How to Replace Alternator 98-12 Ford Ranger 4.0L V6

Difficulty: Intermediate · About 60 min · Ford Ranger

Replace the alternator on a 1998-2012 Ford Ranger with the 4.0L V6.

Steps

1. Disconnect the battery

   Note the serpentine belt's routing first, then disconnect the negative terminal with a 10mm wrench.

2. Move the intake tube and engine cover aside

   Remove the throttle body cover's Phillips screws and single 7mm bolt, take off the engine cover, then loosen the intake tube's two hose clamps and pry it off.

3. Release the serpentine belt

   Fit a 3/8 inch drive ratchet into the tensioner, turn it clockwise to slacken the belt, then slip the belt off the alternator and release the tensioner.

4. Remove the old alternator

   Pop the alternator connector loose with a hooked pick, disconnect the exciter wire on the back, remove the ground's 10mm bolt and the three 13mm mounting bolts, free the wiring harness clip, then lift the alternator out.

5. Transfer the extension piece to the new alternator

   Remove the 10mm nut and tab from the new alternator's back, pull the red cap and 11mm nut off the old extension piece, slide the extension onto the new unit, then tighten the nut and press the cap back on.

6. Install the new alternator

   Set it in place, hook the wiring harness tab onto the top bolt, tighten the three 13mm bolts to about 35 ft-lb, then reconnect the exciter wire, wiring harness and ground.

7. Reinstall the serpentine belt

   Confirm the routing, then use the 3/8 inch ratchet on the tensioner to pull the belt over the alternator before releasing it.

8. Reinstall the intake tube and covers

   Fit the intake tube to the throttle body and air box and tighten its clamps, then refit the engine cover and throttle body cover with their screws and bolt.

9. Reconnect the battery

   Reconnect the negative terminal.

Check your vehicle’s repair manual for exact specifications and fit.