New alt and batt. Still have voltage drop

[S33k3r]

I'm having the same issue as well I've got the stock 145 and I have a nasty drop in volts when I'm doing my front windows at the same time it'll drop me from about 14 to 12 volts and dims my lights. I've got the big three done but something is going on I don't know if it's a ground or what it is but it sucks because I want to install my sound system but I can't because if I do it's going to drop even worse...

ALSO, lubricate the window guides. There's a silicon based lubricant for this. I think there may even be a mention in a YouTube video. Additionally, the power window motors may have something wrong with them -- like everything in there is dirty and simply needs to be cleaned. It sounds as if you are describing an issue where the window motors are placing an abnormally high load on the system.

 

[Squiddy1987]

clean all your grounds and upgrade to a 160amp or better, if the battery is older than 3 years buy a new one.
none of the above members have been seen for years

Thank you the battery is brand new maybe a month or too old I mean I would go into more detail I have another thread that kind of explains what's going on with my vehicle because it's all over the place and I don't know where to begin LOL.

 

[Doubeleive]

Thank you the battery is brand new maybe a month or too old I mean I would go into more detail I have another thread that kind of explains what's going on with my vehicle because it's all over the place and I don't know where to begin LOL.

well
I would start cleaning grounds all over, one thing that could also cause it is the headlights? have you noticed it happen more at night versus daytime? any headlight flickering going on?

 

[Squiddy1987]

well
I would start cleaning grounds all over, one thing that could also cause it is the headlights? have you noticed it happen more at night versus daytime? any headlight flickering going on?

Yeah I do have a lot of issues with the headlights flickering only usually if I'm using some draw of power. But I'm also having an issue with my truck being the way it is if my ABS light and my brake light are off my truck will drive normal then randomly I'll have a drop in power my RPM will drop for like a second. And then it drives normal and then it happens again but when those two lights turn on on my Dash my truck runs perfectly fine but then I'm also having an issue because when those two lights are on is when I'm having the power issues because when they're off my volt reads 14 the entire time no issues.... so close to driving this truck off a cliff..

 

[Doubeleive]

Yeah I do have a lot of issues with the headlights flickering only usually if I'm using some draw of power. But I'm also having an issue with my truck being the way it is if my ABS light and my brake light are off my truck will drive normal then randomly I'll have a drop in power my RPM will drop for like a second. And then it drives normal and then it happens again but when those two lights turn on on my Dash my truck runs perfectly fine but then I'm also having an issue because when those two lights are on is when I'm having the power issues because when they're off my volt reads 14 the entire time no issues.... so close to driving this truck off a cliff..

The ABS modules get shorted on these often but it shouldn't cause a voltage problem

 

[Doubeleive]

You can try pulling the ABS fuse. This will make the ABS light come on and you'll have just standard brakes but you can try that and see if that resolves your voltage problem if it does then great you found the problem, the module can be repaired or replaced with the exact same model number, if it does not fix the voltage issue then one of the first things I would do is get new battery cables

 

[Fless]

@Squiddy1987 What do the main battery cables (+ and -) look like? They may need to be replaced since they can rot from the inside.

 

[S33k3r]

Specifically, the positive from the alternator to the fuse block is known for rotting inside the shielding.

Also, have you tested your alternator? What you describe is lack of power under load, and you said it was 200 AMPs. Do you have access to a known, working Alternator? If so, please test this out. I don't know where you live, or I'd offer up a spare I have.

 

[Squiddy1987]

Specifically, the positive from the alternator to the fuse block is known for rotting inside the shielding.

Also, have you tested your alternator? What you describe is lack of power under load, and you said it was 200 AMPs. Do you have access to a known, working Alternator? If so, please test this out. I don't know where you live, or I'd offer up a spare I have.

I'm in Phoenix AZ it's a 145 amp it's all over the place... my rear wiper will start randomly when I would hit the brake and not turn off pulled the fuse truck has massive power draw when doing windows going to check on my lunch brake grab my volt meter.

 

[B-train]

Agreed with ^^^^^^

What is the brand of alternator? As stated, have you had it tested? I would put it past a cheaper line alternator to have internal issues. The lights flickering is a give away to me that the alternator isn't up to *****.

The ABS module draws a lot of juice, so pulling the fuse as stated above can aid in narrowing down pieces of the system that may be the culprit