How do alternators on the GX470 fail? (3 Viewers)

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If you could buy a GX with 400 horsepower for $100 more, would you? Same concept applies to electrical power for people who have fridges, winches, dual batteries, etc.

I don't think 400 hp for $100 is an apt comparison, i.e. in terms of scale. Would I pay for a GX with 400 horsepower for $1000 more (a more appropriate comparison)? Absolute *NOT*. I'd rather spend $1000 on some other more useful feature.

Winch current draw. Good point. That's good enough reason for me.

I don't see that fridge and dual battery needs a more powerful alternator. Two to three hours on the freeway is enough to charge both with a regular alternator.
 
I have a 60A stereo (on all the time), Quickcharge Qi chargers, an iPad, dual batteries, LED lights, a 12k winch, a large ARB fridge, a full travel trailer with it's own battery, and a few other things all charging at once while hooked up. The best reason without all of the above is: 180A at 1800rpms with a 12k winch. I can get a full power pull without having to idle up, so I can pull the full capacity of the winch without revving the engine much so I stay in ATRAC range and can crawl and winch.
 
Dan. Can you recommend a place to order higher output alternator? Thanks in advance.
 
That's what I got!
 
Got the rebuilt alternator Denso 210-0512 (standard 130A) installed today. Alternator was $140 at Amazon including tax and free shipping (no core exchange). Labor was $85 at a local mechanic. I'm ready for Death Valley and Joshua Tree National Parks.

Oh, and I kept my old alternator as a spare. Is there anyway to tell when an alternator was manufactured? I'm just curious to know how old it was. It looks original to 2003.
 
My alternator just died on my 2009 with 90k miles. It gave very little warning before going out. The battery light on the dash came on about 20 mins from home. After a quick google search about what the dash battery light meant, it said it was most likely due to failing alternator. Turned off AC, radio and unplugged usb cables (as recommended by others) and headed straight home.
Was fine for 10 mins until stopped at a light and then all lights lit up on dash. Started to pull over and dash lights began to fade in and out.....then it died right there on the side of the road. Had to have it towed to my house, first time to be stranded in this truck.
81143829-04AA-4CDA-8D60-7DE281FAB206.jpeg

Tow guy tested battery, said it looked good and was most likely the alternator. Got a new Denso alternator ordered and on the way for Mr. AlohaJen to install when it gets here, and I will provide much needed cold beverage support staff duties as needed!
Kind of bummed how little warning was given before it died, but luckily mine went out 10 mins from home. Would suck to be somewhere remote and then stuck there.
 
Wow! I wasn't expecting such a quick death from the alternator and at 90k miles nonetheless.

I've replaced mine last month, so I have peace of mind now.

By the way, I was in Kailua Beach in Oahu on vacation when I got the dreaded "incoming ballistic misile....this is not a drill" alert on my iPhone. Nice welcome to Hawaii message! Good thing I thought it was a hoax since I'm from Los Angeles and I don't really know what to do on a misile attack.

Anyways, you will now have alternator peace of mind.
 
My alternator just died on my 2009 with 90k miles. It gave very little warning before going out. The battery light on the dash came on about 20 mins from home. After a quick google search about what the dash battery light meant, it said it was most likely due to failing alternator. Turned off AC, radio and unplugged usb cables (as recommended by others) and headed straight home.
Was fine for 10 mins until stopped at a light and then all lights lit up on dash. Started to pull over and dash lights began to fade in and out.....then it died right there on the side of the road. Had to have it towed to my house, first time to be stranded in this truck.
View attachment 1623240
Tow guy tested battery, said it looked good and was most likely the alternator. Got a new Denso alternator ordered and on the way for Mr. AlohaJen to install when it gets here, and I will provide much needed cold beverage support staff duties as needed!
Kind of bummed how little warning was given before it died, but luckily mine went out 10 mins from home. Would suck to be somewhere remote and then stuck there.

This sounds like what happened on my 2007. I thought was alternator. Battery tested fine. I still felt like could be battery. I replaced battery and no issues. That was over a year ago.
 
@Aloha Jen I literally just did the alternator on my wifes GX last night. We have a scanguage on it and when the voltage started to drop it started making an awful noise. Thought it was the bearings going out, but it turned fine by hand when I got it out so :meh:. Anyway, get a reman'd Denso and roll on.

Also, I know the the Mr. is very capable, but I followed this how-to I found on youtube and it went just as described. Took a leisurely 2.5 hours to knock it out.



Good luck

As far as how ours failed, it was gradual, and not all at once. I had been watching the voltage on the scanguage and it had been varying up and down but never out. About 2 weeks ago, I got a groaning whine and the voltage dropped to about 11.5, but after 30 minutes or so, voltage went back into the 12's and the sound went away. fast forward to this past Monday and the wife called and said the noise was back and seemed to be here to stay. Car never died and even started twice on the way home when she was making stops. I checked the battery when she got home. Running - 11.4V at battery, Off - 12.5V across terminals.... Put it on the trickle charger over night and still wasn't fully charged back up after about 10 hours.

Installed the new Denso Reman last night per the video and we were back at 14.1 Running.

She monitored it on her ride to work this morning and all is good. And got rid of some other odd noises that I had not traced back to the alternator, but that clearly were coming from it.
 
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Wow! I wasn't expecting such a quick death from the alternator and at 90k miles nonetheless.

I've replaced mine last month, so I have peace of mind now.

By the way, I was in Kailua Beach in Oahu on vacation when I got the dreaded "incoming ballistic misile....this is not a drill" alert on my iPhone. Nice welcome to Hawaii message! Good thing I thought it was a hoax since I'm from Los Angeles and I don't really know what to do on a misile attack.

Anyways, you will now have alternator peace of mind.

Yeah, that was such a weird morning! We are pretty isolated up here on the north shore, but I was still pretty freaked out when the message came through.

This sounds like what happened on my 2007. I thought was alternator. Battery tested fine. I still felt like could be battery. I replaced battery and no issues. That was over a year ago.
Hmmm, maybe it might be worth pulling a battery from one of the other cruisers to test it.

@Aloha Jen I literally just did the alternator on my wifes GX last night. We have a scanguage on it and when the voltage started to drop it started making an awful noise. Thought it was the bearings going out, but it turned fine by hand when I got it out so :meh:. Anyway, get a reman'd Denso and roll on.

Also, I know the the Mr. is very capable, but I followed this how-to I found on youtube and it went just as described. Took a leisurely 2.5 hours to knock it out.



Good luck

As far as how ours failed, it was gradual, and not all at once. I had been watching the voltage on the scanguage and it had been varying up and down but never out. About 2 weeks ago, I got a groaning whine and the voltage dropped to about 11.5, but after 30 minutes or so, voltage went back into the 12's and the sound went away. fast forward to this past Monday and the wife called and said the noise was back and seemed to be here to stay. Car never died and even started twice on the way home when she was making stops. I checked the battery when she got home. Running - 11.4V at battery, Off - 12.5V across terminals.... Put it on the trickle charger over night and still wasn't fully charged back up after about 10 hours.

Installed the new Denso Reman last night per the video and we were back at 14.1 Running.

She monitored it on her ride to work this morning and all is good. And got rid of some other odd noises that I had not traced back to the alternator, but that clearly were coming from it.

Thanks, that YouTube video seems like it would be very helpful when we change ours out.
 
My alternator just died on my 2009 with 90k miles. It gave very little warning before going out. The battery light on the dash came on about 20 mins from home. After a quick google search about what the dash battery light meant, it said it was most likely due to failing alternator. Turned off AC, radio and unplugged usb cables (as recommended by others) and headed straight home.
Was fine for 10 mins until stopped at a light and then all lights lit up on dash. Started to pull over and dash lights began to fade in and out.....then it died right there on the side of the road. Had to have it towed to my house, first time to be stranded in this truck.
View attachment 1623240
Tow guy tested battery, said it looked good and was most likely the alternator. Got a new Denso alternator ordered and on the way for Mr. AlohaJen to install when it gets here, and I will provide much needed cold beverage support staff duties as needed!
Kind of bummed how little warning was given before it died, but luckily mine went out 10 mins from home. Would suck to be somewhere remote and then stuck there.
There are repercussions for leaving the 80 at home...:oops:
 
There are repercussions for leaving the 80 at home...:oops:
This is true, I’m pretty sure the original alternator is still on my 1995 80 with 219k miles.
 
I had alts fail on all 5 cruisers I have owned so I PMed my GX alt to an HO 290A at 153k.
 
@DanKunz its because you overload them with too many gadgets! Lol

I still have original alternator on 96FZJ80 with 250k miles
 
If the bearings are still good, is there any reason to get a rebuilt alternator instead of just replacing the diode pack and brushes?
 
Toyota alts all fail at the bearing or at the diode/brushes. Given the relative ease to access, if your bearings are ok and you want to rebuild you could. Bearings will fail eventually and you won't have much recourse at that point, so for the time/effort I have always just swapped it. Could totally rebuild if you want to though.
 
@Aloha Jen I literally just did the alternator on my wifes GX last night. We have a scanguage on it and when the voltage started to drop it started making an awful noise. Thought it was the bearings going out, but it turned fine by hand when I got it out so :meh:. Anyway, get a reman'd Denso and roll on.

Also, I know the the Mr. is very capable, but I followed this how-to I found on youtube and it went just as described. Took a leisurely 2.5 hours to knock it out.



Good luck

As far as how ours failed, it was gradual, and not all at once. I had been watching the voltage on the scanguage and it had been varying up and down but never out. About 2 weeks ago, I got a groaning whine and the voltage dropped to about 11.5, but after 30 minutes or so, voltage went back into the 12's and the sound went away. fast forward to this past Monday and the wife called and said the noise was back and seemed to be here to stay. Car never died and even started twice on the way home when she was making stops. I checked the battery when she got home. Running - 11.4V at battery, Off - 12.5V across terminals.... Put it on the trickle charger over night and still wasn't fully charged back up after about 10 hours.

Installed the new Denso Reman last night per the video and we were back at 14.1 Running.

She monitored it on her ride to work this morning and all is good. And got rid of some other odd noises that I had not traced back to the alternator, but that clearly were coming from it.

I think we are going to attempt this today following those steps in the video link you posted. One question for you is does your GX have KDSS? If so, were there any issues with it that the video didn’t cover? Also, did you take off the power steering pulley or did you remove the whole ps pump to get the alternator out?
 
I think we are going to attempt this today following those steps in the video link you posted. One question for you is does your GX have KDSS? If so, were there any issues with it that the video didn’t cover? Also, did you take off the power steering pulley or did you remove the whole ps pump to get the alternator out?

We dont have KDSS, so I'm not sure I can help on that front. But on the power steering side, I just wedged an extension in and pulled the pulley as the video showed. That was the tightest part. The rad hose runs right in front of the pulley and makes getting a socket on it really snug, but it is doable. I did wverything from the bottom and it went fairly smoothly. Getting the belt tensioner is similar. A 12 point socket is helpful to get a better angle.
 

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