No tail lights on 98 Silverado

No brake lights. No Haz lights on rear but front work ok.
No turn signals on rear but front work at double the normal speed. Instrument panel lights are ok. Checked fuses in
instrument panel fuse block and under hood in Fuse/Relay center. Replaced all tail light bulbs
including the tail lamp circuit boards. Where else should I look?

run a wire from your batterys ground to the rear tail light. ground the tail light and see if you get it back. if that does not work your going to need a volt meter. and trace your wireing down to the plug under the spair tire. check to see if you have any power there. if not your will be chaseing it to every pinch point under the truck all the way up to the cab.

Check your trailer lights connector for corrosion, moisture, etc. I have seen this cause a good many problems in the exterior lighting wiring.

Got a bad ground somewhere back there, either from the taillight assemblies or in the trailer wiring harness.