How do I identify what alternator I have in a '04 Yukon Denali

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talkyukon

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I have a 2004 Yukon Denali 6.0 and it has an Delphi alternator I believe stock OEM and I can't tell if it's 105 or 135 amp alternator.

How do I identify what size I have so I can get the right alternator I ordered a 105 amp alternator from Amazon it's the AC Delco Gold but I'm not sure if it's going to fit. The alternator is having bearing noises but it works so I was going to replace it because of all the noise the bearing makes.

I want to make sure it fits the the belt size that's already in there cuz the belt is still good
 
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Doubeleive

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I have a 2004 Yukon Denali 6.0 and it has an AC Delco alternator I believe stock OEM and I can't tell if it's 105 or 135 amp alternator.

How do I identify what size I have so I can get the right alternator I ordered a 105 amp alternator from Amazon it's the AC Delco Gold but I'm not sure if it's going to fit. The alternator is having bearing noises but it works so I was going to replace it because of all the noise the bearing makes
unless you are running some aftermarket lights/amp, etc then it doesn't "really" matter. 105a is the lowest one you can effectively use. 145a or 160a would be better.
you can always go up without any issue, wiring, fuses, relays are all the same regardless. the most important part isgetting one with the correct harness connector it will either be a
2 pin or a 4 pin. 2004 is a year that could have either one
 

justirv

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unless you are running some aftermarket lights/amp, etc then it doesn't "really" matter. 105a is the lowest one you can effectively use. 145a or 160a would be better.
you can always go up without any issue, wiring, fuses, relays are all the same regardless. the most important part isgetting one with the correct harness connector it will either be a
2 pin or a 4 pin. 2004 is a year that could have either one
I agree that you can go up in alternator amperage with no issue, to a point. 145A-160A is a good stock upgrade and will drop in. If you go "big" (200A +) due to dual batts, big stereo, etc., its always a good idea to increase your conductors (cable), and fusible link size. It's also a good time to do the Big 3 (or 4) grounding upgrade. Also, I'm always cautious with "GM" purchases from AMZ. I prefer other vendors such as Rockauto for authenticity.
 
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talkyukon

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I have a 2004 Yukon Denali 6.0 and it has an Delphi alternator I believe stock OEM and I can't tell if it's 105 or 135 amp alternator.

How do I identify what size I have so I can get the right alternator I ordered a 105 amp alternator from Amazon it's the AC Delco Gold but I'm not sure if it's going to fit. The alternator is having bearing noises but it works so I was going to replace it because of all the noise the bearing makes.

I want to make sure it fits the the belt size that's already in there cuz the belt is still good
I figured it out.
There is a serial number and a stamp that says 145amp on it on the alternator
So its a bosche delphi 145 amp alternator
 

Doubeleive

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I agree that you can go up in alternator amperage with no issue, to a point. 145A-160A is a good stock upgrade and will drop in. If you go "big" (200A +) due to dual batts, big stereo, etc., its always a good idea to increase your conductors (cable), and fusible link size. It's also a good time to do the Big 3 (or 4) grounding upgrade. Also, I'm always cautious with "GM" purchases from AMZ. I prefer other vendors such as Rockauto for authenticity.
*do not ever increase the fusible link
why? because the fusible link is built to prevent everything behind it from burning up, increase the link and you risk destroying modules, wiring, as well as a risk of fire.
upgrading the charge cable is standard

i should add that simply increasing the alternator amperage does not increase how many amps the vehicle will use, the extra amps just makes it a lighter load on the alternator.
any external/aftermarket equipment requiring more power should be wired separately with it's own wire and fuse's, relays, etc i.e. amps, high power lighting, cb, ham, etc
 
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justirv

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*do not ever increase the fusible link
why? because the fusible link is built to prevent everything behind it from burning up, increase the link and you risk destroying modules, wiring, as well as a risk of fire.
upgrading the charge cable is standard

i should add that simply increasing the alternator amperage does not increase how many amps the vehicle will use, the extra amps just makes it a lighter load on the alternator.
any external/aftermarket equipment requiring more power should be wired separately with it's own wire and fuse's, relays, etc i.e. amps, high power lighting, cb, ham, etc
If one was to upgrade to a 225A, 325A, or any other (extremely) high output alternator, how are you gaining any additional amperage output or draw by utilizing the oem cable? Upgrading the cable plus upsizing the fusible link for that specific cable is paramount to full utilization. Throwing various components in the mix without performing the necessary electrical calculations can be detrimental. In no way was I implying to upsize the fusible link capacity on existing, oem cabling or components.
 

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If one was to upgrade to a 225A, 325A, or any other (extremely) high output alternator, how are you gaining any additional amperage output or draw by utilizing the oem cable? Upgrading the cable plus upsizing the fusible link for that specific cable is paramount to full utilization. Throwing various components in the mix without performing the necessary electrical calculations can be detrimental. In no way was I implying to upsize the fusible link capacity on existing, oem cabling or components.
because there shouldn't be anything sizeable attached to the other side, the only part you have to be concerned about is the charge cable from alternator output to battery positive post. everything else stock will work just as it was intended too and just like it did with a lower amperage alternator.. the draw on the alternator will not increase, the alternator will simply have less strain on it. Unless you add other 3rd party equipment.
the alternator will not get as hot because it is capable of providing the same or more output as the lower amperage alternator with less work.
the effect is opposite if your vehicle came with a 160a and you throw a 105a on it that alternator is going to get worked hard and it's going to get really hot, battery may not get charged up properly, lights may flicker, or any other variety of low power issue's.

the kicker is all the oem fuses and relay ratings, wiring gauge, etc is all the same regardless if your vehicle came with a 105, 145, 160 or more amperage alternator.

adding heavier gauge wiring and grounds is of course a good idea (pre-fusible link) but is not a requirement.

and again 3rd party upgrades should not be attached to the factory wiring unless they are low draw and do not exceed the fuse rating for that particular system
if you are adding a ham radio, radio amps, ac converter, light bars, yada yada those should all be directly attached to the battery positive post with there own dedicated wiring, matched fuse rating (per device) and grounded to the frame at the closest possible location. because any fault will follow the shortest path

adding a 400w light bar to the factory lighting harness is just asking for it.......... same for anything else requiring more power, the factory harness was not designed for that.
 

Doubeleive

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upgrading the alternator with a standard system and no changes otherwise may have benefits such as
improved battery charging
maybe a tiny tiny bit brighter headlights and interior lighting
radio may sound slightly more crisp (questionable)
maybe less dimming when the brake pedal is applied.
ac fan might have a smidge more kick
engine "may" maybe run tiny bit better, nothing you would probably ever notice but could perhaps show up on a oscilloscope.
perhaps a .000004 hp increase from less alternator strain
that's really about it, battery health plays a big part in all of that.
 

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