145 amp alt?
http://i16.ebayimg.com/01/i/000/7f/af/ca8c_1.JPG
http://i15.ebayimg.com/07/i/000/7f/af/caeb_1.JPG

 

go hold it up to the one on your truck now. If its bigger its the 145 amp

 

.......

 

you cant really tell by looking at it that far away

here is a pic of where it would say what it is, it will be stamped on there what it is , 105A OR 145A or whatever size it is

EDIT: i went and took a pic of mine (105A) and traced over the "105A" so it is more visible

 

as stated above, the most obvious way to tell is where it's etched in the case. It's slightly larger (and requires a different belt) also. If it wasn't raining out I'd go get a shot of both of mine side by side for you, but it's cold and wet and I'd rather stay inside where it's nice and warm

 

Looks like a bigger case the 105 is regular and the 145 has the middle place piece in it.

 

Yep. The 105 not cutting it? Back when I had my old truck I murdered a few 105's with my extra lights and stereo system. I went to the 140 and it never died.

I'd assume your service id tag should say which alt you have.

 

not yet but i have a nice size amp smaller than before (which was killing it) and Electric fans. i have a 105 on mine.

 

btw plugin doesnt look like mine...

 

I had to get an adaptor harness from ohio generator. this was years ago, don't even know if they still sell adaptors.