How to Replace Alternator 03-04 GMC Envoy XL

Difficulty: Intermediate · About 35 min · Gmc Envoy

Replace the alternator on a 2003-2004 GMC Envoy XL.

Steps

1. Disconnect the battery

   Disconnect the negative battery cable with an 8mm wrench.

2. Remove the air intake hose

   Loosen its two clamps with a screwdriver, remove the T30 bolt holding it, then pull it off.

3. Release the serpentine belt

   Note the routing, fit a 15mm socket to the tensioner, push it down to slacken the belt, pull it off the center pulley, release the tensioner, then slip it off the alternator.

4. Remove the old alternator

   Unplug its wiring harness, pull back the lead boot, remove the 19mm nut and the lead, remove the two 15mm bolts, then pry the alternator out with a screwdriver.

5. Install the new alternator

   Hammer out the alternator's bolt rings if stuck, lower it into place, insert the two 15mm bolts, reconnect the wiring harness, seat the lead on its stud, fasten the 10mm nut, then refit the lead boot.

6. Reinstall the serpentine belt

   Pull it over the alternator pulley, confirm the routing, then use the 15mm socket on the tensioner to walk it onto the center pulley before releasing.

7. Reinstall the air intake hose

   Fit it back on, tighten its two clamps, then tighten the T30 bolt.

8. Reconnect the battery

   Reconnect the negative battery cable.

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