Peterbilt 387 Fuel Gauge Problem

I use a yard stick. Never fails

 

Replaced the sending unit, it still acts kinda screwed up, got a new gauge just haven't put it in yet. This may be a dumb question but how do you all interpret the fuel gauge and how to read it to determine what you have in the tank, looks like 8th's instead of quarters if anyone is following my jacked up explanation..

 

The gauge is in quarters an in eighths. If its messing up just keep track of your fuel economy if u know u drive 1200 miles and it takes 180 gallons and u can hold 240 don't go over 1200 miles and you'll never run out and have some left for emergencies

 

Did you check your power and ground at the weatherpack connector? Some models of Pete and KW will actually have two in the harness... there'll be one which connects to the fuel sending unit itself, then there'll be another one a few feet down which ties into the actual harness. Don't ask me the rhyme or reason for it... I don't know. But I'd check the condition of those terminals.