The fix for my endless alternator failure's
Just did the swap yesterday and very happy with the results! I went with a new Tuff Stuff GM AD244 145 amp alternator (PT#8237) from Summit Racing. It was $135 w/ free shipping. The install was pretty straight forward and it mounted up perfectly after wiggling it up between the fan and sway bar. The voltage needle jumped right out of the red and stayed solid at 13.5. Overall I couldn't be happier, thanks for the help! 
Has anyone found out Vette guys can use the truck alternator? I know it won't fit, just wondering if there is a bracket anyone has made to make the truck alternators fit with corvette accessories.
On The Tree
Joined: Jul 2006
Posts: 167
Likes: 0
From: tx
On The Tree
Joined: Jul 2006
Posts: 167
Likes: 0
From: tx
Using a 2003 tahoe alternator and 1998 PCM.
we read this thread and not really sure if we need a 470 ohm resistor or not. also read where someone jumped terminal "S" to the positive lug on the alternator.
we were told to connect it the way we have it now and we get no charge.
(only reading 11 volts).
we connected; "L" terminal to brown wire to PCM and "I F" terminal to pink wire to ignition hot.
wanting to make sure we are connecting this correctly.
we read this thread and not really sure if we need a 470 ohm resistor or not. also read where someone jumped terminal "S" to the positive lug on the alternator.
we were told to connect it the way we have it now and we get no charge.
(only reading 11 volts).
we connected; "L" terminal to brown wire to PCM and "I F" terminal to pink wire to ignition hot.
wanting to make sure we are connecting this correctly.
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Ok, I am back into this now. A little over 3 years ago I swapped the stock alternator which was showing early signs of failing with a LKQ $50 Escalade alternator and it has worked great...until this morning. It finally died. Given I am not certain of the mileage of history and that it was from an 06 iirc, I can't complain.
I still have the stock Camaro unit as well. The local alternator rebuild shop said they can pull 150-160 amps out of the stock unit or just do a stock rebuild on the Escalade unit for basically the same price. Has anyone just had a quality rebuild done on their stock unit? What were your results?
The cost of the rebuilds is about $20 cheaper than a lifetime warranty unit from any of the auto parts stores which seem to be a crap shoot.
Which would you have rebuilt to put back on?
I had enough trouble the first time around finding and OEM alternator on a junkyard vehicle vs an auto parts store reman that was taken off of a truck, escalade, etc that I don't want to go that route again.
I still have the stock Camaro unit as well. The local alternator rebuild shop said they can pull 150-160 amps out of the stock unit or just do a stock rebuild on the Escalade unit for basically the same price. Has anyone just had a quality rebuild done on their stock unit? What were your results?
The cost of the rebuilds is about $20 cheaper than a lifetime warranty unit from any of the auto parts stores which seem to be a crap shoot.
Which would you have rebuilt to put back on?
I had enough trouble the first time around finding and OEM alternator on a junkyard vehicle vs an auto parts store reman that was taken off of a truck, escalade, etc that I don't want to go that route again.
Joined: Sep 2004
Posts: 3,148
Likes: 12
From: Downers Grove, IL
Using a 2003 tahoe alternator and 1998 PCM.
we read this thread and not really sure if we need a 470 ohm resistor or not. also read where someone jumped terminal "S" to the positive lug on the alternator.
we were told to connect it the way we have it now and we get no charge.
(only reading 11 volts).
we connected; "L" terminal to brown wire to PCM and "I F" terminal to pink wire to ignition hot.
wanting to make sure we are connecting this correctly.
we read this thread and not really sure if we need a 470 ohm resistor or not. also read where someone jumped terminal "S" to the positive lug on the alternator.
we were told to connect it the way we have it now and we get no charge.
(only reading 11 volts).
we connected; "L" terminal to brown wire to PCM and "I F" terminal to pink wire to ignition hot.
wanting to make sure we are connecting this correctly.
I know your using a 98 PCM and 2003 alt, but what year is your harness? I thought that the 98 f-body harnesses only had a red wire on the alt connector but yours has a pink and brown wire?
On The Tree
Joined: Jul 2006
Posts: 167
Likes: 0
From: tx
I can`t seem to find much good info on the regulator in the newer alt, but I think that if you connect the L terminal to a resistor or light bulb and then to +12v and then connect the S terminal to 12v it should work.
I know your using a 98 PCM and 2003 alt, but what year is your harness? I thought that the 98 f-body harnesses only had a red wire on the alt connector but yours has a pink and brown wire?
I know your using a 98 PCM and 2003 alt, but what year is your harness? I thought that the 98 f-body harnesses only had a red wire on the alt connector but yours has a pink and brown wire?
And you are correct only one(RED) wire from the pcm
To the connector, for some strange reason we changed the color to brown when we spliced in longer length wire. We're getting no voltage at the Red wire from the pcm side , are we supposed to? Not sure what the red wire is doing for the pcm. And are you saying to just not use the 98 harness red wire, instead run a wire (with resistor ) to ign+ (along with another ign+ to S terminal). Btw, I have read that jumping the S terminal to the alt hot lug is not actually correct, Instead The S terminal should connect at a bus bar or fuse box downstream to get an true reading.
which one of the connections is actually exciting the alternator to turn on?
I ended up picking one up from the Junkyard for $10 as it had a bad regulator on it. I rebuilt mine with a silver plated Rectifier bridge containing upgraded diodes of 70amp each instead of 50amp each, Upgraded Voltage regulator that pulls its power strait from the alt post, instead of a little soldered piece like stock, used silver solder on the post, stator crimps and voltage regulator bridge crimp. Upgraded and replaced both bearings inside, cleaned the Stator contacts (they actually dont touch) inside the case with sand paper, and the brass post where the brushes ride. I am very happy with the upgrade, it is much better then taking a crap shoot with one strait out of the junk yard, especially cause i now know that i have superior parts and the work was done right.
I have included some pictures for reference. the first one shows the old vs new, and the rest are just close ups of the new one installed and work done.
I have included some pictures for reference. the first one shows the old vs new, and the rest are just close ups of the new one installed and work done.
Launching!
Joined: Oct 2010
Posts: 286
Likes: 1
From: covington ga
I wanted to contribute my experience in case it'll help someone with similar issues.
I never suspected an alternator problem at all. It had the normal light flicker but no dummy lights were on and the volt meter showed output in the norm. I had a motor built and installed with a 25% under drive. The day I go to pick it up after it was ready the builder told me to bring a battery(it was at his shop for a year and the old one **** out). So i grab a very well known good battery, get there, remove his optima and install my everstart. The car cranks, starts, dies. Tried several times with the same results.
The car didn't do that with his optima at all. We both look at each other sorta funny and he says just take his battery and order an optima. The car had to come back after a brake in to re-tune anyway. So I did just that. Broke the car in, installed a brand new optima, took it back. All's been sorta well since.
Except, the car would start and run fine, but die once you drop it in gear. This went on for over a year, almost two years now. I was just slam fed up and decided something was wrong. Well. My builder did mention something about the alternator was getting weak way back when. I figure well it still works so whatever.
Enough was enough though. I found this thread, went by a junk yard and picked up the famous $50 upgrade. My install was a little more complicated, I had a lq9 installed and had to tap the missing hole in the block in the car (what a pain). I fired it up AND.............
Problem solved. I did everything as usual and it NEVER died. I even tried to make it stall and it wouldn't. Just amazing how awesome this upgrade is. Maybe my alternator was one leg in the garbage and just having a fresh one is all it needed. I don't have the light flicker anymore, it doesn't stall, just fantastic. I'm tickled pink. Thank you so much for this thread.
I never suspected an alternator problem at all. It had the normal light flicker but no dummy lights were on and the volt meter showed output in the norm. I had a motor built and installed with a 25% under drive. The day I go to pick it up after it was ready the builder told me to bring a battery(it was at his shop for a year and the old one **** out). So i grab a very well known good battery, get there, remove his optima and install my everstart. The car cranks, starts, dies. Tried several times with the same results.
The car didn't do that with his optima at all. We both look at each other sorta funny and he says just take his battery and order an optima. The car had to come back after a brake in to re-tune anyway. So I did just that. Broke the car in, installed a brand new optima, took it back. All's been sorta well since.
Except, the car would start and run fine, but die once you drop it in gear. This went on for over a year, almost two years now. I was just slam fed up and decided something was wrong. Well. My builder did mention something about the alternator was getting weak way back when. I figure well it still works so whatever.
Enough was enough though. I found this thread, went by a junk yard and picked up the famous $50 upgrade. My install was a little more complicated, I had a lq9 installed and had to tap the missing hole in the block in the car (what a pain). I fired it up AND.............
Problem solved. I did everything as usual and it NEVER died. I even tried to make it stall and it wouldn't. Just amazing how awesome this upgrade is. Maybe my alternator was one leg in the garbage and just having a fresh one is all it needed. I don't have the light flicker anymore, it doesn't stall, just fantastic. I'm tickled pink. Thank you so much for this thread.
Last edited by jsmith564; Dec 10, 2013 at 09:16 PM.
Connect your exciter wire (that's the brown wire in your picture) to a wire that powers up when you turn the key on, not full time hot like the alternator lug, to terminal L (again your brown wire)
On my car when I had the code on for terminal L malfunction it would not send a signal out of the computer to the terminal/connector, and if you try to test the wire with the connector disconnected the computer picks up on the fact that it is disconnected right away and resets the code and will disable the signal and confuse the **** out of you. I do not know how the two wire system works, but as far as the alternator it just needs a hot signal into L terminal to excite the alternator. If you want to test this out just tap into the brown wire with a positive feed and start it up, if the alternator works it will charge.
You really shouldn't need a resistor or bulb, that terminal just needs to see + power to excite the alternator, the terminal doesn't really know that there is resistance in the bulb. The car's computer would look for resistance to know if there is a fault, so if you were concerned about what the computer sees then I would do a bulb or resistor, but just to get the alternator to come on it is not necessary.
If you hard wire the brown wire to a switched hot just get rid of that pink wire. The computer does regulate the signal out to the alternator so if you run a hot wire to terminal L the alternator will stay on, but that's not a big deal. They pretty much run all the time anyway. All the cars I worked on from the 70's up through the 90's when they started regulating voltage kept the exciter wire on full time. That regulating the alternator on and off started some where in the late 90's in an effort to reduce parasitic drag and increase fuel mileage.
On my car when I had the code on for terminal L malfunction it would not send a signal out of the computer to the terminal/connector, and if you try to test the wire with the connector disconnected the computer picks up on the fact that it is disconnected right away and resets the code and will disable the signal and confuse the **** out of you. I do not know how the two wire system works, but as far as the alternator it just needs a hot signal into L terminal to excite the alternator. If you want to test this out just tap into the brown wire with a positive feed and start it up, if the alternator works it will charge.
You really shouldn't need a resistor or bulb, that terminal just needs to see + power to excite the alternator, the terminal doesn't really know that there is resistance in the bulb. The car's computer would look for resistance to know if there is a fault, so if you were concerned about what the computer sees then I would do a bulb or resistor, but just to get the alternator to come on it is not necessary.
If you hard wire the brown wire to a switched hot just get rid of that pink wire. The computer does regulate the signal out to the alternator so if you run a hot wire to terminal L the alternator will stay on, but that's not a big deal. They pretty much run all the time anyway. All the cars I worked on from the 70's up through the 90's when they started regulating voltage kept the exciter wire on full time. That regulating the alternator on and off started some where in the late 90's in an effort to reduce parasitic drag and increase fuel mileage.
Last edited by 00pooterSS; Dec 23, 2013 at 03:32 AM.
I wanted to contribute my experience in case it'll help someone with similar issues.
I never suspected an alternator problem at all. It had the normal light flicker but no dummy lights were on and the volt meter showed output in the norm. I had a motor built and installed with a 25% under drive. The day I go to pick it up after it was ready the builder told me to bring a battery(it was at his shop for a year and the old one **** out). So i grab a very well known good battery, get there, remove his optima and install my everstart. The car cranks, starts, dies. Tried several times with the same results.
The car didn't do that with his optima at all. We both look at each other sorta funny and he says just take his battery and order an optima. The car had to come back after a brake in to re-tune anyway. So I did just that. Broke the car in, installed a brand new optima, took it back. All's been sorta well since.
Except, the car would start and run fine, but die once you drop it in gear. This went on for over a year, almost two years now. I was just slam fed up and decided something was wrong. Well. My builder did mention something about the alternator was getting weak way back when. I figure well it still works so whatever.
Enough was enough though. I found this thread, went by a junk yard and picked up the famous $50 upgrade. My install was a little more complicated, I had a lq9 installed and had to tap the missing hole in the block in the car (what a pain). I fired it up AND.............
Problem solved. I did everything as usual and it NEVER died. I even tried to make it stall and it wouldn't. Just amazing how awesome this upgrade is. Maybe my alternator was one leg in the garbage and just having a fresh one is all it needed. I don't have the light flicker anymore, it doesn't stall, just fantastic. I'm tickled pink. Thank you so much for this thread.
I never suspected an alternator problem at all. It had the normal light flicker but no dummy lights were on and the volt meter showed output in the norm. I had a motor built and installed with a 25% under drive. The day I go to pick it up after it was ready the builder told me to bring a battery(it was at his shop for a year and the old one **** out). So i grab a very well known good battery, get there, remove his optima and install my everstart. The car cranks, starts, dies. Tried several times with the same results.
The car didn't do that with his optima at all. We both look at each other sorta funny and he says just take his battery and order an optima. The car had to come back after a brake in to re-tune anyway. So I did just that. Broke the car in, installed a brand new optima, took it back. All's been sorta well since.
Except, the car would start and run fine, but die once you drop it in gear. This went on for over a year, almost two years now. I was just slam fed up and decided something was wrong. Well. My builder did mention something about the alternator was getting weak way back when. I figure well it still works so whatever.
Enough was enough though. I found this thread, went by a junk yard and picked up the famous $50 upgrade. My install was a little more complicated, I had a lq9 installed and had to tap the missing hole in the block in the car (what a pain). I fired it up AND.............
Problem solved. I did everything as usual and it NEVER died. I even tried to make it stall and it wouldn't. Just amazing how awesome this upgrade is. Maybe my alternator was one leg in the garbage and just having a fresh one is all it needed. I don't have the light flicker anymore, it doesn't stall, just fantastic. I'm tickled pink. Thank you so much for this thread.
Last edited by 00pooterSS; Dec 23, 2013 at 03:18 AM.
You really shouldn't need a resistor or bulb, that terminal just needs to see + power to excite the alternator, the terminal doesn't really know that there is resistance in the bulb. The car's computer would look for resistance to know if there is a fault, so if you were concerned about what the computer sees then I would do a bulb or resistor, but just to get the alternator to come on it is not necessary.
Well, my first Escalade alternator has failed after 2 or 3 years. Without knowing the original mileage I can't say if I got my money's worth out of it or not.
I'm looking at eBay for other used ones since I don't have time to hit the local yards. Has anyone verified that up to '04 or even '05 will fit? Mine is from and '03 at the moment.
I'm looking at eBay for other used ones since I don't have time to hit the local yards. Has anyone verified that up to '04 or even '05 will fit? Mine is from and '03 at the moment.