Hi

When should I service the following? Couldn't find them in the print or online service guides

Differentials
Transfer case
Powersteering flush
Fuel injection service

Thanks
2001 4.6 Supercrew 4x4

 

I do differentials and transfer case at 100k. I have never done a power steering flush on any vehicle I've owned in over 40 years. Fuel injection service is generally not necessary unless you use crap gas - but I put a can of BG44K in my gas tank once a year.