Fuel gauge problem - help.

1999 Chevrolet Silverado 4.8L V8 2WD

When the truck is in park or neutral, the fuel gauge is irratic. When placed in drive or reverse the gauge stops where it was last at and then after driving, it settles out slowly to where it should be. Any takers?

I have replaced a few fuel senders that acted pretty wacko. The brushes that contact the printed circut wear down and become weak. When the fuel sloshes around, it takes up the slack in the control arm, making it register again. Chances are, it will get worse over time. The only crapper to the deal is that it is available only as an assembly, you can't get just the sender.
When I replace one because of a bad fuel pump, I always keep the old unit in case someone needs a sending unit. Since it is a used part, I don't charge the customer for parts, just labor.
I might have one in a few days. A 97, or 98 Silverado came in w/a weak fuel pump. The gauge seems to be working ok. If you're interested, let me know.
---TEX---

Chevy knows about the problem. The sensor inside the tank goes bad after awhile. My local dealer said to look for a recall pretty soon. It will be fixed at NO CHARGE.

Thats Great News, I Just Replaced Mine This Past Week 600 Big Ones

Well, I had the fuel level sender/fuel pump unit replaced and some other work done as well. I contacted the Better Business Bureau about the numerous problems I have had with the truck from 39,000 miles to 56,000 (present). Transmission, oxygen sensor, misfire cylinder 5, battery, ABS unit (EBCM), Door window regulator/motor unit, fuel pressure regulator, fuel level sending unit, and tailgate latch - WOW! Within 2 days GM contacted me and said they would assist with my current problems (Fuel pressure regulator, fuel level sending unit & ABS Module). They did and I did not purchase the extended Warranty - They paid half. They said they would have done something about the transmission at 40,000 miles, but the blew me off then and said tuff luck. It took the BBB to get results.

Replace the fuel pump assembly. I did and not only does my truck run like new, the fuel gauge is accurate! $633.32 goes to my mechanic.