How to change Alternator '99-'06 Silverado/Sierra

[Chevyman]

I just upgraded my factory 105amp alternator to a 130amp. If you are doing this mod you need to buy a longer belt. I recommend the Goodyear Gatorback 4060930. This is for a 99-06 Silverado/Sierra v8 5.3. Here is a couple pictures of how I installed it and the basic tools you need to get the job done. This should take you about 30 minutes to install

Tools required: Sockets- 8mm, 10mm, and 15mm.

1. Disconnect the negative battery terminal using a 8mm socket, If you have the theftlock audio system be sure the lockout feature is turned off.

2. Remove the dirvebelt using a 15mm socket, make a note of the belt routing. and rotate the tensioner to release the belt tension.

3. Disconnect the output wire using a 10mm socket and remove electrical connector from the alternator.

4. Remove the 2 mounting bolts using a 15mm socket.

5. Remove alternator from engine.

6. Reinstall new alternator and 2 mounting bolts using a 15mm socket. Torque the 2 mounting bolts to 37 Ft-lbs.

7. Connect the output wire using a 10mm socket and reinstall electrical connector.

8. Install drive belt.

5.3 belt routing

9. Reconnect negative battery terminal, and check the charging voltage to verify proper operation of the new alternator. Connect a voltmeter to the negative battery terminal and to the positive battery terminal. With the truck off you should get approximately 12.4-12.6 volts. Next crank your truck and with the voltmeter still connected to the negative terminal and postive terminal you should get greater than previous volts recorded but no more than 14.7 volts.

 

[ScottyBoy]

Nice write up.

That's a nice Gatorback you have there too. I installed one on my truck over a year ago and it still looks brand new.


And one other addition, when upgrading from a 105amp to a 130 amp, you must buy a new belt because the 130amp uses a slightly longer belt.

 

[buRRp]

Very nice write up.

 

[Chevyman]

Nice write up.

That's a nice Gatorback you have there too. I installed one on my truck over a year ago and it still looks brand new.


And one other addition, when upgrading from a 105amp to a 130 amp, you must buy a new belt because the 130amp uses a slightly longer belt.

Yeah I use Gatorbacks on all my vehicles. Thanks for reminding me about the belt I forgot to add that, but its in there now.

 

[daddy]

Thanks for that write-up!

Just for conversation, what was the purpose for the upgrade? Did your old one die so you just stepped up or did you have a power need for it?

 

[Chevyman]

My old alternator was still working, but I am in the process of putting electric fans in.

 

[daddy]

Gotcha!

 

[Black02Silverado]

Nice write up.

That's a nice Gatorback you have there too. I installed one on my truck over a year ago and it still looks brand new.


And one other addition, when upgrading from a 105amp to a 130 amp, you must buy a new belt because the 130amp uses a slightly longer belt.

Yeah I use Gatorbacks on all my vehicles. Thanks for reminding me about the belt I forgot to add that, but its in there now.

Just wondering, why the longer belt? Is the alternator that much different in size or is it the pulley bigger? I would think that the inside of the alternator is what makes the difference not the physical size of the case and pulley.

 

[Z71 Kris]

its either or, I dont remember which is bigger, I know when I upgraded my alt to a 145, I got the longer one as well....

 

[bubbatrucklover]

Nice right up and the routing pic is INVALUABLE. You would think one could remember it but NOOOOOO.

Just an FYI for those interested. When upgrading my charging system I went with a 200 AMP (100 Amp idle) from these guys:
http://www.motorcityreman.com/99sigmcsi445.html

100% new parts no reman with core charge. At the time it was the same price as a 145 Amp I was looking at and uses the stock belt.

I completed the system with an Optima yellow top and the Big Three Upgrade.