When i first bought the truck in the winter, the speedometer didnt work at all, as the weather got warmer, it began to work, now it doesnt work at all. It isnt a fuse, i've checked them. Any ideas?

 

It's either the PSOM (the part that controls the speedometer behind the dash), the VSS sensor, or its plug (over the rear differential, usually the plug corrodes or becomes loose), or maybe a generic wiring/fuse issue, those are the usual causes.

 

Expanding on a "Worst case scenario" here..

The Tone Ring, that gives the sensor the necessary pulse as an input, an be broken, or missing teeth.

The tone ring is inside the differential, stacked alongside the ring gear.

 

The tone ring would trigger a constant inaccurate movement of the needle, so I would rule that one out.

 

Again, worst case scenario, in which if teeth, etc were broken off, I could also safely assume possible damage to the sensor "Tip" that's in the differential.

 

That's a long shot since I've had a broken ring damaging a tone ring and it didn't damage the sensor, yet it could be a possibility I guess.

 

My gas guage doesn't work either, im not sure if that could be related to this issue or not.

 

Please define "the speedometer didnt work at all". Does that mean the odometer is blank too?

 

No, the gas gauge is an unrelated issue, probably caused by the float in the tank, but you can check several other things before messing with the fuel tank.