I was under the dash today troubleshooting my overdrive button not working when I spotted a sticker placed on the computer. I took the cover off the computer and there is a large sticker wrapped all the way around it that says "diablosport" and it's got a website address of
www.diablosport.com. I went to the website and it was a performance parts supplier and they do sell stuff for diesels. Anybody know what I should look for as to what exactly might have been done to my truck in a past life?? I'm thinking it might have a plug in port someplace for a tuner, or a chip...I have no idea what to look for though

...any ideas? Do you think I already have a chip or something and didn't know it? Thanks!