How to Replace a 1995 GMC Truck Alternator

General Motors purchased the Rapid Motor Vehicle Company, which specialized in commercial trucks in 1909. Once the sale was complete, GMC was born. After 86 years in business, GMC was the second best-selling line of trucks from the major American automakers behind the Ford F-Series with their 1995 lineup. Regardless of the model or engine, all the GMC trucks derive electrical power from an alternator, mounted at the top-front of the engine. Since the alternator provides all the engine's electrical needs -- if the alternator fails -- replace it immediately.

Instructions

1

Park the GMC on flat ground and set the parking brake.

2

Open the GMC's hood. Rotate the serpentine belt tensioner counterclockwise to relieve tension on the belt. Slip the belt off the alternator pulley with your other hand and then slowly move the tensioner back into place.

3

Remove the negative battery cable from the battery with a battery wrench. Move the cable end to a place where it cannot contact any metal components during the repair.

4

Remove the alternator ground-wire nut from the back of the alternator using a socket wrench and 13-mm socket. Pull the wire off the alternator and move it aside. Unplug the engine wiring connector from the alternator.

5

Unbolt the alternator from the alternator bracket with the socket wrench and 13-mm socket. Lift the alternator out of the alternator bracket and set it aside.

6

Compare the old alternator and the new alternator to one another. Make sure they are physically identical by checking pulley size, mounting bolt hole locations, wiring connector locations and the rear-mounted voltage regulator size and shape. If they are not physical twins, take both to your retailer and match the old alternator up to a proper replacement.

7

Set the new alternator into the alternator bracket, with the pulley facing forward. Bolt the alternator to the bracket with the socket and wrench. Plug the wiring connector into the new alternator and then bolt the ground wire to the back.

8

Reinstall the serpentine belt on the alternator pulley in reverse of how you removed it. Reconnect the battery cable in reverse of how you disconnected it. Close the hood.