So I've got a stumper. I sent out the original fuel sender/pickup to get refurbished. I got it back, and it had instructions to raise and lower the sender float by hand to verify that it was working properly. As instructed, we tested the floater, and the gauge needle went up and down. So we button everything up, get the sender and tank in, and initially only fill it with about 4 gallons. Gauge still shows "E" but we figured that's a fail-safe to keep the driver from running out of gas. So later on, I put about another 13 gallons in. After I do that, the needle swings WAY past F, and then back down to E, even though I know I have the tank about 3/4 full. I've emailed the sender unit guy for help, but wondering if any of you had a similar experience or suggestion in the meantime. Thanks.