on my '84... I was working on hooking up my aftermarket radio which is installed as to not disturb the factory radio. I decided to tap directly off the fuse block wiring to the OEM radio seeing as it is already fused (but the aftermarket radio is fused as well). So I referred to my trusty vac/electrical book for the fuse layout. I found the fuse but it had the wrong ampere fuse in it - a 7.5 amp instead of the (required) 15a fuse. So I start looking at all the fuses and I would say that 80% of the fuses are the wrong amperage, most of which are higher than they're supposed to be. Now I know this is totally wrong but why would someone change almost every fuse to a higher rating? I also took the fuse block off to trace the exact wire I needed and found a melted wire in the process (to tail lights). This circuit too had the wrong value fuse in it.

So I double checked the fuse requirements in both my owners manual AND shop manual, and they all confirm the same thing - am I losing it: is there a different fuse diagram I should be going by or should I just go by the shop manual. I know I need to get these things changed out pronto or risk a car-b-que

 

I would look at it again, and even pull a fuse that has a certain description, and make sure that part of the truck doesn't work with that fuse pulled. If you are sure you are looking at it right, then switch them all around like they should be. Someone else obviously looked at it wrong at one time or another and moved them.

 

That's a good thought! I'll do that. But there's still the 7.5 amp in the radio spot and there appears to be no factory 7.5 amp fuse in the diagram.

 

Doesn't seem unusual to me. Having owned an old pickup for awhile, sometimes when a fuse blows, you just put in whatever fuse you have lying around!

 

Yes, I can see putting in a lower amp fuse than what's required. I probably won't worry about that one, just the ones that are larger than required.