My dodge is a 1991.5 which means it has an inter-cooler and over drive. I have wanted a Tachometer for a while now. I have researched this subject quite a bit, a lot of folks say that 91.5 have a factory plug taped to the wire loom under the dash. I did a lot of looking around under there and I did not find anything. There are all kinds tachs on the internet and all kinds of wild installs ranging from "I plugged it in to this extra plug and it worked perfect " to " I made a gas tach work on mine it only cost $900 and took me a year". My time and finances are limited and I don't want a tach that goes to 12000 rpm when the max I will see is 3000 rpm.
I came across this diesel only universal tach with alternator sensor on ebay for $130. The install was easy and it works. Auto Meter gives you quick connect stuff to make everything work but I opted for solder and heat-shrink. I read that the needle will go wild if you listen to the radio with the truck off (that's why i wired a switch in the power). This is not true, power draw from a sub does not affect it either. The only time I have any needle shake is when idling in gear like at a stoplight. Auto Meter recommends a 1 amp inline fuse for the supply power, this is not included. I picked one up (with a bag of 1 amp fuses) at radio shack for $5.
