Awesome thank you. I've always wondered that. Gonna take the truck for a test run soon. Will see how she performs.
Vortec alternator upgrade
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Awesome thank you. I've always wondered that. Gonna take the truck for a test run soon. Will see how she performs.
RawbDidIt
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Your probably right, what I'm saying is that the only way to know you're acting on accurate information is to verify it. Either way, there's a few reasons you may be seeing this activity. You may not have a big enough alternator, your current alternator (no pun intended) may be on it's way out, you could need a wiring upgrade, or your battery may not be keeping up with the load. All of these options are able to be diagnosed with a multimeter, and none of them are diagnosable with the dash gage.
You need to verify voltage across the battery terminals, and across the alternator to see which it is. I made a video about this as a school project, let me dig it out.
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Awesome. I'll look into it thank you. Alt brand new btw. Got a powermaster.
As a Suburban owner with factory wiring and 105A alternator, this wouldn't worry me. Mine doesn't drop quite that low but when both A/C systems are blasting and all the lights are on I'm in the same ballpark. The blowers draw quite a bit of amperage.
Awesome I appreciate that lol. That's exactly what I did as a draw test. Blasted both ac max cold. All lights on including aftermarket foglights , wipers high and radio on. I guess I wanna see as a comparison what the new big 3 or 5 will show afterwards. Kinda like a before and after. But owning a suburban I figured her draw gonna be still significant. I'm not really worried about my alt since it's new and better then my 105 old one. But you never know what sneaks up. Domino effect..smh
BUT let me just throw out there that your gauge might not be actually representing the load, either. I am pretty confident that I have a bad ground in my dash cluster wiring: when I turn on my parking lights, my volt gauge deflects quite a bit (2 volts?) and I thought, “oh wow, I wonder if I have a short in the parking light circuit for it to be drawing that much current”. A check with a multi meter says: no change in voltage at battery at all.
So long story short: all investigation of charging system function really needs to start with a reliable volt gauge at the battery terminals.
Definitely I agree. Facts are everything. I've noticed mine twitches with the signals. And moves as the draw gets higher. I take the guage with a grain of salt. Long as it's not touching red and long as the motor doesn't start to hesitate or studder when my acc are on. For the 23 yrs we've owned it I guess I've gotten use to what it was normally doing vs all of a sudden doing something else lol. I just know everybody heres knows more about the system then I do and just wanna make sure its not a warning for something I need to do asap. This is my everyday vehicle and dont wanna get a tow once a week lol. Wife would blow a gasket if extra crap pops up.
L31MaxExpress
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I had the factory 140a on the Express. It would dip to 10-11v at idle and not recover back to 13-14 until it was driven at speed a few miles. Was killing batteries ever couple of years from the extreme cycling and would often start really weakly after only driving locally for a couple days. 105a on a dual air truck would not cut it. My 99 Tahoe had the 140a option because it was a LT model with rear air, heated leather seats and heated mirrors. Never really dipped as low as the van, but the van had almost 40a of extra load from the conversion package with interior lighting, TV, VCP, rear radio and the rear video screens in the front seats on. Add the load of a large trailer to either, with electric brakes, hooked to a pair of half discharged deep cycle trailer house batteries and it was even more unhappy. Fixed the Van with the 200a and the Tahoe with dual AD244 145s and a secondary house battery on both the Van and Tahoe. 2nd battery is in the factory driverside tray on the Tahoe and the vans 2nd battery is in a 6.5 Diesel van auxiliary battery tray on the frame. I moved all the vans interior lighting and conversion load minus rear a/c blower to the 2nd battery along with the trailer power circuit and charge the 2nd battery through a GM auxiliary battery relay. Van also has a hard wired 3,000 watt inverter. Tahoe has the 2nd battery powering the sound system, a 3,000 watt hard wired inverter and the trailer power connector. The Tahoe has 2 separate charging systems that function independently from each other but are tied together when the Tahoe is running via a GM auxiliary battery relay. When parked with the trailer connected to the Van or Tahoe the trailer has 3 deep cycle batteries to power it. It was a pain but never can have enough juice when you camp off the grid at times in scenic locations. I moved the conversion van load to the 2nd battery in the van because it is nice to have interior lighting and be able to watch the news or whatever you want to do without killing the starting battery. I have taken a few trips with the van only and few with the trailer. Taken the Tahoe on a couple of shorter local trips with the trailer too.
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If push comes to shove I'll one day add a second battery. I really prefer not to add one since I'm not running that kind of draw. But it sounds really cool. I'm sure my new alt should be big enough considering its producing more power lol.. but we'll have to see in time of course. For sure I'll keep everything you told me in mind. In case I have to do some drastic changes.
It can and does. My Suburban is a decked out LT model with pretty much every option available in '97 including rear A/C, but it came with the 105A alternator. I admit I also thought that was unusual but it's been fine for 23+ years. That truck has only had one alternator replacement and two battery replacements in its' entire life so far, and one of the batteries was killed by my stupidity.
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