Our 99 2-door Blazer gas gauge has been going crazy now that it's getting colder outside.

It started to do this last year but once it got warm we forgot all about it, but now it's back.

Is this an "easy" fix or will it have to go in to the shop? I dont have the means to drop the tank. Everything else is working, can always go with watching the trip odometer if it's something expensive.

Thanks

 

The fuel level sending unit can be replaced independent of the fuel pump itself, but the tank has to be dropped and the fuel pump assembly removed in order to replace the sending unit.

The link below will run you through the checks to perform to verify that the sending unit is at fault:
98+ Fuel Gauge Diagnosis

If you do find the sending unit is at fault and replace it, you will likely find that the little fingers attached to the float arm that wipe across the resistor grid are either broken completely off or worn down considerably. To prevent this in the future, run a bottle of Chevron Techron Fuel System Treatment Plus through at every oil change. It has a filmer agent in the mix that will protect the sending unit from the harder elements in the fuel like sulfur.