Alternator Replacement

[Grady_Wilson]

Finally found a video. It’s a stretch belt and it seems like you need a special GM tool, or what this guy does, zip tie and turn the motor.
With that said, I’m not going to cut the belt and replace the alternator. I’ll just pay the dealer. I don’t need it completely out of commission in case it’s something more severe than just an alternator.

I was just about to post that exact video after looking at the first page of this thread.
Stretch belts lower costs because there is no tensioner needed.
Personally, I prefer the old school, loosen the alternator bolt, use a pry bar to tighten the belt and tighten the alternator bolt.
This new stretch belt stuff is nonsense.

 

[Joseph Garcia]

My main question is how do I loosen the belt tensioner? It feels like the hub is going to come off, not spring loaded.
I have replaced the battery, 6 months ago and am getting service charging system fail.
Trying to replace the alternator first before going to the dealer. 2.5yrs and 42,000 miles in.

Don't you have a local repair shop that could replace the belt for you and troubleshoot, if necessary? It would be far cheaper than the local dealer and will achieve the same result.

 

[fozzi58]

Make sure the battery is tested properly.

If the alternator is bad, I would consider looking at a Mechman. Even their base models which is a factory replacement is worth a few dollars more for a more reliable unit.

If you don't have an auto mechanic that is good at electrical diagnosis, consider looking for a shop that does custom auto sound. They may already be familiar with aftermarket alternators and increasing the power output to support the electronics in the truck.

A lot of us do the "Big 3" wiring upgrade. The GMT900 and K2XX platforms are known to have battery ground cables that rot from the inside out. Replacing that cable with a high quality cable may help your charging issues as well.

 

[Oaktree]

I decided to try the replacement. The ground is toasted/melted into the alternator so it’s a good place to start.
I’m not sure if GM does this on purpose or not. Can’t get the second alternator bolt out without having to remove the fan shrouding.

 

[OR VietVet]

Just leave it in the hole and when lift out the alternator, it will fall out. Just remember to reverse this process when reassemble.

 

[Oaktree]

You can’t really leave the bolt in, the front bracket is 1/4” wide. picture of that bolt below.

So what I had to do, remove the upper radiator hose, two bolts holding the fan housing, remove all the piping clips which are connected to the fan housing, disconnect the fans, lift the housing up to extract the bolt and place a new one in.
This is not you old simple alternator removal.

Now looking at the voltage readings on the dash, this has been trouble for a while (I have another post on it), probably since I had the motor replaced. I tried to remove the ground and as you can see, it snapped off. Ground issue…?

Now the readings on the dash are hard center with a charged battery which looks more normal to my eyes.

In all, $200 alternator, $40 new belt, $6 24mm socket, $20 belt tool. And about 4 hours of my labor figuring it out.

 

[Doubeleive]

You can’t really leave the bolt in, the front bracket is 1/4” wide. picture of that bolt below.

So what I had to do, remove the upper radiator hose, two bolts holding the fan housing, remove all the piping clips which are connected to the fan housing, disconnect the fans, lift the housing up to extract the bolt and place a new one in.
This is not you old simple alternator removal.

Now looking at the voltage readings on the dash, this has been trouble for a while (I have another post on it), probably since I had the motor replaced. I tried to remove the ground and as you can see, it snapped off. Ground issue…?

Now the readings on the dash are hard center with a charged battery which looks more normal to my eyes.

In all, $200 alternator, $40 new belt, $6 24mm socket, $20 belt tool. And about 4 hours of my labor figuring it out.
View attachment 439655

that's the + (positive) post, the ground is made when it is bolted to the engine/mounting bracket. the 2-pin small connector (also broken in photo) sends the on/off signal (digital) from the computer/ecm