My 1991 E350 Fuse diagram is in the owners manual.
AnswerIn the owners guide. If you don't have one you can often go the library and look in their reference section. Most libraries have repair manuals there.There is a diagram in the owners manual (page 125 for fuses, page 129 for relays).Check outhttp://vehicleownersmanuals.blogspot.com/to download it for free.
http://wiki.answers.com/Q/Where_can_you_find_the_wiring_diagram_for_a_1982_ford_e3501982 ford e350
A diagram for a 1994 Ford e350 can be found in the trucks service manual. The manual can be found through most auto parts.
diagram to replace belt on E350 1994 7.3L
in the tank
your local ford dealership
My 1998 E350 takes 6.4 litres, just changing last night
electrical
Owners manual
The book on my 1998 Ford E350 says to use 5W-30.
You can find a fuse box diagram for a 1985 Ford E350 7.5 liter inside the owner's manual. You can also find it in the vehicle's Chilton repair manual.