When I bought my '99 F250 7.3L, the fuel gauge was pegged on F no matter what. I did some research and found out it's most likely a stuck sending unit in the fuel tank and maybe some additives might help free it up.

Well, I knew I was pushing it based on the 42x miles I had on my last full tank, so I stopped in to fill 'er up... 26.5 gallons (29 gal tank). Now I know my approx range!

I drove to my doctor appt with it still pegged on F. When I got out of there, the low fuel light was on and it was pegged the opposite way! Talk about a finicky system. Must be female...

I dumped in some Diesel Kleen with lubricant last night... the engine was MUCH peppier. Maybe the octane boost??? Anyways, I'm hoping a day or two soaking will break things loose. I'm not looking forward to dropping the tank and performing surgery. I wish they had an access plate in the bed or design it so the tank doesn't have to be dropped to replace things.

In the words of Buddy from Night Court... "but I feel much better now"

Tim.