How do I figure out what type of tranny, transfer case, and rear end fluids I need to buy? I purchased the truck used and it didn't have any manuals or any other paperwork which may indicate what I need.
The trans dipstick should have it written on there, should be Mercon V on an 04-08. The transfer case will take either Mercon(original spec) or Motorcraft Transfer Case Fluid(revised spec). The rear axle will have a tag with spec as well should be 75w140 some labeled as 75w90 were later revised to 75w140. The front diff takes 80W90 but myself and many others used 75w90 as it is a full synthetic.