Fuses and fusable links are basically the same thing. They are both a piece of conductor that is sized smaller than the wiring it is protecting and is designed to melt when overloaded.
But, when cars were first getting fuses, there were no cost effective fuses of that amperage.
The problem with a fuse is that it has to be rated for not only current but voltage. When that link melts, the electrons try to keep going, and an arc forms.
The higher the voltage, the longer the arc.
So, most fuses rated in the hundreds of amps, were for big motors or buildings and most were rated for 250 volts or more.
Which meant they had to be long enough so the melted wire gap was too long for the arc to maintain its self. Plus strong enough to handle the explosive force of a sudden discharge, and fireproof enough to handle the heat without starting a fire.
All that added up to big fuses and expensive. A fuse that size might cost $5, and you had to add in a holder of some kind.
Fusable link wire was probably a penny a foot in bulk or less. It was a no-brainer for car companies to use links.
The times they have changed though. In a chicken or egg move, somebody somewhere made a 12 volt high amperage fuse.
Much lower voltage, so it could be smaller, lighter and much less costly. Check in the fuse block of some of the modern cars and trucks, and you will see high amperage fuses.
So, if you want to retrofit your truck, feel free. Remember a fuse only protects what is downstream of it, so the closer to the battery the better.
Your next question is going to be what size fuse?
I have no idea off the top of my head. Somewhere I saw a chart giving the amperage rating of the different size fuse links, but I can't put my hand on it now.....
