I recently purchased my first Toyota, and I need a tailgate since mine is rusted in half. I have a 88 4Runner and I found a 90 thats in great shape, I know they are different gens but can I still use the 90 gate?

 

Nope, the body panels are the big difference between the 1st and 2nd gens. Mechanically, they're almost identical, but body panels are totally different

 

On the same topic:
Does anyone know if the 2nd gen tailgate fits 3rd gen?
Thanks!

 

For a 4Runner?... definitely not since the 3rd gen is a solid hatch with a window and the 2nd gen is a gate with a rolling window.