Differential fluid

I have a 2011 prerunner 2wd auto lsd, I'm going to change my diff fluid, what else should I do while I'm under there

 

grease the ujoints if they have zerks

 

Inspect the inner part of your frame up near the catalytic converters for rust holes.

Drop the spare and make sure it's not rusted together. If you get a flat and this doesn't work it's going to be a very bad day.

Give everything else a once-over. Your eyeballs are good tools and they are free to use, put them to work and have fun!