Be aware that though popular the diode solution does have a down side.

There is about a 1/2-volt drop across the diode, and this means the alternator is not correctly reading the battery's charge.

As a result you could have some battery issues. I'd not expect it to be a problem if you don't drive the truck much. If you use the truck frequently I'd expect it to decrease battery life because the battery is always being over-charged.


1955 1st GMC Suburban | 1954 GMC 250 trailer puller project | 1954 GMC 250 Hydra-Matic | 1954 Chevy 3100 . 1947 Chevy COE | and more...
It's true. I really don't do anything but browse the Internet looking for trouble...