B3dlam

I am looking for some information on when and if I would need to look into upgrading the alternator on my 2018 Lariat.

I plan to be installing a number of light bars as I end up doing a lot of driving down ill maintained logging roads late at night. Along with that I will be installing 'scene lights' aka floods pointing sideways to light up Base camp during sar callouts. My question is how much amperage is acceptable to draw off the stock alternator? Looking at basic light bars most draw in the 15-25A range I will also be running a VHF/UHF radio which draw around .5A in standby and 4-5A while transmitting. In theory just with aftermarket the potential draw assuming I turned everything on calculates out to ~55A. Is this going to be an issue for my truck? I don't expect to be running all of them all the time but if I was for some reason I don't want there to be any issues.

tcp2

Other than removing the sense wire for the smart charging system, I would leave it alone. The smart charging system monitors battery charging and only allows it to charge to 80(?)% to save fuel. Removing the smart charge sense wire should allow it to be fully charged when you need it and your alternator should be able to keep up.

Scott91370

If you're using LED lights the draw is so small I wouldn't even worry about it. If you shut the equipment off a few minutes before turning the truck off everything will have time to top off.
https://www.rapidtables.com/calc/ele...alculator.html

Steve Osborne

use relays...maybe an extra battery...lol...

B3dlam

Larger LED Light bars actually do draw a decent amount a 42" light bar at 240W assuming a 12v system is a draw of 20A

I plan to everything is going to be run off an AUX fuse/relay box with each system controlled individually by relays. The switches that power the relays will be add-a-fused off of an ignition cutout system so that none of the relays will turn on with the ignition off.

Z7What

You will be fine with the stock battery and stock alternator but as it was mentioned make sure each component has its own fuse and relay.

My last F150, a 03 had Two 300/2 Amps, One 500/1 Amp, One Video Amp, One Small Fan Inside The Console(To Cool Amps), Two TVs, Two 16" EFans, Three 8" Efans, Two Sets of HIDs, Five Aftermarket Gauges & A Intercooler Pump and i had no issues at all, even at idle with everything on and the radio cranked up!

My current F150, a 13 doesnt have nearly as much stuff and the electrical system is larger. Two LED, Light Bars, LED Bed Lights, Demon Eyes, HIDs, Etc No issues at all!

Wayne

B3dlam

Thanks, yeah everything is fused and relay controlled and my entire aux system is tied into the Accessory cutout so everything shuts down when I shut off the truck.

I had initially used an ignition cutout circuit but than everything shuts down whenever the auto-off engine shuts down in traffic which is less than ideal considering I regularly use the Radio when I am bored sitting in traffic.