Hey guys hopefully im in the right place. so here goes we just added a new truck to our fleet its a 2006 ford f-550 superduty flat bed tow truck with a brand new crate 6.0 the truck has 240,xxx mi on it.

Anyways the first two weeks things were great. One day i loaded a car on the interstate everything went great when i got back into the i put it in gear and accelerated pretty hard in order to merge into the interstate in a short amount of space. When i pressed the peddle in revved out first gear perfectly when all the sudden the gauges all dropped to the bottom and the truck shut off instantly. I pulled it back into the shoulder we checked all of the fuses to find fuse 45 a 10 amp fuse was burned. I replaced the fuse and it popped right away so i put a jumper wire in and the truck started up.

I immediately pulled the truck off the interstate into a parking lot and removed the jumper and put a fuse back in its place. Since then things have been fine no problems then all the sudden i have a battery light. I replaced the alternator everything was fine a week later a battery light again. once again i replaced the alternator about four days later the light came back on.

I replaced the alternator again and this time the light stayed
but the truck was charging just fine. Then it started charging on and off the two wire connector in the back of the alternator the green and red wire while running is showing good voltage until it stops charging then its only showing 1.7v and the other is showing good voltage always

I have searched high and low but cant find any shorts any suggestions on where to look what to check would be greatly appreciated thank you guys

 

buying these alternators from pep boys or autozone? Remans?

What is the amperage of the alternators?

 

It is a single altenator truck 110 amps and i have been getting them from churchs auto parts. Each time i got a diffrent brand

They were all brand new

 

I think you should have a heavy duty alternator. Might try OEM as well. Seems the remans don't last as well.

In addition for a tow truck you are running a lot of electrical.

 

I called the local dealer and they said that the 110 anp is the only one availble. Nobody offera a higher amp except for dc which are kinda pricey but i may have to just suck it up and order it. My main concern is the random voltage drop in the green and red wire. Would the unit failing cause that type of voltage drop ??