How to Replace the Alternator in a Toyota Highlander

The Toyota Highlander has an alternator that sends electrical current to various devices in the vehicle while the engine is running. Most alternators made today include a voltage regulator that ensures the voltage level remains constant. You may need to replace the alternator if your battery keeps running down or your headlights become dimmer while driving.

Instructions

1

Determine which alternator your Toyota Highlander will need. You'll want to be sure the new alternator is compatible with your Highlander's engine. Models made before 2008 may have a 2.4 L, 3.0 L or 3.3L engine. The current version has a 3.5 L 2GR-FE engine.

2

Disconnect the negative battery cable with a socket wrench. Remove the electrical connector and the retaining nut on the alternator terminal with a socket wrench. This will allow you to remove the battery terminal wire on the alternator.

3

Unfasten the pivot bolt and plate washer, and adjust the lock bolt from the alternator with a socket wrench. Remove the drive belt and take the alternator off the vehicle.

4

Install the new alternator assembly. Replace the drive belt and adjust the tension to 170 to 180 lbs. for a new belt and 95 to 135 lbs. for a used belt. Use a torque wrench to tighten the adjusting lock bolt to 13 foot pounds. Install the plate washer and torque the pivot bolt the 41 foot pounds for a 3.0 L engine and 43 foot pounds for a 3.3 L engine.

5

Connect the electrical harness and battery terminal wire to the alternator and fasten the retaining nut to the alternator terminal with a socket wrench. Reconnect the negative battery cable with a socket wrench.