The positive wire coming from the alternator to the power distribution center has corroded and is failing I need to replace it but haven’t been able to find the gauge of the wire and could use some help. 2001 dodge ram Laramie slt 5.9 magnum

 

Go to your local parts store, take the old one with you, get something the same size, or LARGER.....

 

Keep in mind, th gauge and size are inverse related. The smaller the number, the larger the wire. Think of it as how many to make a certain size. 2 2 gauge will be as thick a cable as 16 16 gauge.

 

Also the amp of the alternator and the length of cable play into it. A description here. I believe it is either 4 or 6 gauge. Most of the parts stores carry thinner gauge 10-18 so you may have to visit your local home improvement store. And don't forget the lugs.

 

Measured that cable on my '95 diesel, and it seems to be 3 AWG, according to diameter, which was roughly 6 mm.

 

That seems really tiny considering the current it carries......

 

I don't know about that. 3 seems like an odd number. Usually you see 2 or 4 gauge. 2 gauge is some serious wire. Anything heavier and you have welding cable. I've got some jump cables that are 2 gauge.

 

Look at the chart in the link above, It gives you the gauge wire for amps and length. About a 5 foot run at 125 amps.

 

I thought alternator cables were around 6 gauge. Jump cables shouldn't be anything less than 2 gauge in my opinion, unless you're using them on a lawn mower

 

I had a pair of 30 foot jumper cables made out of welding cable. Heavy as lead but they worked great. At least until they grew legs and walked off.