70 amp alternator identification

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Jeff O

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My belt was making nosie which a shop said was bad alternator. My Tahoe had 70 amp from factory. Suspect alterntor was not the problem, only the belt, and I think they might have replaced original with lower capacity. How can I tell what is now installed?
 

Fless

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It would help us to know what year, make, model, and engine you're driving. 70A seems kind of low for OE, and replacing with even lower is likely impossible.

Post a pic of your RPO codes from the glovebox. The OE alternator code is one of those and members here can decipher them.

Also post a pic of the current (pun intended) alternator; sometimes the amp rating is etched into the alternator housing.
 

rockola1971

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It would help us to know what year, make, model, and engine you're driving. 70A seems kind of low for OE, and replacing with even lower is likely impossible.

Post a pic of your RPO codes from the glovebox. The OE alternator code is one of those and members here can decipher them.

Also post a pic of the current (pun intended) alternator; sometimes the amp rating is etched into the alternator housing.
Yup, the amp output is almost always on the alternator housing. Depending on how its clocked in the bracket it will be visible form the top or slightly off to the left or right from the center of top. Most of the time it takes a damp paper towel to remove the grime so it can be read. But a wet finger and rubbing it will do! :p
 

Doubeleive

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ya 70amp is pretty much unheard of, the lowest I have ever seen is like 90a maybe, most of these trucks are 105a bare minimum 145a is common and 160a on the higher trims
usually the part number label gives it away
105.jpg
 

rockola1971

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ya 70amp is pretty much unheard of, the lowest I have ever seen is like 90a maybe, most of these trucks are 105a bare minimum 145a is common and 160a on the higher trims
usually the part number label gives it away
View attachment 438952
You are absolutely correct concerning the amp values. The alternator pictured is either an aftermarket or rebuilt unit. GM didnt put stickered labels on the alternators of our generation. The amp output was always stamped into the housing.
 
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Jeff O

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It would help us to know what year, make, model, and engine you're driving. 70A seems kind of low for OE, and replacing with even lower is likely impossible.

Post a pic of your RPO codes from the glovebox. The OE alternator code is one of those and members here can decipher them.

Also post a pic of the current (pun intended) alternator; sometimes the amp rating is etched into the alternator housing.
After some personal research, I see that the 70 Amp figure quoted by mechanic is bogus. I have translated all of my RPO codes in the past. There isn't any specifying the alternator.
The engine is 5.3 flex fuel & Body is LT with these packages
Z82 : TRAILER PROVISIONS, SPECIAL EQUIPMENT, H.0.

1SM : PACKAGE - OPTION 12 OPTION PACKAGE #12

1SZ : PACKAGE OPTION- ?
I don't know what these are, but possibly the alternator spec is part of the towing addons.

Maybe you can determine something from that. Pics of alternators on various parts providers don't seem to indicate any external clues. I'll see if a label is visible.
I'll get a pic if none of this helps.
TNX, Jeff
 

Fless

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After some personal research, I see that the 70 Amp figure quoted by mechanic is bogus. I have translated all of my RPO codes in the past. There isn't any specifying the alternator.
The engine is 5.3 flex fuel & Body is LT with these packages
Z82 : TRAILER PROVISIONS, SPECIAL EQUIPMENT, H.0.

1SM : PACKAGE - OPTION 12 OPTION PACKAGE #12

1SZ : PACKAGE OPTION- ?
I don't know what these are, but possibly the alternator spec is part of the towing addons.

Maybe you can determine something from that. Pics of alternators on various parts providers don't seem to indicate any external clues. I'll see if a label is visible.
I'll get a pic if none of this helps.
TNX, Jeff

A few RPO codes:

K68 = 105a generator (alternator)
KG3 = 145a
KG8 = 130a
 

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