Hi. I recently changed my alternator on my 97 police engine. Most of those take a 175 amp alt, but I was told because I didn't have all the extra stuff that police use, I didn't need one that big. I bought the 135 amp. Now I'm having issues with my battery charging, and it's a brand new battery. I had a test done, and the alternator is reading 13.8, but I'm still having issues. Could it be that I do need the 175? I've checked the connections and they all seem to be good. Please help?