What did you do to your OBS GMT400 Tahoe/Yukon Today?

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fastpat

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@SunlitComet - I just purchased the Flex A Lite 280 dual electric fan bolt on kit for my 99 Hoe with the 5.7L V8. I know the manufacturer writes the unit draws up to 28 amps. I was thinking this might also be a good time to upgrade my alternator from the stock 105 amp to at least a 140 amp unit. Yes? No? Any suggestions on a make/model I should go with?

I also would like to know if you think I should upgrade the battery cables and the power cable from the battery to the alternator with thicker gauge cables - a 2 gauge? 4 gauge? I just want to make sure I don't burn up my electrical system by adding this dual electric fan set-up and I'm supplying the power the system needs, especially when the vehicle is running at idle with the AC on max and maxed out fan speed in the summer heat in Phoenix!

Thanks!

What is your voltage reading now? After the battery is recharged from the draw down of starting the truck, it should settle on 13.8 volts plus or minus a few tenths. I'm installing a fresh battery today and have a 200 amp alternator on order. I don't need 200 amps, but wanted the 100 amps available at idle.

It was 95º here yesterday afternoon and the A/C ran out of cold while idling, indicating I may need a set of aux fans, too. We'll see.
 
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Hello @fastpat .. yes, I sit at right about 13.8 amps on the gauge upon start-up and idle and it drops down to about 12.5 to 13 when I turn on my car stereo (stock), LED headlights and AC on max speed recirc all at once. That's really the only major combo power draw I currently have. I figure the FLA 280 will drop it down to around maybe 10 or 11 so I want to be prepared with a higher output alternator. I did upgrade my battery recently to the mega deluxe model at Auto Zone (that sucker was about 200 bucks!).
 

DallasTahoe

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Hello @fastpat .. yes, I sit at right about 13.8 amps on the gauge upon start-up and idle and it drops down to about 12.5 to 13 when I turn on my car stereo (stock), LED headlights and AC on max speed recirc all at once. That's really the only major combo power draw I currently have. I figure the FLA 280 will drop it down to around maybe 10 or 11 so I want to be prepared with a higher output alternator. I did upgrade my battery recently to the mega deluxe model at Auto Zone (that sucker was about 200 bucks!).

I’ve got a 140 amp alt and I upgraded my wiring to 0 gauge grounds, and power cables. With everything on including 3 pairs of auxiliary lights and efans and and 4hi mod at idle I’m at about 13.7-13.9. Of course I do have a second battery as well


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fastpat

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Hello @fastpat .. yes, I sit at right about 13.8 amps on the gauge upon start-up and idle and it drops down to about 12.5 to 13 when I turn on my car stereo (stock), LED headlights and AC on max speed recirc all at once. That's really the only major combo power draw I currently have. I figure the FLA 280 will drop it down to around maybe 10 or 11 so I want to be prepared with a higher output alternator. I did upgrade my battery recently to the mega deluxe model at Auto Zone (that sucker was about 200 bucks!).

If your wiring, battery, and alternator are all in good condition or better; you shouldn't have that kind of voltage drop. For your issue I'd recommend you upgrade your alternator to battery cable, either to 2 gauge or 0 gauge. I'd also recommend you remove and replace your under hood ground straps, cleaning off the ground attachment points on both ends.
 

07Burb

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Looking fresh, the white tripped me out as well, good to know that’s how some are coming now-a-days. And gotta ask what is all this stuff in the red circle?
View attachment 203724
Yep, just garbage from the previous owners. Like @Galante said, caked up grease (grease zirk is under there somewhere), road grime and debris....I had to knock a bunch of that crap off while i was in there. I never did get it perfect because I'll be doing ball joints here really soon anyway and it'll take care of itself then. The previous owners of this thing must have lived on a dirt road and never cleaned a thing. There's crap like that every where underneath this thing. I'm gradually getting it all cleaned up but it would take me a solid week to truly get it all clean if I didn't have a job I had to come to every day LOL
 
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