repaired it. When I checked the fluid level there was way to much fluid in it. My question is tomorrow I am planning on changing the filter and fluid and was wondering if there could have been any damage due to overfilling the fluid level and what should I look for?

 

No Reverse only:

Fluid
--incorrect level
-adjust to correct level

Shift linkages (internal/external)--Transmission shift cable and bracket-damaged or misadjusted. Digital TR Sensor out of adjustment
Fix by Inspect for Damage, readjust as required. Repaair all damaged components. After repairing linkages, readjust the digital TR sensor.

Incorrect Pressures:
Incorrect Band/Clutch application pressures Line pressure low
Fix by Check line pressure at tap. Carry out line pressure and stall speed tests Rever to the line pressure chart for specificationns. If pressure is low, chcek the reverse clutch component

Filter and Seal Assembly:
Filter damaged or plugged. Seal damaged or cut or missing.
Fix by Inspect for damage and install a new filter. Ford only please.

Main Control Assembly:
Screw out of torque specification
fix by tighten to specification
Gasket damaged or off location
fix by inspect and install new gasket
Separator Plate damaged
Fix by inspect for damage repair as required.
1-2 Shift Valve, or 2-3 Shift Valve, or Reverse Modulator Valve, or Spring damaged or missing or misassembled stuck bore damage
Fix by inspecting for damage, repair damage
Pump damaged or leaking
fix by inspecting and repair as needed
Direct/Reverse Clutch Reverse Band
Carry out air pressure test, inspect for damage repair as required or Check and install a new piston seal. Check and install a new low/reverse band.

That's the 2001 Ranger service manual for 4R44E.