Hi just purchased a 1990 7.3 IDI diesel engine truck with 300,000 to 400,000 miles. 5 speed 4X2 transmission. Would like to change all the fluids in truck. I do not have an owners manual. Can anyone recommend what fluids this truck needs? where can I get an owners manual? thanks

 

What transmission have you got and is it 4x4 or 4x2?
You could visit fleet.ford.com and see if they have an owners manual for download.

 

5 speed 2X4

 

For the engine you will need something like Rotella or Mobil Delvac 15w40 diesel motor oil, around 10qts.
For the trans you will need Dexron3/Mercron auto trans fluid, I think around 5qts.
For the rear axle you will need something like 85w90 gear oil around 4qts. If you have a limited slip diff you will need to add a friction modifier to the axle lube.
The lube specs are the ones to use but the quantities are only approximate.

 

thank you lazy K

 

You can get a ford Service manual here :
This is for the engine

1993 7.3L Idi Turbo Diesel Service Manual Supplement - Helm Incorporated

this is for the rest:
1993 Light Truck Shop Manual - Helm Incorporated


Your other choice is Haynes or Chilton manuals but they have gaps in there info but are ok for basic info.

 

Yet ANOTHER testament to how awesome these IDIs are. 400k miles is pretty high, make sure when you change fluids to check the radiator. If you flush it, use coolant pre-charged with SCA's to stop the 7.3 from cavitation. 15w40 @ 10qts. Gear Oil in the 5 spd(80 weight i believe).

 

He has a 5spd Lazy haha. I would say that you need 85w90 for the diffs and the transmission.

 

Yes, I did see that he has the 5 speed manual but he still need ATF for it.
Sounds crazy I know but there it is.
Good advice on the coolant.

 

I've never heard of ATF in a ZF-5 Gearbox....thats just odd? I Would think the ATF is too thin for it. And yes the coolant is a must, at 400k. I would be shocked to see it hasnt cavitated or something by now if the guy didnt put SCA's in it.

 

I know a guy that runs green antifreeze in his, and it was his dad's truck new. He has always put in green. over 330,000 miles and 229,999 of those are pretty hard miles. He tows vehicles, pushes snow, and just generally drives like he on his way to a fire!

 

In his transmission?

 

Thanks to all sincerely Pontiac67

 

BTW, + 1 that the zf5 manual trans takes atf

 

here's what i tell most of the new guys i'll type it again cause im bored.

ENGINE OIL: THIS IS SOME OF THE BEST OIL YOU CAN GET AND IF ANYBODY TELLS YOU DIFFERENT THEY DON'T KNOW WHAT THEY'RE TALKING ABOUT. WE JUST WENT OVER A RECENT STUDY ON OILS AND THEIR CONTENTS AND ROTELLA DID TERRIBLE FOR THESE ENGINES. KEEP IN MIND JOHN DEERE USES THIS OIL IN 300,000+ DOLLAR TRACTORS. IF ITS GOOD ENOUGH FOR THOSE 300,000+ DOLLAR TRACTORS ITS GOOD ENOUGH FOR MY 3,000 DOLLAR TRUCK. THATS WHAT I ALWAYS SAY.....
Oil and Lubricants : Plus-50 II 15W-40 Engine Oil

COOLANT: THESE TRUCKS NEED WHAT IS CALLED SCA'S WHICH IS AN ADDITIVE USED TO PREVENT CAVITATION IN THE CYLINDER WALLS WHICH LEAD TO ENGINE FAILURE. THE JOHN DEERE COOL GARD II COOLANT COMES PRECHARGED WITH SAID SCA'S AND IS ELC (EXTENDED LIFE COOLANT) WHICH MEANS IT LAST LONGER THAN NORMAL ANTIFREEZE WHILE IT IS ELC IT IS STILL IMPORTANT TO PERIODICALLY CHECK THE LEVEL OF SCA. THIS CAN BE DONE WITH STRIPS FROM JOHN DEERE AT AROUND 4 DOLLARS A PACK. IF YOU NEED THE ADDITIVE THEY ALSO SELL IT AT AROUND 4 DOLLARS A BOTTLE.
https://jdparts.deere.com/partsmkt/d...CoolGardII.pdf

THE TRANSMISSION TAKES ATF. I USE VALVOLINE MERCRON 5 WHICH HAS WORKED GREAT FOR ME. ABSOLUTELY NO ISSUES THERE.

REAR END. I HAVE CHAMPION 80-90W WITH LIMITED SLIP ADDITIVE IN THERE AT THE MOMENT. AND ALSO HAVE NO ISSUES WITH IT PRESENTLY.